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 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 Kaposi sarcoma is diagnosed

There are many tests used for diagnosing Kaposi sarcoma. 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

In addition to a physical examination, a biopsy may be used to diagnose Kaposi sarcoma:

• 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.

To find out if Kaposi sarcoma has spread to internal organs, any of the following examinations may be performed:

• 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.

• 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.

• Endoscopy. An endoscopy allows the doctor to see 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 to become more relaxed, calm, or sleepy.

• 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 take pictures of parts of the skin. This is called mapping. It is done to find out if new lesions have developed over time.

After diagnostic tests are done, your doctor will review the results with you. If the diagnosis is Kaposi sarcoma, 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.