Sarcomas of Specific Organs: Diagnosis

Approved by the Cancer.Net Editorial Board, 07/2016

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. To see other pages, use the menu.

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 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.

This list describes options for diagnosing this type of cancer. Not all tests listed below 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 medical condition

  • The results of earlier medical tests

In addition to a physical examination, the following tests may be used to diagnose all types of STS:

  • 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. A biopsy is the most definitive test for diagnosing sarcoma.

  • 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 3-dimensional picture of the inside of the body using x-rays taken from different angles. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. CT scans can also be used to guide a needle biopsy, in which a very thin needle is inserted into the suspicious area and a sample of cells is gathered for examination under a microscope. A CT scan can also 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 liquid to swallow.

  • 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 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 liquid to swallow.

The following tests may also be used to diagnose a specific type of STS, depending on the parts of the body affected and other factors:

  • Bone scan. A bone scan uses a radioactive tracer to look at the inside of the bones. The tracer is injected into a patient’s vein. It collects in areas of the bone and is detected by a special camera. Healthy bone appears gray to the camera, and areas of injury, such as those caused by cancer, appear dark.

  • Blood tests. A complete blood count (CBC) may be done to measure the different types of blood cells.

  • Heart evaluation. A heart evaluation, including an electrocardiogram (EKG or ECG) and an echocardiogram (ECHO), will look for structural abnormalities in the organ and motion of the walls of the heart. This evaluation is used to diagnose cardiac sarcoma.

  • Coronary arteriogram. A coronary arteriogram highlights any abnormalities of the arteries. A dye is injected into an artery and then an x-ray is taken.

  • Mammography. A mammogram is a type of x-ray that looks for any abnormalities or tumors in the breast. This imaging test may be used with MRI scans, CT scans, and a biopsy to diagnose a sarcoma in the breast. 

After diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is sarcoma, these results also help the doctor describe it. This is called staging and grading.

The next section in this guide is Stages and Grades. It explains the system doctors use to describe the extent of the disease. Or, use the menu to choose another section to continue reading this guide.