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Doctors use many tests to diagnose cancer and find out if it has metastasized (spread). Some tests may also determine which treatments may be the most effective. For most types of cancer, a biopsy is the only way to make a definitive diagnosis of cancer. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Imaging tests may be used to find out whether the cancer has metastasized. Your doctor may consider these factors when choosing a diagnostic test:
- Age and medical condition
- Type of cancer suspected
- Severity of symptoms
- Previous test results
In addition to a physical examination, the following tests 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. The sample removed from the biopsy is analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease).
To determine if Kaposi sarcoma has spread to internal organs, the doctor may perform the following examinations:
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 creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium (a special dye) is injected into a patient's vein to provide better detail. CT scans of the chest and abdomen can help find cancer that has spread to the lungs, lymph nodes, or liver.
Endoscopy. This test 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.
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 medical doctor who specializes in lung problems). The tube lets the doctor see inside the lungs. Tiny tools inside the tube can gather samples of fluid and tissue and remove them, so the pathologist can examine the samples. Patients are given mild anesthesia (medication to block the awareness of pain) during a bronchoscopy.
Photography. Because many skin lesions can develop in different parts of the body, doctors may regularly photograph parts of the skin (called mapping) to find out if new lesions have developed over time.
Learn more about what to expect when having common tests, procedures, and scans.
After these diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is cancer, these results also help the doctor describe the cancer; this is called staging. Learn more about the first steps to take after a diagnosis of cancer.