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 this happens, it is called metastasis. For example, imaging tests can show if the cancer has spread. Imaging tests show pictures of the inside of the body. 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 if 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 HIV/AIDS-related cancer is diagnosed

There are many tests used for diagnosing an HIV/AIDS-related 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

• The results of earlier medical tests

The following tests may be used to diagnose an HIV/AIDS-related cancer or to determine if or where it has spread:

• Biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope. Other tests can suggest that cancer is present, but only a biopsy can make a definite diagnosis. A pathologist then analyzes the sample(s). A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease.

• 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 is usually injected into a patient’s vein. CT scans of the chest and abdomen can help find cancer that has spread to the lungs, lymph nodes, or liver.

• X-ray. An x-ray is a way to create a picture of the structures inside of the body, using a small amount of radiation.

• Endoscopy. An endoscopy allows the doctor to see the inside the body with a thin, lighted, flexible tube called an endoscope. The person may be sedated as the tube is inserted through the mouth, down the esophagus, and into the stomach and small bowel. Sedation is giving medication so the patient becomes more relaxed, calm, or sleepy. If abnormal areas are found, the doctor can remove a sample of tissue and check it for cancer. The doctor can examine the large intestine with a specific endoscopic procedure called a colonoscopy.

Kaposi sarcoma

• Bronchoscopy. Similar to an endoscopy, the doctor passes a thin, flexible tube with a light on the end into the mouth or nose, down through the windpipe, and into the breathing passages of the lungs. This procedure may be performed by a surgeon or a pulmonologist. A pulmonologist is a medical doctor who specializes in lung diseases. The tube lets the doctor see inside the lungs. Tiny tools inside the tube can gather samples of fluid and tissue and remove them for examination by a pathologist. Patients are given mild anesthesia during a bronchoscopy. Anesthesia is medication to block the awareness of pain.

• Photography. Because many skin lesions can develop in different parts of the body, doctors may regularly photograph parts of the skin. This is called mapping. It is done to find out if new lesions have developed over time.

Non-Hodgkin lymphoma

• Positron emission tomography (PET) or PET-CT scan. 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 PET scan is a way to create pictures of organs and tissues inside the body. 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. A nuclear medicine physician interprets the scan.

  A doctor can use this technique to look at both the structure and how much energy is used by the tumor and healthy tissues. If, after having 1 or more imaging tests, the doctor decides the lymphoma might be affecting the bone marrow, they may recommend a bone marrow biopsy.

• Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can also be used to measure the tumor’s size. A special dye called 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 to swallow. A radiologist interprets the scan.

• Bone marrow aspiration and biopsy. These 2 procedures are similar and typically done at the same time to examine the bone marrow. Bone marrow has both a solid and a liquid part. A bone marrow aspiration removes a sample of the fluid with a needle. A bone marrow biopsy is the removal of a small core of solid tissue using a needle.

  A pathologist or hematopathologist then analyzes the sample(s). A hematopathologist is a pathologist with specialized training in lymphoma, leukemia, and other blood cancers. A common site for a bone marrow aspiration and biopsy is the pelvic bone, which is located in the lower back by the hip. Doctors generally give a type of medication called "anesthesia" beforehand to numb the area. Anesthesia is medication that blocks the awareness of pain. Stronger types of anesthesia can also be used to lessen the pain. The patient may also receive other types of anesthesia to block the awareness of pain.

  Lymphoma often spreads to the bone marrow, so looking at a sample of the bone marrow can be important for diagnosing lymphoma and determining the stage. The doctor can also use the sample removed during the aspiration to find any chromosome changes.

• Lumbar puncture (spinal tap). Some aggressive lymphomas, especially Burkitt lymphoma, carry a risk of entering the spinal fluid surrounding the brain and spinal cord (central nervous system) or going to the brain tissue itself. As a result, a diagnostic lumbar puncture may be used in the initial staging. Brain imaging, usually an MRI (see above), may also be used. A lumbar puncture is a procedure in which a needle is used to take a sample of cerebral spinal fluid to look for cancer cells, blood, or tumor markers. Doctors generally give an anesthetic to numb the lower back before the procedure. Chemotherapy may be used to treat or prevent cancer spread to the central nervous system.

• Biomarker testing of the tumor. Your doctor may recommend running laboratory tests on a tumor sample and/or bone marrow sample to identify specific genes, proteins, and other factors unique to the disease. This may also be called molecular testing of the tumor. Results of these tests can help determine your treatment options. There are different types of molecular and genetic testing:

• Cytogenetics studies healthy and abnormal chromosomes in dividing cancer cells.

• Fluorescent in situ hybridization (FISH) uses fluorescent probes under a special microscope to detect changes in specific chromosomes.

• Flow cytometry looks at proteins that are on the surface or inside a cancer cell.

• Polymerase chain reaction (PCR) finds specific DNA sequences that occur in some cancers.

• Extended molecular profiling is used to broadly review tumor markers or to find very small amounts of remaining cancer after treatment finishes. Although this is still being studied, it may become more commonly used in the near future.

Cervical cancer

• Bimanual pelvic examination and sterile speculum examination. In this examination, the doctor will check for any unusual changes in the patient's cervix, uterus, vagina, ovaries, and other nearby organs. To start, the doctor will look for any changes to the vulva outside the body and then, using an instrument called a speculum to keep the vaginal walls open, the doctor will look inside the vagina to visualize the cervix. A Pap test is often done at the same time. Some of the nearby organs are not visible during this exam, so the doctor will insert 2 fingers of 1 hand inside the vagina while the other hand gently presses on the lower abdomen to feel the uterus and ovaries. This exam typically takes a few minutes and is done in an examination room at the doctor’s office.

• Pap test. During a Pap test, the doctor gently scrapes the outside and inside of the cervix, taking samples of cells for testing.
  
  Improved Pap test methods have made it easier for doctors to find cancerous cells. Traditional Pap tests can be hard to read because cells can be dried out, covered with mucus or blood, or may clump together on the slide.

• The liquid-based cytology test, often referred to as ThinPrep or SurePath, transfers a thin layer of cells onto a slide after removing blood or mucus from the sample. The sample is preserved so other tests can be done at the same time, such as the HPV test (see Screening and Prevention).

• Computer screening, often called AutoPap or FocalPoint, uses a computer to scan the sample for abnormal cells.

• HPV typing test. An HPV test is similar to a Pap test. The test is done on a sample of cells from the cervix. The doctor may test for HPV at the same time as a Pap test or after Pap test results show abnormal changes to the cervix. Certain types or strains of HPV, called high-risk HPV, such as HPV16 and HPV18, are seen more often in women with cervical cancer and may help confirm a diagnosis. If the doctor says the HPV test is “positive,” this means the test found the presence of high-risk HPV. It is possible to have HPV but not cervical cancer, so HPV testing alone is not enough for a diagnosis of cervical cancer.

• Colposcopy. The doctor may do a colposcopy to check the cervix for abnormal areas. Colposcopy can also be used to help guide a biopsy of the cervix. During a colposcopy, a special instrument called a colposcope is used. The colposcope magnifies the cells of the cervix and vagina, similar to a microscope. It gives the doctor a lighted, magnified view of the tissues of the vagina and the cervix. The colposcope is not inserted into the body, and the examination is similar to a speculum examination. It can be done in the doctor's office and has no side effects. It can also be done during pregnancy.

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 an HIV/AIDS-related cancer. Use the menu to choose a different section to read in this guide.