Understanding Your Grade and Stage of Soft Tissue Sarcoma

A pathologist is a specialized doctor who looks at tissue samples under a microscope to determine whether they are cancerous or not. These are the samples removed during a biopsy. If your doctor suspects a sarcoma, it is important to be sure that a pathologist who is an expert in sarcoma pathology reviews your tissue as well. Since there are not that many expert pathologists in the United States who specialize in sarcoma pathology, you may need to request a specialized pathology review.

Pathologists determine the specific type of sarcoma you have. They also determine the grade of your tumor. The grade tells your doctor how your cancer may behave or how likely it is to spread to other parts of the body. A low-grade tumor closely resembles normal cells. A high-grade tumor may spread more readily to other parts of the body. High-grade soft tissue sarcomas that start in your arms or legs can spread to your lungs. High-grade soft tissue sarcomas that start inside your abdomen can spread to your liver.

In addition to your tumor’s grade, doctors need to determine the stage of your sarcoma. The staging system takes into account the size of your original tumor and whether the tumor has spread to other parts of your body. The size of a soft tissue sarcoma is important, but unlike most cancers, it is not as important as what the cancer cells look like under a microscope (their grade). The more abnormal the cancer cells appear, the higher the stage and grade.

These are the American Joint Committee on Cancer (AJCC) stages for soft tissue sarcoma.

• Stage IA. The cancer cells appear slightly abnormal. The cells look most like the cells where they came from. The cancer is low-grade, small, and superficial or deep. It has not spread to the lymph nodes or other parts of the body.

• Stage IB. The cancer cells appear slightly abnormal. The cancer is low-grade, large, and superficial. It has not spread to other parts of the body.

• Stage IIA. The cancer cells appear abnormal. The cancer is low-grade, large, and deep inside the body. It has not spread to other parts of the body.

• Stage IIB. The cancer cells appear abnormal. The cancer is high-grade, small, superficial, and deep. It has not spread to other parts of the body.

• Stage IIC. The cancer cells appear abnormal. The cancer is high-grade, large, and superficial. It has not spread to other parts of the body.

• Stage III. The cancer cells appear very abnormal. The cancer is high-grade, large, and deep. It has not spread to other parts of the body.

• Stage IV. The cancer has spread to the lymph nodes and other parts of the body, such as the lungs or liver.