Tests and diagnosis

By Mayo Clinic Staff

To make the diagnosis, your doctor will likely:

  • Ask about your medical history, and your family's medical history.
  • Perform a complete physical exam.
  • Order an imaging test. Imaging tests, such as X-rays, computerized tomography (CT) scans, ultrasound, magnetic resonance imaging (MRI) and positron emission tomography (PET), also may be done to enable your doctor to see and evaluate the area of concern.
  • Remove a sample of tissue (biopsy).

Techniques for biopsy of a suspected soft tissue sarcoma include:

  • Needle biopsy. Your doctor uses a thin needle to remove small pieces of tissue from the tumor. There are two types of needle biopsy — fine-needle aspiration and core biopsy. A core biopsy involves using a slightly larger needle to remove a small, solid core of tissue, and it's the preferred method of biopsy for soft tissue sarcomas. If a soft tissue sarcoma is suspected, it's important to have a doctor who is familiar with the treatment of these cancers perform the biopsy. A biopsy needs to be carefully planned, as it can alter the surgical management of a soft tissue sarcoma.
  • Surgical biopsy. Your doctor makes an incision through your skin and removes either the entire tumor (excisional biopsy) or a portion of the tumor (incisional biopsy). In some cases you may need only local anesthesia. For a larger or deep-seated tumor, you'll likely require general anesthesia during the procedure. This type of biopsy is much less likely to be used because it has a higher rate of complications. Because surgical biopsies aren't done as frequently, it's important that a doctor experienced in the treatment of sarcomas perform this type of biopsy.

Grading and staging

Besides determining whether it is malignant, examining tissue can determine how aggressive the cancer is (its grade). Further testing, such as with imaging scans and blood tests, can help determine if the cancer has spread and, if so, how far (its stage).

  • Stage I. These tumors are generally small, but what's important is that the tumor cells appear normal. Additionally, the sarcoma hasn't spread to the lymph nodes or to distant sites.
  • Stage II. In more advanced soft tissue sarcomas, the cells begin to look more abnormal. At this stage, however, it still hasn't spread to the lymph nodes or other areas of the body.
  • Stage III. Not only do the cells look even more abnormal, but malignant cells are found in one or more lymph nodes.
  • Stage IV. At this stage, the cells look severely abnormal, and the cancer can be found in the lymph nodes and in other parts of the body.
Sep. 13, 2011