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Colorectal Cancer - Introduction

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find some basic information about this disease and the parts of the body it may affect. This is the first page of Cancer.Net’s Guide to Colorectal Cancer. Use the menu to see other pages. Think of that menu as a roadmap for this entire guide.

About colorectal cancer

Colorectal cancer begins when healthy cells in the lining of the colon or rectum change and grow out of control, forming a mass called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread. These changes usually take years to develop. Both genetic and environmental factors can cause the changes. However, when a person has an uncommon inherited syndrome (see Risk Factors and Prevention), changes can occur in months or years.

Anatomy of the colon and rectum

The large intestine is part of the body's gastrointestinal (GI) tract or digestive system. The colon and rectum make up the large intestine, which plays an important role in the body's ability to process waste. The colon makes up the first 5 to 6 feet of the large intestine, and the rectum makes up the last 6 inches, ending at the anus.

The colon and rectum have 5 sections. The ascending colon is the portion that extends from a pouch called the cecum to the portion of the colon that is near the liver. The cecum is the beginning of the large intestine into which the small intestine empties; it’s on the right side of the abdomen. The transverse colon crosses the top of the abdomen. The descending colon takes waste down the left side. Finally, the sigmoid colon at the bottom takes waste a few more inches, down to the rectum. Waste leaves the body through the anus.

Illustration of the colon and rectum in the body.

This illustration shows the 5 sections of the colon and rectum. The ascending colon is the beginning the large intestine into which the small intestine empties; it begins on the lower right side of the abdomen and then leads up to the transverse colon. The transverse colon crosses the top of the abdomen from right to left, leading to the descending colon, which takes waste down the left side. Finally, the sigmoid colon at the bottom takes waste a few more inches, down to the rectum. A cross-section of the rectum and sigmoid colon shows where waste leaves the body, through the anus. Copyright 2004 American Society of Clinical Oncology. Robert Morreale/Visual Explanations, LLC.

About colorectal polyps

Colorectal cancer most often begins as a polyp, a noncancerous growth that may develop on the inner wall of the colon or rectum as people get older. If not treated or removed, a polyp can become a potentially life-threatening cancer. Finding and removing precancerous polyps can prevent colorectal cancer.

There are several forms of polyps. Adenomatous polyps, or adenomas, are growths that may become cancerous. They can be found with a colonoscopy (see Risk Factors and Prevention). Polyps are most easily found during a colonoscopy because they usually bulge into the colon, forming a mound on the wall of the colon that can be found by the doctor.

About 10% of colon polyps are flat and hard to find with a colonoscopy unless a dye is used to highlight them. These flat polyps have a high risk of becoming cancerous, regardless of their size.

Hyperplastic polyps may also develop in the colon and rectum. They are not considered precancerous.

Types of colorectal cancer

Colorectal cancer can begin in either the colon or the rectum. Cancer that begins in the colon is called colon cancer. Cancer that begins in the rectum is called rectal cancer.

Most colon and rectal cancers are a type of tumor called adenocarcinoma, which is cancer of the cells that line the inside tissue of the colon and rectum. This section specifically covers adenocarcinoma. Other types of cancer that occur far less often but can begin in the colon or rectum include neuroendocrine tumor of the gastrointestinal tract, gastrointestinal stromal tumor (GIST), small cell carcinoma, and lymphoma.

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If you would like more of an introduction, explore these related items. Please note that these links will take you to other sections on Cancer.Net:

The next section in this guide is Statistics. It helps explain how many people are diagnosed with colorectal cancer and general survival rates. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Statistics

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find information about the estimated number of people who will be diagnosed with colorectal cancer each year. You will also read general information on surviving the disease. Remember, survival rates depend on several factors, and no 2 people with cancer are the same. Use the menu to see other pages.

Every person is different, with different factors influencing their risk of being diagnosed with this cancer and the chance of recovery after a diagnosis. It is important to talk with your doctor about any questions you have around the general statistics provided below and what they may mean for you individually. The original sources for these statistics are provided at the bottom of this page.

How many people are diagnosed with colorectal cancer?

Colorectal cancer is the third most common cancer diagnosed in both men and women each year in the United States, excluding skin cancer.

In 2023, an estimated 153,020 adults in the United States will be diagnosed with colorectal cancer. These numbers include 106,970 new cases of colon cancer (54,420 men and 52,550 women) and 46,050 new cases of rectal cancer (27,440 men and 18,610 women). Worldwide, colorectal cancer is the third most diagnosed cancer. An estimated 1,880,725 people were diagnosed with colorectal cancer in 2020. These numbers include 1,148,515 colon cancer cases and 732,210 rectal cancer cases.

The number of colorectal cancer cases in the United States has been decreasing since the mid-1980s. During the 2000s, incidence rates dropped 3% to 4% each year. This was due to increased screening in adults aged 50 and older. From 2011 to 2019, incidence rates continued to decrease by 1% annually. However, incidence has been rising by 1% to 2% each year in younger people since the mid-1990s (see Risk Factors and Prevention). Colorectal cancer is estimated to be the fourth most commonly diagnosed cancer in the United States among men and women aged 30 to 39.

It is estimated that 52,550 deaths (28,470 men and 24,080 women) from this disease will occur in the United States in 2023. Colorectal cancer is the second leading cause of cancer death for men and women combined. It is the third leading cause of cancer death in men, as well as the third leading cause of cancer death in women. Worldwide, colorectal cancer is the second leading cause of cancer death. In 2020, an estimated 915,880 people died from colorectal cancer. This includes 576,858 people with colon cancer and 339,022 people with rectal cancer.

When colorectal cancer is found early, it can often be cured. The death rate from this type of cancer in 2020 in the United States was 57% less than what it was in 1970. This is due to improvements in treatment and increased screening, which finds colorectal changes before they turn cancerous and cancer at earlier stages. Overall, the death rate decreased around 2% each year from 2012 to 2020. However, deaths in adults under age 55 have continued to rise since the mid-2000s. Currently, there are about 1.4 million colorectal cancer survivors in the United States.

What is the survival rate for colorectal cancer?

There are different types of statistics that can help doctors evaluate a person’s chance of recovery from colorectal cancer. These are called survival statistics. A specific type of survival statistic is called the relative survival rate. It is often used to predict how having cancer may affect life expectancy. Relative survival rate looks at how likely people with colorectal cancer are to survive for a certain amount of time after their initial diagnosis or start of treatment compared to the expected survival of similar people without this cancer.

Example: Here is an example to help explain what a relative survival rate means. Please note this is only an example and not specific to this type of cancer. Let’s assume that the 5-year relative survival rate for a specific type of cancer is 90%. “Percent” means how many out of 100. Imagine there are 1,000 people without cancer, and based on their age and other characteristics, you expect 900 of the 1,000 to be alive in 5 years. Also imagine there are another 1,000 people similar in age and other characteristics as the first 1,000, but they all have the specific type of cancer that has a 5-year survival rate of 90%. This means it is expected that 810 of the people with the specific cancer (90% of 900) will be alive in 5 years.

It is important to remember that statistics on the survival rates for people with colorectal cancer are only an estimate. They cannot tell an individual person if cancer will or will not shorten their life. Instead, these statistics describe trends in groups of people previously diagnosed with the same disease, including specific stages of the disease.

The 5-year relative survival rate for colorectal cancer in the United States is 65%.

The survival rates for colorectal cancer vary based on several factors. These include the stage of cancer, a person’s age and general health, and how well the treatment plan works.

The 5-year relative survival rate for localized stage colorectal cancer is 91%. About 37% of patients are diagnosed at this early stage. If the cancer has spread to surrounding tissues or organs and/or the regional lymph nodes, the 5-year relative survival rate is 73%. About 36% of patients are diagnosed at this regional stage. If the cancer has spread to distant parts of the body, the 5-year relative survival rate is 14%. About 22% of patients are diagnosed at this late stage. However, for patients who have just 1 or a few tumors that have spread from the colon or rectum to the lung or liver, surgical removal of these tumors can sometimes eliminate the cancer, which greatly improves the 5-year relative survival rate for these patients.

Survival rates are also available for colon cancer and rectal cancer separately. For colon cancer, the overall 5-year relative survival rate for people is 63%. If the cancer is diagnosed at a localized stage, the survival rate is 91%. If the cancer has spread to surrounding tissues or organs and/or the regional lymph nodes, the 5-year relative survival rate is 72%. If colon cancer has spread to distant parts of the body, the 5-year relative survival rate is 13%.

For rectal cancer, the overall 5-year relative survival rate for people is 68%. If the cancer is diagnosed at a localized stage, the survival rate is 90%. If the cancer has spread to surrounding tissues or organs and/or the regional lymph nodes, the 5-year relative survival rate is 74%. If the cancer has spread to distant parts of the body, the 5-year relative survival rate is 17%.

Experts measure relative survival rate statistics for colorectal cancer every 5 years. This means the estimate may not reflect the results of advancements in how colorectal cancer is diagnosed or treated from the last 5 years. Talk with your doctor if you have any questions about this information. Learn more about understanding statistics.

Statistics adapted from the American Cancer Society's (ACS) publications, Cancer Facts & Figures 2023 and Cancer Facts & Figures 2020: Special Section – Cancer in Adolescents and Young Adults; the International Agency for Research on Cancer website; and the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program. (All sources accessed February 2023.)

The next section in this guide is Medical Illustrations. It offers drawings of body parts often affected by colorectal cancer. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Medical Illustrations

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find a drawing of the main body parts affected by colorectal cancer. Use the menu to see other pages.

Illustration of the colon and rectum in the body.

This illustration shows the 5 sections of the colon and rectum. The ascending colon is the beginning the large intestine into which the small intestine empties; it begins on the lower right side of the abdomen and then leads up to the transverse colon. The transverse colon crosses the top of the abdomen from right to left, leading to the descending colon, which takes waste down the left side. Finally, the sigmoid colon at the bottom takes waste a few more inches, down to the rectum. A cross-section of the rectum and sigmoid colon shows where waste leaves the body, through the anus. Copyright 2004 American Society of Clinical Oncology. Robert Morreale/Visual Explanations, LLC.

Copyright 2021 American Society of Clinical Oncology. Robert Morreale.

The next section in this guide is Risk Factors and Prevention. It describes the factors that may increase the chance of developing colorectal cancer. Use the menu to choose a different section to read in this guide. 

Colorectal Cancer - Risk Factors and Prevention

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find out more about the factors that increase the chance of developing colorectal cancer. Use the menu to see other pages.

What are the risk factors for colorectal cancer?

A risk factor is anything that increases a person’s chance of developing cancer. Although risk factors often influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. Knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices.

A person with an average risk of colorectal cancer has about a 5% chance of developing colorectal cancer overall. Generally, most colorectal cancers (about 95%) are considered sporadic, meaning the genetic changes develop by chance after a person is born, so there is no risk of passing these genetic changes on to one’s children. Inherited colorectal cancers are less common (about 5% to 10%) and occur when gene mutations, or changes, are passed within a family from 1 generation to the next (see below). Up to 30% of colorectal cancers are diagnosed in people with a family history of colon or rectal cancer but without a known inherited condition (see below). Often the cause of colorectal cancer is not known. However, the following factors may raise a person’s risk of developing colorectal cancer:

  • Age. The risk of colorectal cancer increases as people get older. Colorectal cancer can occur in young adults and teenagers, but the majority of colorectal cancers occur in people older than 50. For colon cancer, the average age at the time of diagnosis for men is 66 and for women is 69. For rectal cancer, it is age 62 for men and 63 for women. Adults 65 and older who are diagnosed with colorectal cancer face unique challenges, specifically with regard to cancer treatment. Learn more about aging and cancer.

    It is important to note that while colorectal cancer is still diagnosed most commonly in older adults, the incidence rate for colorectal cancer declined by about 3.6% per year in adults 55 and older, based on the latest statistics. Meanwhile, the incidence rate increased by 2% per year in adults younger than 55. The increase is due in large part to rising numbers of rectal cancer. About 20% of all colorectal diagnoses are in people under age 55. The reason for this rise in younger adults is not well known and is an active area of research.

  • Race. Black people have the highest rates of sporadic, or non-hereditary, colorectal cancer in the United States. Colorectal cancer is also a leading cause of cancer-related death among Black people. Black women are more likely to die from colorectal cancer than women from any other racial group, and Black men are even more likely to die from colorectal cancer than Black women. The reasons for these differences are unclear.

  • Sex. Men have a slightly higher risk of developing colorectal cancer than women.

  • Family history of colorectal cancer. Colorectal cancer may run in the family if first-degree relatives (parents, brothers, sisters, children) or many other family members (grandparents, aunts, uncles, nieces, nephews, grandchildren, cousins) have had colorectal cancer. This is especially true when family members are diagnosed with colorectal cancer before age 60. If a person has a family history of colorectal cancer, their risk of developing the disease is nearly double. The risk further increases if other close relatives have also developed colorectal cancer or if a first-degree relative was diagnosed at a younger age.

    About 5% to 10% of cases of colorectal cancer are associated with inherited genetic mutations that increase the risk of cancer and affect the way that the cancer is treated. This is why your doctor may recommend evaluation for inherited mutations if you have been diagnosed with colorectal cancer. Evaluation may include review of personal and family histories of cancer and molecular testing of tumor tissue.

    It is important to talk to your family members about your family’s history of colorectal cancer. If you think you may have a family history of colorectal cancer, talk with a genetic counselor before you have any genetic testing. Only genetic testing can find out if you have a genetic mutation, and genetic counselors are trained to explain the risks and benefits of genetic testing.

  • Rare inherited conditions.Members of families with certain uncommon inherited conditions have a higher risk of colorectal cancer, as well as other types of cancer. These include:

  • Inflammatory bowel disease (IBD). People with IBD, such as ulcerative colitis or Crohn’s disease, may develop chronic inflammation of the large intestine. This increases the risk of colorectal cancer. IBD is not the same as irritable bowel syndrome (IBS). IBS does not increase your risk of colorectal cancer.

  • Adenomatous polyps (adenomas). Polyps are not cancer, but some types of polyps called adenomas can develop into colorectal cancer over time. Polyps can often be completely removed using a tool during a colonoscopy, a test in which a doctor looks into the colon using a lighted tube after the patient has been sedated. Polyp removal can prevent colorectal cancer. People who have had adenomas have a greater risk of additional polyps and of colorectal cancer, and they should have follow-up screening tests regularly (see Screening).

  • Personal history of certain types of cancer. People with a personal history of colorectal cancer previously or a diagnosis of ovarian cancer or uterine cancer are more likely to develop colorectal cancer.

  • Physical inactivity and obesity. An inactive lifestyle, meaning no regular exercise and a lot of sitting, and being overweight or obese may increase a person's risk of colorectal cancer.

  • Food/diet. Current research consistently links eating more red meat and processed meat to a higher risk of the disease. Other dietary factors have also been studied to see if they affect the risk of developing colorectal cancer, but the data are less consistent on which diets or foods change a person's risk of colorectal cancer.

  • Smoking. Recent studies have shown that people who smoke are more likely to die from colorectal cancer than those who do not smoke. Learn more about quitting tobacco use.

  • Diabetes. Studies have shown that people with type 2 diabetes have an increased risk for colorectal cancer.

Are there ways to prevent colorectal cancer?

Different factors cause different types of cancer. Researchers continue to look into what factors cause colorectal cancer, including ways to prevent it. Although there is no proven way to completely prevent colorectal cancer, you may be able to lower your risk. Talk with your health care team for more information about your personal risk of colorectal cancer.

As explained above, polyp removal during a colonoscopy (see Screening) can help prevent colorectal cancer. This procedure allows the doctor to look inside the large intestine to look for and remove polyps that could turn into cancer.

The following may also lower a person’s risk of colorectal cancer:

  • Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs). Some studies suggest that aspirin and other NSAIDs may reduce the development of polyps in people with a history of colorectal cancer or polyps. However, regular use of aspirin or NSAIDs may cause major side effects, including bleeding of the stomach lining and blood clots, leading to stroke or heart attack. Taking aspirin or other NSAIDs is not a substitute for having regular colorectal cancer screenings. People should talk with their doctor about the risks and benefits of taking aspirin on a regular basis.

  • Managing your body weight. There is evidence that links higher body weight with a higher risk of developing colorectal cancer. Eating well is one of the best ways to improve your health and lower your cancer risk. This can help you maintain your body weight or lose weight if necessary.

  • Being physically active. Being physically active can lower your risk of colorectal cancer. The American Cancer Society recommends that adults should get 150 to 300 minutes of moderate-intensity physical activity per week or 75 to 150 minutes of vigorous-intensity physical activity, or a combination of these. Getting to 300 minutes or more is best. Children and teens should get at least 1 hour of moderate- or vigorous-intensity activity every day. Try to reduce the amount of sedentary behavior in your daily life, such as sitting, lying down, and watching television and other screen-based entertainment.

  • Managing your food choices. Eating patterns that are rich in fruits and vegetables and low in red meat may help reduce the risk of colorectal cancer. Some studies have also found that people who take calcium and vitamin D supplements have a lower risk of colorectal cancer.

Learn more about cancer prevention and healthy living.

The next section in this guide is Screening. It explains how tests may find colorectal cancer before signs or symptoms appear. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Screening

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find out more about screening for colorectal cancer. You will also learn the risks and benefits of screening. Use the menu to see other pages.

Screening is used to look for cancer before you have any symptoms or signs. Scientists have developed, and continue to develop, tests that can be used to screen a person for specific types of cancer before signs or symptoms appear. The overall goals of cancer screening are to:

  • Lower the number of people who die from the disease, or eliminate deaths from cancer altogether

  • Lower the number of people who develop the disease

  • Identify people who may need more frequent screening or a different type of screening because they have a higher risk of developing cancer due to genetic mutations, hereditary syndromes, or family history

Learn more about the basics of cancer screening.

How are people screened for colorectal cancer?

Colorectal cancer can often be prevented through regular screening, which can find polyps before they become cancerous. Talk with your doctor about when screening should begin based on your age and family history of the disease. See more information below for screening recommendations.

Because colorectal cancer usually does not cause symptoms until the disease is advanced, it is important for people to talk with their doctor about the pros and cons of each screening test and how often each test should be given. Under the guidelines below, people should begin colorectal cancer screening earlier and/or undergo screening more often if they have any of the following risk factors for colorectal cancer:

  • A personal history of colorectal cancer or adenomatous polyps.

  • A strong family history of colorectal cancer or polyps, such as cancer or polyps in a first-degree relative younger than 60 or in 2 first-degree relatives of any age. A first-degree relative is defined as a parent, sibling, or child.

  • A personal history of chronic inflammatory bowel disease (IBD).

  • A family history of any hereditary colorectal cancer syndrome, such as familial adenomatous polyposis (FAP), Lynch syndrome, or other syndromes (see Risk Factors and Prevention).

The tests used to screen for colorectal cancer are described below.

  • Colonoscopy. A colonoscopy allows the doctor to look inside the entire rectum and colon while a patient is sedated. A flexible, lighted tube called a colonoscope is inserted into the rectum and the entire colon to look for polyps or cancer. During this procedure, a doctor can remove polyps or other tissue for examination (see “Biopsy” in the Diagnosis section). The removal of polyps can also prevent colorectal cancer.

  • Computed tomography (CT or CAT) colonography. CT colonography, sometimes called virtual colonoscopy, is a screening method being studied in some centers. It requires interpretation by a skilled radiologist to provide the best results. A radiologist is a doctor who specializes in obtaining and interpreting medical images. CT colonography may be an alternative for people who cannot have a standard colonoscopy due to the risk of anesthesia, which is medication to block the awareness of pain, or if a person has a blockage in the colon that prevents a full examination.

  • Sigmoidoscopy. A sigmoidoscopy uses a flexible, lighted tube that is inserted into the rectum and lower colon to check for polyps, cancer, and other abnormalities. During this procedure, a doctor can remove polyps or other tissue for later examination. The doctor cannot check the upper part of the colon, the ascending and transverse colon, with this test. This screening test can be used to remove polyps, which can also prevent colorectal cancer, but if polyps or cancer are found using this test, a colonoscopy to view the entire colon is recommended.

  • Fecal occult blood test (FOBT) and fecal immunochemical test (FIT). A fecal occult blood test is used to find blood in the feces, or stool, which can be a sign of polyps or cancer. A positive test, meaning that blood is found in the feces, can be from causes other than a colon polyp or cancer, including bleeding in the stomach or upper gastrointestinal (GI) tract and even eating rare meat or other foods. There are 2 types of tests: guaiac (FOBT) and immunochemical (FIT). Polyps and cancers do not bleed continually, so FOBT must be done on several stool samples each year and should be repeated every year. Even then, this screening test provides a fairly small reduction in deaths from colorectal cancer, around 30% if done yearly and 18% if done every other year.

  • Stool DNA tests. This test analyzes the DNA from a person’s stool sample to look for cancer. It uses changes in the DNA that occur in polyps and cancers to find out if a colonoscopy should be done.

  • Double contrast barium enema (DCBE). For patients who cannot have a colonoscopy, an enema containing barium is given, which helps make the colon and rectum stand out on x-rays. A series of x-rays is then taken of the colon and rectum. In general, most doctors would recommend other screening tests because a barium enema is less likely to detect precancerous polyps than a colonoscopy, sigmoidoscopy, or CT colonography.

Colorectal cancer screening recommendations

Different organizations have made different recommendations for colorectal cancer screening, described below. Talk with your doctor about the best test(s) and time between tests based on your health history and personal colorectal cancer risk.

The American Society of Clinical Oncology (ASCO) developed guidelines in 2019 for colorectal cancer screening to help prevent cancer for people with an average risk. Beginning at age 50, both men and women with an average risk of colorectal cancer should follow 1 of these testing schedules. People with an average risk do not have a family history of the disease, an inherited syndrome such as Lynch syndrome, or IBD, and they have not been diagnosed with colorectal cancer in the past.

The following tests detect both polyps and cancer:

  • Flexible sigmoidoscopy every 5 years, or every 10 years with FIT or FOBT every year

  • Colonoscopy, every 10 years

  • DCBE, every 5 years

  • CT colonography, as often as your doctor recommends

These tests primarily detect cancer:

  • Guaiac-based FOBT, every year

  • FIT, every year

  • Stool DNA test, as often as your doctor recommends

Access to certain screening services may be limited in rural and other underserved areas. Talk with your health care team about your options nearby, and learn more about ASCO's recommendations for preventing colorectal cancer.

The U.S. Preventive Services Task Force (USPSTF) also has guidelines for colorectal cancer screening, which do not recommend any specific screening method. Instead, USPSTF simply recommends that people between ages 45 and 75 should receive regular screening.

According to the USPSTF, adults between ages 76 and 85 should talk with their doctor to see if screening is right for them. However, people who have a history of polyps or colorectal cancer have a higher risk of the disease, and screening may still be recommended at an older age. Learn more about treatment decisions in older patients.

Due to the rising incidence of colorectal cancer in younger people, the American Cancer Society recommends that people at average risk of colorectal cancer start regular screening at age 45.

It is important to note that, regardless of which screening test and schedule used, any test that indicates an abnormality should be followed up with a colonoscopy.

The next section in this guide is Symptoms and Signs. It explains what changes or medical problems colorectal cancer can cause. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Symptoms and Signs

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find out more about the changes and medical problems that can be a sign of colorectal cancer. Use the menu to see other pages.

What are the symptoms and signs of colorectal cancer?

It is important to remember that the symptoms and signs of colorectal cancer listed in this section are the same as those of extremely common conditions that are not cancer, such as hemorrhoids and irritable bowel syndrome (IBS). When cancer is suspected, these symptoms usually have begun recently, are severe and long lasting, and change over time. By being alert to the symptoms or signs of colorectal cancer, it may be possible to detect the disease early, when it is most likely to be treated successfully. However, many people with colorectal cancer do not have any symptoms or signs until the disease is advanced, so people need to be screened regularly.

People with colorectal cancer may experience one or more of the following symptoms or signs. Symptoms are changes that you can feel in your body. Signs are changes in something measured, like taking your blood pressure or doing a lab test. Together, symptoms and signs can help describe a medical problem. As mentioned above, it is also possible that the symptoms and signs described below may be caused by a medical condition that is not cancer, especially for the general symptoms of abdominal discomfort, bloating, and irregular bowel movements.

  • A change in bowel habits

  • Diarrhea, constipation, or feeling that the bowel does not empty completely

  • Bright red or very dark blood in the stool

  • Stools that look narrower or thinner than normal

  • Discomfort in the abdomen, including frequent gas pains, bloating, fullness, and cramps

  • Weight loss with no known explanation

  • Constant tiredness or fatigue

  • Unexplained iron-deficiency anemia, which is a low number of red blood cells

Talk with your doctor if any of these symptoms last for several weeks or become more severe. If you are concerned about any changes you experience, please talk with your doctor and ask to schedule a colonoscopy.

Because colorectal cancer can occur in people younger than the recommended screening age and in older people between screenings, anyone at any age who experiences these symptoms should visit a doctor to find out if they should have a colonoscopy.

Your doctor will try to understand what is causing your symptom(s). They may do an exam and order tests to understand the cause of the problem, which is called a diagnosis.

If cancer is diagnosed, relieving symptoms remains an important part of cancer care and treatment. Managing symptoms may also be called "palliative and supportive care,” which is not the same as hospice care given at the end of life. This type of care focuses on managing symptoms and supporting people who face serious illnesses, such as cancer. You can receive palliative and supportive care at any time during cancer treatment. Learn more in this guide’s section on Coping with Treatment.

Be sure to talk with your health care team about the symptoms you experience, including any new symptoms or a change in symptoms.

The next section in this guide is Diagnosis. It explains what tests may be needed to learn more about the cause of the symptoms. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Diagnosis

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, cancer. They also do tests to learn if cancer has spread to another part of the body from where it started. If the cancer has spread, it is called metastasis. Doctors may also do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know whether an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

How colorectal cancer is diagnosed

There are different tests used for diagnosing colorectal cancer. Not all tests described here will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and general health

  • Your medical and family history

  • The results of earlier medical tests

In addition to a physical examination, the following tests may be used to diagnose colorectal cancer.

  • Colonoscopy. As described in Screening, a colonoscopy allows the doctor to look inside the entire rectum and colon while a patient is sedated. This test is usually done by a gastroenterologist or colorectal surgeon. If colorectal cancer is found, a complete diagnosis that accurately describes the location and spread of the cancer may not be possible until the tumor is surgically removed.

  • Biopsy. A biopsy is the only way to make a definite diagnosis, even if other tests can suggest that cancer is present. During a biopsy, a small amount of tissue is removed for examination under a microscope. A pathologist analyzes the sample(s). A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease. A biopsy may be performed during a colonoscopy, or it may be done on any tissue that is removed during surgery. Sometimes, a CT scan or ultrasound (see below) is used to help perform a needle biopsy. A needle biopsy removes tissue through the skin with a needle that is guided into the tumor.

  • Biomarker testing of the tumor. Your doctor may recommend running laboratory tests on a tumor sample to identify specific genes, proteins, and other factors unique to the tumor. This may also be called molecular testing or next generation sequencing of the tumor. Results of these tests may help determine your treatment options.

    All colorectal cancers should be tested for problems in mismatch repair proteins, called a mismatch repair deficiency (dMMR). There are 2 reasons for this testing. First, it is a way to look for Lynch syndrome (see Risk Factors and Prevention). Second, the results will be used to find out if immunotherapy should be considered in the treatment of metastatic disease. This testing can either be done using special staining of the tissue taken from a biopsy or surgery or by doing analyses that look for changes called microsatellite instability (MSI).

    If you have metastatic or recurrent colorectal cancer, a sample of tissue from the area where it spread or recurred is preferred for testing, if available.

  • Blood tests. Because colorectal cancer often bleeds into the large intestine or rectum, people with the disease may become anemic. A test of the number of red cells in the blood, which is part of a complete blood count (CBC), can indicate that bleeding may be occurring.

    Another blood test detects the levels of a protein called carcinoembryonic antigen (CEA). High levels of CEA may indicate that a cancer has spread to other parts of the body. CEA is not a perfect test for colorectal cancer because levels are high for only about 60% of people with colorectal cancer that has spread from the colon to other organs. In addition, other medical conditions can cause CEA to increase. A CEA test is most often used to monitor colorectal cancer for people who are already receiving treatment. It is not useful as a screening test. Learn more about tumor markers for cancer.

  • Computed tomography (CT or CAT) scan. A CT scan takes pictures of the inside of the body using x-rays taken from different angles. A computer combines these pictures into a detailed, 3-dimensional image that shows any abnormalities or tumors. A CT scan can be used to measure the tumor’s size. Sometimes a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a patient’s vein or given as a pill or liquid to swallow. In a person with colorectal cancer, a CT scan can check for the spread of cancer to the lungs, liver, and other organs. It is often done before surgery (see Types of Treatment).

  • Magnetic resonance imaging (MRI). An MRI produces detailed images of the inside of the body using magnetic fields, not x-rays. MRI can be used to measure the tumor’s size. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye can be injected into a patient’s vein or given as a pill or liquid to swallow. MRI is the best imaging test to find where rectal cancer has grown.

  • Ultrasound. An ultrasound creates a picture of the internal organs using sound waves to find out if cancer has spread. Endorectal ultrasound is commonly used to find out how deeply rectal cancer has grown and can be used to help plan treatment. However, this test cannot accurately detect cancer that has spread to nearby lymph nodes or beyond the pelvis. Ultrasound can also be used to view the liver, although CT scans or MRIs (see above) are better for finding tumors in the liver.

  • Chest x-ray. An x-ray creates a picture of the structures inside of the body using a small amount of radiation. An x-ray of the chest can help doctors find out if the cancer has spread to the lungs. However, CT scans of the chest are better for finding tumors in the lungs or chest.

  • Positron emission tomography (PET) or PET-CT scan. A PET scan creates pictures of organs and tissues inside the body. A PET scan is usually combined with a CT scan (see above), called a PET-CT scan. However, you may hear your doctor refer to this procedure just as a PET scan. A small amount of a radioactive sugar substance is injected into the patient’s body. This sugar substance is taken up by cells that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. However, the amount of radiation in the substance is too low to be harmful. A scanner then detects this substance to produce images of the inside of the body. PET scans are not regularly used for all people with colorectal cancer, but there are specific situations when your doctor may recommend one.

After diagnostic tests are done, your doctor will review the results with you. If the diagnosis is cancer, these results also help the doctor describe the cancer. This is called staging.

The next section in this guide is Stages. It explains the system doctors use to describe the extent of the disease. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Stages

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will learn about how doctors describe a cancer’s growth or spread. This is called the stage. Use the menu to see other pages.

READ MORE BELOW:

What is cancer staging?

Staging is a way of describing where the cancer is located, if or where it has spread, and whether it is affecting other parts of the body.

Doctors use diagnostic tests to find out the cancer's stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor recommend the best kind of treatment, and it can help predict a patient's prognosis, which is the chance of recovery. There are different stage descriptions for different types of cancer.

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TNM staging system

One tool that doctors use to describe the stage is the TNM system. Doctors use the results from diagnostic tests and scans to answer these questions:

  • Tumor (T): Has the tumor grown into the wall of the colon or rectum? How many layers?

  • Node (N): Has the tumor spread to the lymph nodes? If so, where and how many?

  • Metastasis (M): Has the cancer spread to other parts of the body? If so, where and how much?

The results are combined to determine the stage of cancer for each person.

There are 5 stages: stage 0 (zero) and stages I through IV (1 through 4). The stage provides a common way of describing the cancer, so doctors can work together to plan the best treatments.

Here are more details on each part of the TNM system for colorectal cancer:

Tumor (T)

Using the TNM system, the "T" plus a letter or number (0 to 4) is used to describe how deeply the primary tumor has grown into the bowel lining. Stage may also be divided into smaller groups that help describe the tumor in even more detail. Specific tumor information is listed below.

TX: The primary tumor cannot be evaluated.

T0 (T zero): There is no evidence of cancer in the colon or rectum.

Tis: Refers to carcinoma in situ (also called cancer in situ). Cancer cells are found only in the epithelium or lamina propria, which are the top layers lining the inside of the colon or rectum.

T1: The tumor has grown into the submucosa, which is the layer of tissue underneath the mucosa or lining of the colon.

T2: The tumor has grown into the muscularis propria, a deeper, thick layer of muscle that contracts to force along the contents of the intestines.

T3: The tumor has grown through the muscularis propria and into the subserosa, which is a thin layer of connective tissue beneath the outer layer of some parts of the large intestine, or it has grown into tissues surrounding the colon or rectum.

T4a: The tumor has grown into the surface of the visceral peritoneum, which means it has grown through all layers of the colon.

T4b: The tumor has grown into or has attached to other organs or structures.

Node (N)

The "N" in the TNM system stands for lymph nodes. The lymph nodes are small, bean-shaped organs located throughout the body. Lymph nodes help the body fight infections as part of the immune system. Lymph nodes near the colon and rectum are called regional lymph nodes. All others are distant lymph nodes that are found in other parts of the body.

NX: The regional lymph nodes cannot be evaluated.

N0 (N zero): There is no spread to regional lymph nodes.

N1a: There are tumor cells found in 1 regional lymph node.

N1b: There are tumor cells found in 2 or 3 regional lymph nodes.

N1c: There are nodules made up of tumor cells found in the structures near the colon that do not appear to be lymph nodes.

N2a: There are tumor cells found in 4 to 6 regional lymph nodes.

N2b: There are tumor cells found in 7 or more regional lymph nodes.

Metastasis (M)

The "M" in the TNM system describes cancer that has spread to other parts of the body, such as the liver or lungs. This is called metastasis.

M0 (M zero): The disease has not spread to a distant part of the body.

M1a: The cancer has spread to 1 other part of the body beyond the colon or rectum.

M1b: The cancer has spread to more than 1 part of the body other than the colon or rectum.

M1c: The cancer has spread to the peritoneal surface.

Grade (G)

Doctors also describe colorectal cancer by its grade (G). The grade describes how much cancer cells look like healthy cells when viewed under a microscope.

The doctor compares the cancerous tissue with healthy tissue. Healthy tissue usually contains many different types of cells grouped together. If the cancer looks similar to healthy tissue and has different cell groupings, it is called "differentiated" or a "low-grade tumor." If the cancerous tissue looks very different from healthy tissue, it is called "poorly differentiated" or a "high-grade tumor." The cancer’s grade may help the doctor predict how quickly the cancer will spread. In general, the lower the tumor’s grade, the better the prognosis.

GX: The tumor grade cannot be identified.

G1: The cells are more like healthy cells, called well differentiated.

G2: The cells are somewhat like healthy cells, called moderately differentiated.

G3: The cells look less like healthy cells, called poorly differentiated.

G4: The cells barely look like healthy cells, called undifferentiated.

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Stage groups for colorectal cancer

Doctors combine the T, N, and M information (see above) to say what stage the cancer is.

Stage 0: This is called cancer in situ. The cancer cells are only in the mucosa, or the inner lining, of the colon or rectum.

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Stage I: The cancer has grown through the mucosa and has invaded the muscular layer of the colon or rectum. It has not spread into nearby tissue or lymph nodes (T1 or T2, N0, M0).

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Stage IIA: The cancer has grown through the wall of the colon or rectum but has not spread to nearby tissue or to the nearby lymph nodes (T3, N0, M0).

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Stage IIB: The cancer has grown through the layers of the muscle to the lining of the abdomen, called the visceral peritoneum. It has not spread to the nearby lymph nodes or elsewhere (T4a, N0, M0).

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Stage IIC: The tumor has spread through the wall of the colon or rectum and has grown into nearby structures. It has not spread to the nearby lymph nodes or elsewhere (T4b, N0, M0).

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Stage IIIA: The cancer has grown through the inner lining or into the muscle layers of the intestine. It has spread to 1 to 3 lymph nodes or to a nodule of tumor cells in tissues around the colon or rectum that do not appear to be lymph nodes but has not spread to other parts of the body (T1 or T2, N1 or N1c, M0; or T1, N2a, M0).

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Stage IIIB: The cancer has grown through the bowel wall or to surrounding organs and into 1 to 3 lymph nodes or to a nodule of tumor in tissues around the colon or rectum that do not appear to be lymph nodes. It has not spread to other parts of the body (T3 or T4a, N1 or N1c, M0; T2 or T3, N2a, M0; or T1 or T2, N2b, M0).

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Stage IIIC: The cancer of the colon, regardless of how deep it has grown, has spread to 4 or more lymph nodes but not to other distant parts of the body (T4a, N2a, M0; T3 or T4a, N2b, M0; or T4b, N1 or N2, M0).

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Stage IVA: The cancer has spread to a single distant part of the body, such as the liver or lungs (any T, any N, M1a).

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Stage IVB: The cancer has spread to more than 1 part of the body (any T, any N, M1b).

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Stage IVC: The cancer has spread to the peritoneum. It may also have spread to other sites or organs (any T, any N, M1c).

Recurrent: Recurrent cancer is cancer that has come back after treatment. The disease may be found in the colon, rectum, or in another part of the body. If the cancer does return, there will be another round of tests to learn about the extent of the recurrence. These tests and scans are often similar to those done at the time of the original diagnosis.

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Used with permission of the American College of Surgeons, Chicago, Illinois. The original and primary source for this information is the AJCC Cancer Staging Manual, Eighth Edition (2017), published by Springer International Publishing.

Information about the cancer’s stage will help the doctor recommend a specific treatment plan. The next section in this guide is Types of Treatment. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Types of Treatment

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will learn about the different types of treatments doctors use for people with colorectal cancer. Use the menu to see other pages.

This section explains the types of treatments, also known as therapies, that are the standard of care for colorectal cancer. “Standard of care” means the best treatments known. Information in this section is based on medical standards of care for colorectal cancer in the United States. Treatment options can vary from one place to another.

When making treatment plan decisions, you are encouraged to discuss with your doctor whether clinical trials offer additional options to consider. A clinical trial is a research study that tests a new approach to treatment. Doctors learn through clinical trials whether a new treatment is safe, effective, and possibly better than the standard treatment. Clinical trials can test a new drug, a new combination of standard treatments, or new doses of standard drugs or other treatments. Clinical trials are an option for all stages of cancer. Your doctor can help you consider all your treatment options. Learn more about clinical trials in the About Clinical Trials and Latest Research sections of this guide.

How colorectal cancer is treated

In cancer care, different types of doctors who specialize in cancer, called oncologists, often work together to create a patient’s overall treatment plan that usually includes or combines different types of treatments. This is called a multidisciplinary team. For colorectal cancer, this generally includes a surgeon, medical oncologist, radiation oncologist, and a gastroenterologist. A gastroenterologist is a doctor who specializes in the function and disorders of the gastrointestinal tract. Cancer care teams include other health care professionals, such as physician assistants, nurse practitioners, oncology nurses, social workers, pharmacists, counselors, genetic counselors, dietitians, physical therapists, occupational therapists, and others. Learn more about the clinicians who provide cancer care.

Treatment options and recommendations depend on several factors, including the type and stage of cancer, possible side effects, and the patient’s preferences and overall health. Take time to learn about all of your treatment options and be sure to ask questions about things that are unclear. Talk with your doctor about the goals of each treatment and what you can expect while receiving the treatment. These types of conversations are called “shared decision-making.” Shared decision-making is when you and your doctors work together to choose treatments that fit the goals of your care. Shared decision-making is important for colorectal cancer because there are different treatment options. Learn more about making treatment decisions.

Studies have shown that these various treatment approaches provide similar benefits regardless of the patient’s age. However, adults age 65 and older may have unique treatment challenges. Learn more about the specific effects of surgery, chemotherapy, and radiation therapy on adults 65 and older. In order to tailor the treatment to each patient, all treatment decisions should consider such factors as:

  • The patient’s other medical conditions

  • The patient’s overall health

  • Potential side effects of the treatment plan

  • Other medications that the patient already takes

  • The patient’s nutritional status and social support

The common types of treatments used for colorectal cancer are described below, followed by a brief outline of treatment options listed by stage. Your care plan may also include treatment for symptoms and side effects, an important part of cancer care.

READ MORE BELOW:

Surgery

Surgery is the removal of the tumor and some surrounding healthy tissue during an operation. It is often called surgical resection. This is the most common treatment for colorectal cancer. Part of the healthy colon or rectum and nearby lymph nodes will also be removed.

While both general surgeons and specialists may perform colorectal surgery, many people talk with specialists who have additional training and experience in colorectal surgery. A surgical oncologist is a doctor who specializes in treating cancer using surgery. A colorectal surgeon is a doctor who has received additional training to treat diseases of the colon, rectum, and anus. Colorectal surgeons used to be called proctologists.

In addition to surgical resection, surgical options for colorectal cancer include:

  • Laparoscopic surgery. Some patients may be able to have laparoscopic colorectal cancer surgery. With this technique, several viewing scopes are passed into the abdomen while a patient is under anesthesia. Anesthesia is medicine that blocks the awareness of pain. The incisions are smaller, and the recovery time is often shorter than with standard colon surgery. Laparoscopic surgery is as effective as conventional colon surgery in removing the cancer. Surgeons who perform laparoscopic surgery have been specially trained in that technique.

  • Robotic surgery. In this procedure, the surgeon controls robotic surgical tools to remove the tumor and, if needed, lymph nodes through small incisions. The technology provides the surgeon with a magnified view of the surgical area and precise control of small surgical tools. This means that the surgery can be performed using fewer and smaller incisions, or cuts, in the body, which may lower the risk of side effects from the surgery. Robotic surgery may also be helpful when the surgical area, such as the rectum, is harder to operate in using larger surgical tools held in a surgeon’s hand.

  • Colostomy for rectal cancer. Less often, a person with rectal cancer may need to have a colostomy. This is a surgical opening, or stoma, through which the colon is connected to the abdominal surface to provide a pathway for waste to exit the body. This waste is collected in a pouch worn by the patient. Sometimes, the colostomy is only temporary to allow the rectum to heal, but it may be permanent. With modern surgical techniques and the use of radiation therapy and chemotherapy before surgery when needed, most people who receive treatment for rectal cancer do not need a permanent colostomy. Learn more about colostomies.

  • Radiofrequency ablation (RFA) or cryoablation. Some patients may have surgery on the liver or lungs to remove colorectal cancer that has spread to those organs. Optional treatments include using energy in the form of radiofrequency waves to heat the tumors, called RFA, or to freeze the tumor, called cryoablation. Not all liver or lung tumors can be treated with these approaches. RFA can be done through the skin or during surgery. While this can help avoid removing parts of the liver and lung tissue that might be removed in a regular surgery, there is also a chance that parts of tumor will be left behind.

Side effects of surgery

Before surgery, talk with your health care team about the possible side effects from the specific surgery you will have and ask how side effects can be prevented or relieved. In general, the side effects of surgery include pain and tenderness in the area of the operation. The operation may also cause constipation or diarrhea, which usually goes away after a while. People who have a colostomy may have irritation around the stoma. If you need to have a colostomy, the doctor, nurse, or an enterostomal therapist, who is a specialist in colostomy management, can teach you how to clean the area and prevent infection.

Many people need to retrain their bowel after surgery. This may take some time and assistance. You should talk with your doctor if you do not regain good control of bowel function.

Learn more about the basics of cancer surgery.

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Radiation therapy

Radiation therapy is the use of high-energy x-rays to destroy cancer cells. It is commonly used for treating rectal cancer because this kind of tumor tends to recur near where it originally started. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. A radiation therapy regimen, or schedule, usually consists of a specific number of treatments given over a set period of time.

External-beam radiation therapy. External-beam radiation therapy uses a machine to deliver x-rays to where the cancer is located. Radiation treatment is usually given 5 days a week for several weeks. It may be given in the doctor's office or at the hospital.

Stereotactic radiation therapy. Stereotactic radiation therapy is a type of external-beam radiation therapy that may be used if colorectal cancer has spread to the liver or lungs. This type of radiation therapy delivers a large, precise radiation dose to a small area. This technique can help save parts of the liver and lung tissue that might otherwise have to be removed during surgery. However, not all cancers that have spread to the liver or lungs can be treated in this way.

Other types of radiation therapy. For some people, specialized radiation therapy techniques, such as intraoperative radiation therapy or brachytherapy, may help get rid of small areas of cancer that can not be removed with surgery.

  • Intraoperative radiation therapy. Intraoperative radiation therapy uses a single, high dose of radiation therapy given during surgery.

  • Brachytherapy. Brachytherapy is the use of radioactive "seeds" placed inside the body.

  • Yttrium-90. In this form of radiation therapy, tiny amounts of a radioactive substance called yttrium-90 are injected into the liver to treat colorectal cancer that has spread to the liver when surgery is not an option. The radioactive beads dissolve and disappear in a few weeks. Limited information is available about how effective this approach is, but some studies suggest that it may help slow the growth of cancer cells. This procedure is performed by an interventional radiologist.

Radiation therapy for rectal cancer. For rectal cancer, radiation therapy may be used before surgery, called neoadjuvant therapy, to shrink the tumor so that it is easier to remove. It may also be used after surgery to destroy any remaining cancer cells. Both approaches have worked to treat this disease. Chemotherapy is often given at the same time as radiation therapy to increase the effectiveness of the radiation therapy. This is called chemoradiation therapy.

Chemoradiation therapy is often used in rectal cancer before surgery to avoid colostomy or reduce the chance that the cancer will recur. One study found that chemoradiation therapy before surgery worked better and caused fewer side effects than the same radiation therapy and chemotherapy given after surgery. The main benefits included a lower rate of the cancer coming back in the area where it started, fewer patients who needed permanent colostomies, and fewer problems with scarring of the bowel where the radiation therapy was given.

Radiation therapy is typically given in the United States for rectal cancer over 5.5 weeks before surgery. However, for certain patients (and in certain countries), a shorter course of 5 days of radiation therapy before surgery is appropriate and/or preferred.

A newer approach to rectal cancer is currently being used for many patients. It is called total neoadjuvant therapy (TNT). With TNT, both chemotherapy and chemoradiation therapy are given for about 6 months before surgery.

Side effects of radiation therapy

Talk with your doctor about the possible side effects of your radiation therapy regimen. Side effects from radiation therapy may include fatigue, mild skin reactions, upset stomach, and loose bowel movements. It may also cause bloody stools from bleeding through the rectum or blockage of the bowel. Most side effects go away soon after treatment is finished.

Sexual health problems, as well as infertility (the inability to have a child), may occur after radiation therapy to the pelvis. Before treatment begins, talk with your doctor about the chances that the treatment will affect sexual health and fertility and the available options for preserving fertility.

Learn more about the basics of radiation therapy.

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Therapies using medication

The treatment plan may include medications to destroy cancer cells. Medication may be given through the bloodstream to reach cancer cells throughout the body. When a drug is given this way, it is called systemic therapy. Medication may also be given locally, which is when the medication is applied directly to the cancer or kept in a single part of the body.

This type of medication is generally prescribed by a medical oncologist, a doctor who specializes in treating cancer with medication.

Medications are often given through an intravenous (IV) tube placed into a vein using a needle or as a pill or capsule that is swallowed (orally). If you are given oral medications to take at home, be sure to ask your health care team about how to safely store and handle them.

The types of medications used for colorectal cancer include:

  • Chemotherapy

  • Targeted therapy

  • Immunotherapy

Each of these types of therapies is discussed below in more detail. A person may receive 1 type of medication at a time or a combination of medications given at the same time. They can also be given as part of a treatment plan that includes surgery and/or radiation therapy.

The medications used to treat cancer are continually being evaluated. Talking with your doctor is often the best way to learn about the medications prescribed for you, their purpose, and their potential side effects or interactions with other medications.

It is also important to let your doctor know if you are taking any other prescription or over-the-counter medications or supplements. Herbs, supplements, and other drugs can interact with cancer medications, causing unwanted side effects or reduced effectiveness. Learn more about your prescriptions by using searchable drug databases.

Chemotherapy

Chemotherapy is the use of drugs to destroy cancer cells, usually by keeping the cancer cells from growing, dividing, and making more cells.

A chemotherapy regimen, or schedule, usually consists of a specific number of cycles given over a set period of time. A patient may receive 1 drug at a time or a combination of different drugs given at the same time.

Chemotherapy may be given after surgery to eliminate any remaining cancer cells. For some people with rectal cancer, the doctor will give chemotherapy and radiation therapy before surgery to reduce the size of a rectal tumor and reduce the chance of the cancer returning.

Many drugs are approved by the U.S. Food and Drug Administration (FDA) to treat colorectal cancer in the United States. Your doctor may recommend 1 or more of them at different times during treatment. Sometimes these are combined with targeted therapy drugs (see “Targeted therapy” below).

  • Capecitabine (Xeloda)

  • Fluorouracil (5-FU)

  • Irinotecan (Camptosar)

  • Oxaliplatin (Eloxatin)

  • Trifluridine/tipiracil (Lonsurf)

Some common treatment regimens using these drugs include:

  • 5-FU alone

  • 5-FU with leucovorin (folinic acid), a vitamin that improves the effectiveness of 5-FU

  • Capecitabine, an oral form of 5-FU

  • FOLFOX: 5-FU with leucovorin and oxaliplatin

  • FOLFIRI: 5-FU with leucovorin and irinotecan

  • Irinotecan alone

  • FOLFOXIRI: 5-FU with leucovorin, oxaliplatin, and irinotecan

  • XELOX/CAPEOX: Capecitabine with oxaliplatin

  • Use of a targeted therapy in combination with chemotherapy may be recommended: bevacizumab (Avastin), cetuximab (Erbitux), or panitumumab (Vectibix).

Side effects of chemotherapy

Chemotherapy may cause vomiting, nausea, diarrhea, mouth sores, or neuropathy, which is tingling or numbness in feet or hands. However, medications to prevent these side effects are available. Because of the way drugs are given, these side effects are less severe than they have been in the past for most people. In addition, patients may be unusually tired or fatigued, and there is an increased risk of infection. Major hair loss is an uncommon side effect with many of the drugs used to treat colorectal cancer, although it is more common with chemotherapy regimens that include irinotecan.

If side effects are particularly difficult, the dose of the drug may be lowered or a treatment session may be postponed. If you are receiving chemotherapy, you should regularly talk with your health care team about any side effects and ask which symptoms and side effects your doctor should know about right away. Read more about managing side effects. The side effects from chemotherapy usually go away after treatment is finished.

Learn more about the basics of chemotherapy.

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Targeted therapy

Targeted therapy is a treatment that targets the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival. This type of treatment blocks the growth and spread of cancer cells and limits damage to healthy cells.

Not all tumors have the same targets. To find the most effective treatment, your doctor may run tests to identify the genes, proteins, and other factors in your tumor. This helps doctors better match each patient with the most effective treatment whenever possible. In addition, research studies continue to find out more about specific molecular targets and new treatments directed at them. These drugs are becoming more important in the treatment of colorectal cancer. Learn more about the basics of targeted treatments.

Studies have shown that older patients are able to benefit from targeted therapies, similar to younger patients. In addition, the expected side effects are usually manageable in both older and younger patients.

For colorectal cancer, the following targeted therapies may be options.

Anti-angiogenesis therapy. Anti-angiogenesis therapy is focused on stopping angiogenesis, which is the process of making new blood vessels. Because a tumor needs the nutrients delivered by blood vessels to grow and spread, the goal of anti-angiogenesis therapies is to “starve” the tumor. The medications described below block a protein called VEGF, which is involved in the development of new blood vessels. They may also be called VEGF inhibitors.

  • Bevacizumab (Avastin). When bevacizumab is given with chemotherapy, it can help people with advanced colorectal cancer live longer. In 2004, the FDA approved bevacizumab along with chemotherapy as the first treatment, or first-line treatment, for advanced colorectal cancer. Recent studies have shown it is also effective as second-line therapy along with chemotherapy. There are 2 drugs similar to bevacizumab, bevacizumab-awwb (Mvasi) and bevacizumab-bvzr (Zirabev), that have also been approved by the FDA to treat advanced colorectal cancer. These are called biosimilars.

  • Fruquintinib (Fruzaqla). Fruquintinib may be used to treat people with metastatic colorectal cancer who have previously received chemotherapy and targeted therapy. This drug targets several VEGF receptors, which may explain why it still works for people who have already received treatment with a different VEGF inhibitor, such as bevacizumab. Fruquintinib is the latest targeted therapy to be approved in many years for treating advanced colorectal cancer that does not require a specific genetic mutation.

  • Regorafenib (Stivarga). This drug is used to treat people with metastatic colorectal cancer who have already received certain types of chemotherapy and other targeted therapies.

  • Ziv-aflibercept (Zaltrap) and ramucirumab (Cyramza). Either of these drugs can be combined with FOLFIRI chemotherapy as a second-line treatment for metastatic colorectal cancer.

Epidermal growth factor receptor (EGFR) inhibitors. Researchers have found that drugs that block EGFR may be effective for stopping or slowing the growth of colorectal cancer.

  • Cetuximab (Erbitux)

  • Panitumumab (Vectibix)

Recent studies show that cetuximab and panitumumab do not work as well for tumors that have specific changes, called mutations or alterations, to a gene called RAS. ASCO recommends that all people with metastatic colorectal cancer who may receive an EGFR inhibitor have their tumors tested for RAS and RAF gene mutations. If a tumor has a mutated form of the RAS gene or a specific BRAF mutation called V600E, ASCO recommends that they do not receive EGFR inhibitors. Research has also shown that these drugs do not work for HER2-positive colorectal cancer.

Combined targeted therapies. Some tumors have a specific mutation, called BRAF V600E, that can be detected by an FDA-approved test. A class of targeted treatments called BRAF inhibitors can be used to treat tumors with this mutation. A combination using the BRAF inhibitor encorafenib (Braftovi) and the EGFR inhibitor cetuximab may be used to treat people with metastatic colorectal cancer with this mutation who have received at least 1 previous treatment.

HER2-targeted therapy. Some tumors express a protein called HER2 that can be targeted by specific medications. If this happens, the cancer is called HER2-positive. For people with HER2-positive advanced colorectal cancer, treatment with a combination of tucatinib (Tukysa) and trastuzumab (Herceptin and other brand names) may be an option. This combination may only be used if there are no mutations in the RAS gene, surgery is not an option, and chemotherapy has stopped working and/or caused side effects that require stopping treatment. It also appears that HER2-targeted therapies do not work as well in tumors with PIK3CA mutations, so if your cancer has this, discuss with your doctor whether HER2-targeted therapy is right for you.

Tumor-agnostic treatment. Larotrectinib (Vitrakvi) and entrectinib (Rozlytrek) are types of targeted therapy that are not specific to a certain type of cancer but focus on a specific genetic change called an NTRK fusion. This type of genetic change is rare but is found in a range of cancers, including colorectal cancer. These medications are approved as treatment for colorectal cancer that is metastatic or cannot be removed with surgery and has worsened with other treatments.

The tumor may also be tested for other molecular markers, including PIK3CA mutations and others. These markers do not have FDA-approved targeted therapies yet, but there may be opportunities to receive treatment in clinical trials that are studying these molecular changes.

Side effects of targeted therapies

Talk with your doctor about possible side effects for a specific medication and how they can be managed. The side effects of targeted treatments can include a rash to the face and upper body, which can be prevented or reduced with various treatments. Find out more about skin reactions to targeted therapies.

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Immunotherapy

Immunotherapy uses the body's natural defenses to fight cancer by improving your immune system’s ability to attack cancer cells.

Checkpoint inhibitors are an important type of immunotherapy used to treat colorectal cancer. Learn more about the basics of immunotherapy.

  • Pembrolizumab (Keytruda). Pembrolizumab targets PD-1, a receptor on tumor cells, preventing the tumor cells from hiding from the immune system. Pembrolizumab is used to treat unresectable or metastatic colorectal cancers that have a molecular feature called microsatellite instability (MSI-H) or mismatch r.epair deficiency (dMMR) (see Diagnosis). Unresectable means surgery is not an option.

  • Nivolumab (Opdivo). Nivolumab is used to treat people who are 12 or older and have MSI-H or dMMR metastatic colorectal cancer that has grown or spread after treatment with chemotherapy with a fluoropyrimidine (such as capecitabine and fluorouracil), oxaliplatin, and irinotecan.

  • Dostarlimab (Jemperli). Dostarlimab is a PD-1 immune checkpoint inhibitor. It may be used to treat recurrent or metastatic colorectal cancers that have dMMR.

  • Nivolumab and ipilimumab (Yervoy) combination. This combination of checkpoint inhibitors is approved to treat patients who are 12 or older and have MSI-H or dMMR metastatic colorectal cancer that has grown or spread after treatment with chemotherapy with a fluoropyrimidine, oxaliplatin, and irinotecan.

Side effects of immunotherapies

Different types of immunotherapy can cause different side effects. The most common side effects of immunotherapy may include fatigue, rash, diarrhea, nausea, fever, muscle pain, bone pain, joint pain, abdominal pain, itching, vomiting, cough, decreased appetite, and shortness of breath. Immunotherapy can increase the risk of inflammation in different organs in your body. Talk with your doctor about possible side effects for the immunotherapy recommended for you and what symptoms to watch for.

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Physical, emotional, social, and financial effects of cancer

Cancer and its treatment cause physical symptoms and side effects, as well as emotional, social, and financial effects. Managing all of these effects is called palliative and supportive care. It is an important part of your care that is included along with treatments intended to slow, stop, or eliminate the cancer.

Palliative and supportive care focuses on improving how you feel during treatment by managing symptoms and supporting patients and their families with other, non-medical needs. Any person, regardless of age or type and stage of cancer, may receive this type of care. And it often works best when it is started right after a cancer diagnosis. People who receive palliative and supportive care along with treatment for the cancer often have less severe symptoms, better quality of life, and report that they are more satisfied with treatment.

Palliative treatments vary widely and often include medication, nutritional changes, relaxation techniques, emotional and spiritual support, and other therapies. You may also receive palliative treatments, such as chemotherapy, surgery, or radiation therapy, to improve symptoms.

Before treatment begins, talk with your doctor about the goals of each treatment in the recommended treatment plan. You should also talk about the possible side effects of the specific treatment plan and palliative and supportive care options. Many patients also benefit from talking with a social worker and participating in support groups. Ask your doctor about these resources, too.

Cancer care is often expensive, and navigating health insurance can be difficult. Ask your doctor or another member of your health care team about talking with a financial navigator or counselor who may be able to help with your financial concerns.

During treatment, your health care team may ask you to answer questions about your symptoms and side effects and to describe each problem. Be sure to tell the health care team if you are experiencing a problem. This helps the health care team treat any symptoms and side effects as quickly as possible. It can also help prevent more serious problems in the future.

Learn more about the importance of tracking side effects in another part of this guide. Learn more about palliative and supportive care in a separate section of this website.

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Treatment by stage of colorectal cancer

Different treatments may be recommended for each stage of colorectal cancer. The general options by stage are described below. For more detailed descriptions, see “How colorectal cancer is treated,” above. Your doctor will work with you to develop a specific treatment plan based on your specific diagnosis and needs. Clinical trials may also be a treatment option for each stage.

In general, stages 0, I, II, and III are often curable with surgery. However, many people with stage III colorectal cancer, and some with stage II, receive chemotherapy after surgery to increase the chance of eliminating the disease. People with stage II and III rectal cancer will also receive radiation therapy with chemotherapy either before or after surgery. Stage IV is not often curable, but it is treatable, and the growth of the cancer and the symptoms of the disease can be managed.

Stage 0 colorectal cancer

The usual treatment is a polypectomy, or removal of a polyp, during a colonoscopy. There is no additional surgery unless the polyp cannot be fully removed.

Stage I colorectal cancer

Surgical removal of the tumor and lymph nodes is usually the only treatment needed.

Stage II colorectal cancer

Surgery is often the first treatment. People with stage II colorectal cancer should talk with their doctor about whether more treatment is needed after surgery because in some cases adjuvant chemotherapy may be recommended. Adjuvant chemotherapy is treatment after surgery with the goal of trying to destroy any remaining cancer cells. ASCO does not recommend adjuvant chemotherapy for many people with stage II colon cancer. Cure rates for surgery alone are quite good, and there are limited benefits of additional treatment for many people with this stage of colon cancer. However, adjuvant chemotherapy may be recommended for some people with cancer that has invaded nearby organs, penetrated through the entire bowel wall, or has features that indicate a high risk of recurrence. Talk with your doctors about the risks and benefits of adjuvant chemotherapy. A clinical trial is also an option after surgery.

For stage II rectal cancer, radiation therapy is usually given in combination with chemotherapy, either before or after surgery. Additional chemotherapy may be given after surgery as well.

Stage III colorectal cancer

Treatment usually involves surgical removal of the tumor followed by adjuvant chemotherapy. A clinical trial may also an option. The duration of adjuvant therapy depends on the risk of recurrence (based on characteristics of the cancer that was removed at surgery). In determining duration of therapy, recent ASCO guidelines recommend a shared decision-making approach, taking into account patient characteristics, values and preferences, and other factors and including a discussion of the potential for benefit and risks of harm associated with duration.

For rectal cancer, radiation therapy may be used with chemotherapy before or after surgery, along with adjuvant chemotherapy.

Metastatic (stage IV) colorectal cancer

If cancer spreads to another part in the body from where it started, doctors call it metastatic cancer. Colorectal cancer can spread to distant organs, such as the liver, lungs, lymph nodes, ovaries, and the tissue called the peritoneum that lines the abdomen. If this happens, it is a good idea to talk with doctors who have experience treating this stage of cancer. Doctors can have different opinions about the best standard treatment plan. Clinical trials might also be an option. Learn more about getting a second opinion before starting treatment, so you are comfortable with your chosen treatment plan.

Your treatment plan may include a combination of chemotherapy, targeted therapy, immunotherapy, surgery, and radiation therapy, which can be used to slow the spread of the disease and shrink a cancerous tumor. Palliative and supportive care will also be important to help relieve symptoms of cancer and side effects of treatment.

For stage IV colorectal cancer, surgery to remove the portion of the colon where the cancer started is not generally recommended, but it may help relieve blockage of the colon or other problems related to the cancer. Surgery may also be used to remove parts of other organs that contain cancer, called resection, and can cure some people if a limited amount of cancer spreads to a single organ, such as the liver or a lung.

For people with metastatic colorectal cancer that does not have dMMR or MSI-H (see above) and cannot initially be treated by surgery, ASCO recommends starting with FOLFOX, FOLFIRI, or CAPOX chemotherapy. For some people, FOLFOXIRI may be recommended instead.

For individuals with left-sided colorectal cancer that is not dMMR/MSI-H and has no mutations in the RAS or BRAF genes or HER2 overexpression, treatment should begin with an EGFR inhibitor combined with a chemotherapy regimen using 2 drugs.

For people with metastatic colorectal cancer with dMMR or MSI-H, ASCO recommends starting treatment with immunotherapy using pembrolizumab.

If the cancer has not been stopped by the initial treatment and the cancer has a BRAF V600E mutation, then combination targeted therapies using encorafenib plus cetuximab may be recommended.

If the colorectal cancer has spread to the peritoneum, then surgery to reduce the size of the tumors combined with chemotherapy may be recommended.

If the colorectal cancer has spread only to the liver and if surgery is possible—either before or after chemotherapy—there is a chance of complete cure. Even when curing the cancer is not possible, surgery may add months or even years to a person’s life. Sometimes the surgery may be combined with chemotherapy. Determining who can benefit from surgery for cancer that has spread to the liver is often a complicated process that involves multiple doctors with different specialties working together to plan the best treatment option. If surgery is not an option for colorectal cancer that has spread to the liver, then radiation therapy may be offered instead.

For many people, a diagnosis of metastatic cancer is very stressful and difficult. You and your family are encouraged to talk about how you feel with doctors, nurses, social workers, or other members of your health care team. It may also be helpful to talk with other patients, such as through a support group or other peer support program.

This information is based on the ASCO guideline, “Treatment of Metastatic Colorectal Cancer.” Please note that this link takes you to a separate ASCO website.

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Remission and the chance of recurrence

A remission is when cancer cannot be detected in the body and there are no symptoms. This may also be called having “no evidence of disease” or NED.

A remission may be temporary or permanent. This uncertainty causes many people to worry that the cancer will come back. While many remissions are permanent, it is important to talk with your doctor about the possibility of the cancer returning. Understanding your risk of recurrence and the treatment options may help you feel more prepared if the cancer does return. Learn more about coping with the fear of recurrence.

If the cancer returns after the original treatment, it is called recurrent cancer. It may come back in the same place (called a local recurrence), nearby (regional recurrence), or in another place (distant recurrence).

If a recurrence happens, a new cycle of testing will begin to learn as much as possible about it. After this testing is done, you and your doctor will talk about the treatment options. Often the treatment plan may include the treatments described above, such as surgery, radiation therapy, chemotherapy, immunotherapy, or targeted therapy, but they may be used in a different combination and will depend on molecular characteristics of your cancer and how your body is doing overall. Your doctor may suggest clinical trials that are studying new ways to treat recurrent colorectal cancer. Generally, the treatment options for recurrent cancer are the same as those for metastatic cancer. Whichever treatment plan you choose, palliative and supportive care will be important for relieving symptoms and side effects.

People with recurrent cancer sometimes experience emotions such as disbelief or fear. You are encouraged to talk with your health care team about these feelings and ask about support services to help you cope. Learn more about dealing with cancer recurrence.

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If treatment does not work

Recovery from cancer is not always possible. If the cancer cannot be cured or controlled, the disease may be called advanced or terminal.

This diagnosis is stressful, and for some people, advanced cancer is difficult to discuss. However, it is important to have open and honest conversations with your health care team to express your feelings, preferences, and concerns. The health care team has special skills, experience, and knowledge to support patients and their families and is there to help. Making sure a person is physically comfortable, free from pain, and emotionally supported is extremely important.

Planning for your future care and putting your wishes in writing is important, especially at this stage of disease. Then, your health care team and loved ones will know what you want, even if you are unable to make these decisions. Learn more about putting your health care wishes in writing.

People who have advanced cancer and who are expected to live less than 6 months may want to consider hospice care. Hospice care is designed to provide the best possible quality of life for people who are near the end of life. You and your family are encouraged to talk with the health care team about hospice care options, which include hospice care at home, a special hospice center, or other health care locations. Nursing care and special equipment can make staying at home a workable option for many families. Learn more about advanced cancer care planning.

After the death of a loved one, many people need support to help them cope with the loss. Learn more about grief and loss.

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The next section in this guide is About Clinical Trials. It offers more information about research studies that are focused on finding better ways to care for people with cancer. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - About Clinical Trials

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will learn more about clinical trials, which are the main way that new medical approaches are studied to see how well they work. Use the menu to see other pages.

What are clinical trials?

Doctors and scientists are always looking for better ways to care for people with colorectal cancer. To make scientific advances, doctors create research studies involving volunteers, called clinical trials. Every drug that is now approved by the U.S. Food and Drug Administration (FDA) was tested in clinical trials.

Clinical trials are used for all types and stages of colorectal cancer. Many focus on new treatments to learn if a new treatment is safe, effective, and possibly better than the existing treatments. These types of studies evaluate new drugs, different combinations of treatments, new approaches to radiation therapy or surgery, and new methods of treatment.

People who participate in clinical trials can be some of the first to get a treatment before it is available to the public. However, there are some risks with a clinical trial, including possible side effects and the chance that the new treatment may not work. People are encouraged to talk with their health care team about the pros and cons of joining a specific study.

Some clinical trials study new ways to relieve symptoms and side effects during treatment. Others study ways to manage the late effects that may happen a long time after treatment. Talk with your doctor about clinical trials for symptoms and side effects.

Deciding to join a clinical trial

People decide to participate in clinical trials for many reasons. For some, a clinical trial is the best treatment option available. Because standard treatments are not perfect, patients are often willing to face the added uncertainty of a clinical trial in the hope of a better result. Others volunteer for clinical trials because they know that these studies are a way to contribute to the progress in treating colorectal cancer. Even if they do not benefit directly from the clinical trial, their participation may benefit future people with colorectal cancer.

Insurance coverage and the costs of clinical trials differ by location and by study. In some programs, some of the expenses from participating in the clinical trial are reimbursed. In others, they are not. It is important to talk with the research team and your insurance company first to learn if and how your treatment in a clinical trial will be covered. Learn more about health insurance coverage of clinical trials.

Sometimes people have concerns that, in a clinical trial, they may receive no treatment by being given a placebo or a “sugar pill.” When used, placebos are usually combined with standard treatment in most cancer clinical trials. Study participants will always be told when a placebo is used in a study. Find out more about placebos in cancer clinical trials.

Patient safety and informed consent

To join a clinical trial, people must participate in a process known as informed consent. During informed consent, the doctor should:

  • Describe all of the treatment options, so that the person understands how the new treatment differs from the standard treatment.

  • List all of the risks of the new treatment, which may or may not be different from the risks of standard treatment.

  • Explain what will be required of each person in order to participate in the clinical trial, including the number of doctor visits, tests, and the schedule of treatment.

  • Describe the purposes of the clinical trial and what researchers are trying to learn.

Clinical trials also have certain rules called “eligibility criteria” that help structure the research and keep patients safe. You and the research team will carefully review these criteria together. You will need to meet all of the eligibility criteria in order to participate in a clinical trial. Learn more about eligibility criteria in clinical trials.

People who participate in a clinical trial may stop participating at any time for personal or medical reasons. This may include that the new treatment is not working or there are serious side effects. Clinical trials are also closely monitored by experts who watch for any problems with each study. It is important that people participating in a clinical trial talk with their doctor and researchers about who will be providing their treatment and care during the clinical trial, after the clinical trial ends, and/or if they choose to leave the clinical trial before it ends.

Finding a clinical trial

Research through clinical trials is ongoing for all types of cancer. For specific topics being studied for colorectal cancer, learn more in the Latest Research section.

Cancer.Net offers more information about cancer clinical trials in other areas of the website, including a complete section on clinical trials.

There are many resources and services to help you search for clinical trials for colorectal cancer, including the following services. Please note that these links will take you to separate, independent websites:

  • ClinicalTrials.gov. This U.S. government database lists publicly and privately supported clinical trials.

  • World Health Organization (WHO) International Clinical Trials Registry Platform. The WHO coordinates health matters within the United Nations. This search portal gathers clinical trial information from many countries’ registries.

Read more about the basics of clinical trials matching services.

PRE-ACT, Preparatory Education About Clinical Trials

In addition, you can find a free video-based educational program about cancer clinical trials in another section of this website.

The next section in this guide is Latest Research. It explains areas of scientific research for colorectal cancer. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Latest Research

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will read about the scientific research being done to learn more about colorectal cancer and how to treat it. Use the menu to see other pages.

Doctors are working to learn more about colorectal cancer, ways to prevent it, how to best treat it, and how to provide the best care to people diagnosed with this disease. The following areas of research may include new options for patients through clinical trials. Always talk with your doctor about the best diagnostic and treatment options for you.

  • Improved detection methods. Researchers are developing tests to analyze stool samples and blood samples to find genetic changes associated with colorectal cancer. By finding and removing polyps or identifying cancer early, doctors have a better chance of curing the disease.

  • Tests to predict the risk of cancer recurrence. Various genes play important roles in the growth and spread of tumors. Tests to identify these genes can help doctors and patients decide whether to use chemotherapy after treatment. Researchers hope that these tests can help people with a lower risk of recurrence avoid the side effects of additional treatment.

  • Immunotherapy. In the past several years, researchers have discovered a class of drugs that targets the ways that tumor cells avoid the immune system. These immunotherapy drugs are called checkpoint inhibitors. The latest research has shown that certain checkpoint inhibitors, called PD-1 or PD-L1 inhibitors, can be effective against a type of metastatic colorectal cancer that is microsatellite high (MSI-H) or has mismatch repair deficiency (dMMR). There are ongoing clinical trials looking at combining checkpoint inhibitors with other drugs or cancer-directed treatments to see if they can be helpful in tumors that are not MSI-H.

  • Chemotherapy and targeted therapy. New types of chemotherapy and targeted therapy are being studied for colorectal cancer, including advanced colon and rectal cancers. Most of these newer drugs are only available through clinical trials.

  • Palliative and supportive care. Clinical trials are underway to find better ways of reducing symptoms and side effects of current colorectal cancer treatments to improve comfort and quality of life for patients.

Looking for More About the Latest Research?

If you would like more information about the latest areas of research in colorectal cancer, explore these related items that take you outside of this guide:

The next section in this guide is Coping with Treatment. It offers some guidance on how to cope with the physical, emotional, social, and financial changes that cancer and its treatment can bring. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Coping with Treatment

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will learn more about coping with the physical, emotional, social, and financial effects of cancer and its treatment. Use the menu to see other pages.

Every cancer treatment can cause side effects or changes to your body and how you feel. For many reasons, people do not experience the same side effects even when they are given the same treatment for the same type of cancer. This can make it hard to predict how you will feel during treatment.

READ MORE BELOW:

As you prepare to start cancer treatment, it is normal to fear treatment-related side effects. It may help to know that your health care team will work to prevent and relieve side effects. This part of cancer treatment is called palliative and supportive care. It is an important part of your treatment plan, regardless of your age or the stage of disease.

Coping with physical side effects

Common physical side effects from each treatment option for colorectal cancer are described in the Types of Treatment section. Learn more about side effects of cancer and its treatment, along with ways to prevent or control them. Changes to your physical health depend on several factors, including the cancer’s stage, the length and dose of treatment, and your general health.

Many people who have been treated for colorectal cancer have difficulty eating at some point during treatment. Listen to a podcast about managing eating challenges after colorectal cancer treatment.

Talk with your health care team regularly about how you are feeling. It is important to let them know about any new side effects or changes in existing side effects. If they know how you are feeling, they can find ways to relieve or manage your side effects to help you feel more comfortable and potentially keep any side effects from worsening.

You may find it helpful to keep track of your side effects so it is easier to talk about any changes with your health care team. Learn more about why tracking side effects is helpful.

Sometimes, side effects can last after treatment ends. Doctors call these long-term side effects. Side effects that occur months or years after treatment are called late effects. Treating long-term side effects and late effects is an important part of survivorship care. Learn more by reading the Follow-up Care section of this guide or talking with your doctor.

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Coping with emotional and social effects

You can have emotional and social effects after a cancer diagnosis. This may include dealing with a variety of emotions, such as sadness, anxiety, fear, or anger, or managing stress. Sometimes, people find it difficult to express how they feel to their loved ones. Some have found that talking to an oncology social worker, counselor, or member of the clergy can help them develop more effective ways of coping and talking about cancer.

You can also find coping strategies for emotional and social effects in a separate section of this website. This section includes many resources for finding support and information to meet your needs.

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Coping with the costs of cancer care

Cancer treatment can be expensive. It may be a source of stress and anxiety for people with cancer and their families. In addition to treatment costs, many people find they have extra, unplanned expenses related to their care. For some people, the high cost of medical care stops them from following or completing their cancer treatment plan. This can put their health at risk and may lead to higher costs in the future. Patients and their families are encouraged to talk about financial concerns with a member of their health care team. Learn more about managing financial considerations in a separate part of this website.

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Coping with barriers to care

Some groups of people experience different rates of new cancer cases and experience different outcomes from their cancer diagnosis. These differences are called “cancer disparities.” Disparities are caused in part by real-world barriers to quality medical care and social determinants of health, such as where a person lives and whether they have access to food and health care. Cancer disparities more often negatively affect racial and ethnic minorities, people with fewer financial resources, sexual and gender minorities (LGBTQ+), adolescent and young adult populations, adults older than 65, and people who live in rural areas or other underserved communities.

If you are having difficulty getting the care you need, talk with a member of your health care team or explore other resources that help support medically underserved people.

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Talking with your health care team about side effects

Before starting treatment, talk with your doctor about possible side effects. Ask:

  • Which side effects are most likely?

  • When are they likely to happen?

  • What can we do to prevent or relieve them?

  • When and who should I call about side effects?

Be sure to tell your health care team about any side effects that happen during treatment and afterward, too. Tell them even if you do not think the side effects are serious. This discussion should include physical, emotional, social, and financial effects of cancer.

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Caring for a loved one with colorectal cancer

Family members and friends often play an important role in taking care of a person with colorectal cancer. This is called being a caregiver. Caregivers can provide physical, practical, and emotional support to the patient, even if they live far away. Being a caregiver can also be stressful and emotionally challenging. One of the most important tasks for caregivers is caring for themselves.

Caregivers may have a range of responsibilities on a daily or as-needed basis, including:

  • Providing support and encouragement

  • Talking with the health care team

  • Giving medications

  • Helping manage symptoms and side effects

  • Coordinating medical appointments

  • Providing a ride to and from appointments

  • Assisting with meals

  • Helping with household chores

  • Handling insurance and billing issues

A caregiving plan can help caregivers stay organized and help identify opportunities to delegate tasks to others. It may be helpful to ask the health care team how much care will be needed at home and with daily tasks during and after treatment. Use this 1-page fact sheet to help make a caregiving action plan. This free fact sheet is available as a PDF, so it is easy to print.

Learn more about caregiving or read the ASCO Answers Guide to Caring for a Loved One With Cancer in English or Spanish.

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Looking for More on How to Track Side Effects?

Cancer.Net offers several resources to help you keep track of your symptoms and side effects. Please note that these links will take you to other sections of Cancer.Net:

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The next section in this guide is Follow-up Care. It explains the importance of checkups after you finish cancer treatment. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Follow-Up Care

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will read about your medical care after cancer treatment is completed and why this follow-up care is important. Use the menu to see other pages.

Care for people diagnosed with cancer does not end when active treatment has finished. Your health care team will continue to check to make sure the cancer has not come back, manage any side effects, and monitor your overall health. This is called follow-up care.

Your follow-up care may include regular physical examinations, medical tests, or both. Doctors want to keep track of your recovery in the months and years ahead. Follow-up care is especially important in the first 5 years after treatment for colorectal cancer because this is when the risk of recurrence is highest.

Cancer rehabilitation may be recommended, and this could mean any of a wide range of services, such as physical therapy, occupational therapy, career counseling, pain management, nutritional planning, and/or emotional counseling. The goal of rehabilitation is to help people regain control over many aspects of their lives and remain as independent as possible. Learn more about cancer rehabilitation.

Learn more about the importance of follow-up care.

Watching for recurrence

One goal of follow-up care is to check for a recurrence, which means that the cancer has come back. Cancer recurs because small areas of cancer cells may remain undetected in the body. Over time, these cells may increase in number until they show up on test results or cause signs or symptoms. During follow-up care, a doctor familiar with your medical history can give you personalized information about your risk of recurrence. Your doctor will ask specific questions about your health. Some people may have blood tests or imaging tests done as part of regular follow-up care, but testing recommendations depend on several factors, including the type and stage of cancer first diagnosed and the types of treatment given.

The anticipation before having a follow-up test or waiting for test results may add stress to you or a family member. This is sometimes called “scanxiety.” Learn more about how to cope with this type of stress.

Recommended follow-up care for colorectal cancer

The tests your doctor recommends and how often you need to have them will be based on your risk of recurrence and your overall health. In general, it is common for a patient to visit the doctor and receive follow-up screening every 3 to 6 months for 5 years after diagnosis. It is important to remember that different people have different risks of recurrence, so it is important to talk with your doctor about the possibility of the cancer coming back.

ASCO has recommendations for follow-up care for people who had stage II or stage III colorectal cancer. It is less certain what testing should be done for people who had stage I colorectal cancer because this stage is less likely to come back. If you have had treatment for metastatic colorectal cancer, it is important to talk with your doctor about creating a survivorship care plan specifically for you, since there is currently no standardized follow-up care schedule for this stage of colorectal cancer. It is also important to remember that these follow-up care recommendations are for people who had colorectal cancer that was not inherited (see Risk Factors).

First year after treatment

  • Physical examination and carcinoembryonic antigen (CEA) testing every 3 to 6 months

  • Abdominal and chest computed tomography (CT) scan each year (every 6 to 12 months for people with a high risk of recurrence)

  • For people with rectal cancer, pelvic CT scan every 6 to 12 months

  • Colonoscopy 1 year after surgery (the results of this colonoscopy will guide if or when future colonoscopies will be needed)

  • Rectosigmoidoscopy every 6 months for people with rectal cancer who did not have radiation therapy to the pelvis.

Second year after treatment

  • Physical examination and CEA testing every 3 to 6 months

  • CT scan each year (every 6 to 12 months for people with a high risk of recurrence)

  • For people with rectal cancer, pelvic CT scan every 6 to 12 months

  • Rectosigmoidoscopy every 6 months for people with rectal cancer who did not have radiation therapy to the pelvis

Third year after treatment

  • Physical examination and CEA testing every 3 to 6 months

  • CT scan each year (every 6 to 12 months for people with a high risk of recurrence)

  • For people with rectal cancer, pelvic CT scan every 6 to 12 months

  • Rectosigmoidoscopy every 6 months for people with rectal cancer who did not have radiation therapy to the pelvis

Fourth year after treatment

  • Physical examination and CEA testing every 3 to 6 months

  • For people with rectal cancer, pelvic CT scan each year

  • Rectosigmoidoscopy every 6 months for people with rectal cancer who did not have radiation therapy to the pelvis

Fifth year after treatment

  • Physical examination and CEA testing every 3 to 6 months

  • For people with rectal cancer, pelvic CT scan each year

  • Rectosigmoidoscopy every 6 months for people with rectal cancer who did not have radiation therapy to the pelvis

This information is based on the ASCO endorsement of the Cancer Care Ontario guideline, "Follow-Up Care, Surveillance Protocol, and Secondary Prevention Measures for Survivors of Colorectal Cancer Endorsement." Note that this link takes you to a different ASCO website.

Managing long-term and late side effects

Most people expect to have side effects when receiving treatment. However, it is often surprising to survivors that some side effects may linger beyond the treatment period. These are called long-term side effects. Other side effects called late effects may develop months or even years after treatment has ended. Long-term and late effects can include both physical and emotional changes.

Talk with your doctor about your risk of developing such side effects based on your diagnosis, your individual treatment plan, and your overall health. If you had a treatment known to cause specific late effects, you may have certain physical examinations, scans, or blood tests to help find and manage them.

Keeping personal health records

You and your doctor should work together to develop a personalized follow-up care plan. Be sure to discuss any concerns you have about your future physical or emotional health. The American Society of Clinical Oncology (ASCO) offers forms to help keep track of the cancer treatment you received and develop a survivorship care plan when treatment is completed.

This is also a good time to talk with your doctor about who will lead your follow-up care. Some survivors continue to see their oncologist, while others transition back to the care of their primary care doctor or another health care professional. This decision depends on several factors, including the type and stage of cancer, treatments received, side effects, health insurance rules, and your personal preferences.

If a doctor who was not directly involved in your cancer care will lead your follow-up care, be sure to share your cancer treatment summary and survivorship care plan forms with them and with all future health care providers. Details about your cancer treatment are very valuable to the health care professionals who will care for you throughout your lifetime.

The next section in this guide is Survivorship. It describes how to cope with challenges in everyday life after a cancer diagnosis. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Survivorship

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will read about how to cope with challenges in everyday life after a cancer diagnosis. Use the menu to see other pages.

What is survivorship?

The word “survivorship” is complicated because it means different things to different people. Common definitions include:

  • Having no signs of cancer after finishing treatment.

  • Living with, through, and beyond cancer. According to this definition, cancer survivorship begins at diagnosis and continues during treatment and through the rest of a person's life.

For some, the term “survivorship” itself does not feel right, and they may prefer to use different language to describe and define their experience. Sometimes long-term treatment will be used for months or years to manage or control cancer. Living with cancer indefinitely is not easy, and the health care team can help you manage the challenges that come with it. Everyone has to find their own path to name and navigate the changes and challenges that are the results of their cancer diagnosis and treatment.

Survivors may experience a mixture of feelings, including joy, concern, relief, guilt, and fear. Some people say they appreciate life more after a cancer diagnosis and have gained a greater acceptance of themselves. Others become very anxious about their health and uncertain about coping with everyday life. Feelings of fear and anxiety may still occur as time passes, but these emotions should not be a constant part of your daily life. If they persist, be sure to talk with a member of your health care team.

Survivors may feel some stress when their frequent visits to the health care team end after completing treatment. Often, relationships built with the cancer care team provide a sense of security during treatment, and people miss this source of support. This may be especially true when new worries and challenges surface over time, such as any late effects of treatment, emotional challenges including fear of recurrence, sexual health and fertility concerns, and financial and workplace issues.

Every survivor has individual concerns and challenges. With any challenge, a good first step is being able to recognize your fears and talk about them. Effective coping requires:

  • Understanding the challenge you are facing

  • Thinking through solutions

  • Asking for and allowing the support of others

  • Feeling comfortable with the course of action you choose

Many survivors find it helpful to join an in-person support group or an online community of survivors. This allows you to talk with people who have had similar first-hand experiences. Other options for finding support include talking with a friend or member of your health care team, individual counseling, or asking for assistance at the learning resource center of the place where you received treatment.

A new perspective on your health

For many people, survivorship serves as a strong motivator to make lifestyle changes.

People recovering from colorectal cancer are encouraged to follow established guidelines for good health, such as not smoking, limiting alcohol, eating well, exercising regularly, maintaining a healthy weight, and managing stress.

Regular physical activity can help rebuild your strength and energy level. Research has also suggested that exercise may lower the risk of colorectal cancer recurrence and help people live longer, although more studies are underway to confirm this. Your health care team can help you create an appropriate exercise plan based upon your needs, physical abilities, and fitness level. Learn more about making healthy lifestyle choices.

It is important to have recommended medical checkups and tests (see Follow-up Care) to take care of your health.

Talk with your health care team to develop a survivorship care plan that is best for your needs.

Changing role of caregivers

Family members and friends may also go through periods of transition. A caregiver plays a very important role in supporting a person diagnosed with cancer, providing physical, emotional, and practical care on a daily or as-needed basis. Many caregivers become focused on providing this support, especially if the treatment period lasts for many months or longer.

However, as treatment is completed, the caregiver's role often changes. Eventually, the need for caregiving related to the cancer diagnosis will become much less or come to an end. Caregivers can learn more about adjusting to life after caregiving.

Looking for More Survivorship Resources?

For more information about cancer survivorship, explore these related items. Please note that these links will take you to other sections of Cancer.Net:

  • ASCO Answers Guide to Cancer Survivorship: Get this 48-page booklet that helps people transition into life after treatment. It includes blank treatment summary and survivorship care plan forms. The free booklet is available as a PDF, so it is easy to print.

  • Survivorship Resources: Cancer.Net offers information and resources to help survivors cope, including specific sections for children, teens and young adults, and people over age 65. There is also a main section on survivorship for people of all ages.

The next section offers Questions to Ask the Health Care Team to help start conversations with your cancer care team. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Questions to Ask the Health Care Team

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find some questions to ask your doctor or other members of the health care team, to help you better understand your diagnosis, treatment plan, and overall care. Use the menu to see other pages.

Talking often with the health care team is important to make informed decisions about your health care. These suggested questions are a starting point to help you learn more about your cancer care and treatment. You are also encouraged to ask additional questions that are important to you. You may want to print this list and bring it to your next appointment. It may also be helpful to ask a family member or friend to come with you to appointments to help take notes.

Questions to ask about choosing a treatment and managing side effects

  • What are my treatment options based on my diagnosis?

  • What types of research are being done for colorectal cancer in clinical trials? Do clinical trials offer additional treatment options for me?

  • What treatment plan do you recommend? Why?

  • What is the goal of each treatment? Is it to eliminate the cancer, help me feel better, or both?

  • What are the risks and possible side effects of each treatment, both in the short term and the long term?

  • Who will be part of my health care team, and what does each member do?

  • Who will be leading my overall treatment?

  • How will this treatment affect my daily life? Will I able to work, exercise, and perform my usual activities?

  • Could this treatment affect my sex life? If so, how and for how long?

  • Could this treatment affect my ability to become pregnant or have children? If so, should I talk with a fertility specialist before cancer treatment begins?

  • If I’m worried about managing the costs of cancer care, who can help me?

  • What support services are available to me? To my family?

  • If I have questions or problems, who should I call?

Questions to ask before surgery

  • Where exactly is the cancer located?

  • What do you know about my cancer at this point?

  • If I have rectal cancer, should I have radiation therapy and chemotherapy before my surgery?

  • What other tests will be done before surgery?

  • Can you describe the surgery I will be having?

  • What are you planning to remove during surgery? The colon, rectum, or lymph nodes?

  • Is a biopsy part of the surgery?

  • How soon after surgery will I have all test results and a firm diagnosis?

  • Do you think I may need a temporary or permanent colostomy?

  • Is this the standard type of surgery for my condition?

  • How many times have you performed this type of operation successfully?

  • Who will give me information about how I should get ready for surgery and a hospital stay? How long will I be in the hospital?

  • How will my pain be controlled after surgery?

  • What other side effects are possible with this type of surgery?

  • Can you describe what my recovery from surgery will be like?

Questions to ask after surgery

  • What is my diagnosis based on the results of surgery and biopsy reports, in TNM staging format?

  • Can you explain my pathology report (laboratory test results) to me?

  • Did the pathologist test my tumor for a possible genetic cause? Do I need genetic counseling or testing?

  • Does my diagnosis mean that my relatives have a higher risk of colorectal cancer? Should they talk with their doctors about screening?

  • Will the cancer be tested for mutations or other genetic features, like MSI-H or dMMR?

  • What is my prognosis?

  • How will additional treatment after surgery affect my prognosis?

  • What additional treatment do you recommend? Why?

  • What are the benefits and risks of adjuvant chemotherapy? How does it affect my prognosis?

  • What is the goal of each treatment?

  • Is it a standard treatment or part of a clinical trial?

  • How long will it be before I can go back to work after surgery?

  • If I need a colostomy, will you refer me to a specially trained nurse to decide on the best place for my colostomy and help me learn to manage it after the surgery?

  • Who should I contact about any side effects I experience? And how soon?

Questions to ask about having radiation therapy

  • What type of treatment is recommended?

  • What is the goal of this treatment?

  • How long will it take to give this treatment?

  • What side effects can I expect during treatment?

  • Who should I contact about any side effects I experience? And how soon?

  • What are the possible long-term or late effects of having this treatment?

  • What can be done to prevent or relieve the side effects?

Questions to ask about having therapies using medications

  • What type(s) of medication is recommended?

  • What is the goal of this treatment?

  • How long will it take to give this treatment?

  • Will I receive this treatment at a hospital or clinic? Or will I take it at home?

  • What side effects can I expect during treatment?

  • Who should I contact about any side effects I experience? And how soon?

  • What are the possible long-term or late effects of having this treatment?

  • What can be done to prevent or relieve the side effects?

Questions to ask about planning follow-up care

  • What is the chance that the cancer will come back? Should I watch for specific signs or symptoms?

  • How often will I need CEA testing? Where will it be done?

  • How often do I need a computed tomography (CT) scan? Where will it be done?

  • How often do I need a colonoscopy? Who will do it and where will it be done?

  • (Rectal cancer only) How often do I need a rectosigmoidoscopy?

  • What long-term side effects or late effects are possible based on the cancer treatment I received?

  • What follow-up tests will I need, and how often will those tests be needed?

  • What type of follow-up care do I need beyond 5 years after treatment?

  • How do I get a treatment summary and survivorship care plan to keep in my personal records?

  • When should I return to my primary care doctor for regular medical care?

  • Who will be leading my follow-up care?

  • What survivorship support services are available to me? To my family?

The next section in this guide is Additional Resources. It offers more resources on this website that may be helpful to you. Use the menu to choose a different section to read in this guide.

Colorectal Cancer - Additional Resources

Approved by the Cancer.Net Editorial Board, 09/2023

ON THIS PAGE: You will find some helpful links to other areas of Cancer.Net that provide information about cancer care and treatment. This is the final page of Cancer.Net’s Guide to Colorectal Cancer. To go back and review other pages, use the menu.

Cancer.Net includes many other sections about the medical and emotional aspects of cancer for the person diagnosed and their family members and friends. This website is meant to be a resource for you and your loved ones from the time of diagnosis, through treatment, and beyond.

Here are a few links to help you explore other parts of Cancer.Net:

This is the end of Cancer.Net’s Guide to Colorectal Cancer. Use the menu to go back and review other pages.