Treatment

The treatment of anal cancer depends on the size and location of the tumor, whether the cancer has spread, and the patient’s overall health, including whether the patient has HIV. In many cases, a team of doctors will work with the patient to determine the best treatment plan.

This section outlines treatments that are the standard of care (the best treatments available) for this specific type of cancer. Patients are also encouraged to consider clinical trials when making treatment plan decisions. A clinical trial is a research study to test a new treatment to prove it is safe, effective, and possibly better than standard treatment. Your doctor can help you review all treatment options. For more information, visit the Clinical Trials section.

For anal cancer, there are three main types of treatment: surgery, radiation therapy, and chemotherapy. Descriptions of each treatment option are listed below.

Surgery

The type of surgery for anal cancer depends on the stage of the cancer. A surgical oncologist is a doctor who specializes in treating cancer using surgery. Surgery for anal cancer may also be performed by a colorectal surgeon, who specializes in surgery on the colon or rectum. Anal carcinoma in situ or early-stage cancer can often be treated by removing the abnormal cells and a small area of the surrounding normal tissue (called a margin). Afterward, patients should receive regular follow-up screening to identify and remove any new abnormal cells.

Most patients with later stages of anal cancer were treated surgically before effective chemotherapy and radiation therapy were developed for anal cancer. However, studies have shown similar cure rates between surgical treatment and the combination of radiation therapy and chemotherapy. Now, most patients have a biopsy (which may require some level of surgery; see Diagnosis) followed by chemotherapy and radiation therapy without further surgery. Many patients can avoid major surgery with this type of combined treatment.

If a patient cannot have chemotherapy or radiation therapy, surgery may be recommended. Surgery may also be recommended if the cancer remains after initial treatment or returns after treatment has been completed. A persistent or recurring tumor may be treated with an abdominoperineal resection, which is the surgical removal of the anus, rectum, and part of the colon. This procedure results in a colostomy (an opening on the abdominal wall to allow feces to be collected in a bag). Lymph nodes may also be removed during this procedure. Learn more about cancer surgery.

Radiation therapy

Radiation therapy is the use of high-energy x-rays or other particles to kill cancer cells. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. The most common type of radiation treatment is called external-beam radiation therapy, which is radiation given from a machine outside the body. When radiation treatment is given using implants, it is called internal radiation therapy or brachytherapy.

Radiation therapy for anal cancer is often combined with chemotherapy. Patients with both anal cancer and HIV may be treated with lower doses of radiation therapy, depending on the degree the patient’s immune system is compromised by the HIV.

Side effects of radiation therapy may include fatigue, mild skin reactions, upset stomach, temporary anal irritation, loose bowel movements, and discomfort when having a bowel movement. Scar tissue may form from damage to anal tissue, which may interfere with bowel function. Most side effects go away soon after treatment is finished. Learn more about radiation therapy.

Chemotherapy

Chemotherapy is the use of drugs to kill cancer cells. Systemic chemotherapy is delivered through the bloodstream, targeting cancer cells throughout the body. Chemotherapy is given by a medical oncologist, a doctor who specializes in treating cancer with medication. Some people may receive chemotherapy in their doctor’s office; others may go to the hospital. A chemotherapy regimen (schedule) usually consists of a specific number of cycles given over a specific time.

Chemotherapy for anal cancer usually consists of a combination of drugs. The main chemotherapy drugs given for anal cancer are fluorouracil (5-FU, Adrucil) and mitomycin C (Mitozytrex, Mutamycin), or fluorouracil and cisplatin (Platinol). It is particularly valuable for treating anal cancer when given in combination with radiation therapy. The combined treatment allows the use of lower radiation doses and improves the likelihood of completely destroying the tumor. Patients with both anal cancer and HIV may receive lower doses of chemotherapy.

The side effects of chemotherapy depend on the individual and the dose used, but can include fatigue, risk of infection, nausea and vomiting, loss of appetite, and diarrhea. These side effects usually go away once treatment is finished.

Learn more about preparing for treatment. 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. Learn more about your prescriptions by using searchable drug databases.

Recurrent anal cancer

The treatment of recurrent anal cancer depends on the original treatment. For example, a patient who initially had chemotherapy and radiation therapy may be treated with surgery if the cancer recurs.

Find out more about common terms used during cancer treatment.