Overview

Soft tissue sarcoma is cancer that develops in the tissues that support and connect the body. A sarcoma can occur in fat, muscle, nerves, tendons, joints, blood vessels, or lymph vessels. A sarcoma begins when a cell grows out of control, and instead of developing (called differentiating) into a normal cell, it forms a lump (tumor). When a sarcoma is small, it may go unnoticed or be ignored, since it does not usually cause problems at this stage. Most patients with smaller soft tissue sarcomas can be treated successfully. However, if it grows, it can interfere with the body's normal activities; it can also spread to other places in the body. This makes it more challenging to treat successfully.

Sarcoma can appear in any part of the body. About 50% occur in the arms or legs, 40% occur in the trunk or abdomen, and 10% occur in the head or neck. Sarcoma is rare, accounting for about 1% of all cancers.

Because there are several different types of soft tissue sarcoma, it is probably best considered as a family of related diseases, rather than a single, specific disease. Two types of sarcoma, alveolar soft part sarcoma (ASPS) and cardiac sarcoma, are discussed in this section. For more information on other types of sarcoma, read the Guide to Sarcoma.

ASPS is a slow-growing tumor that usually occurs in the thigh or leg, but sometimes on the head or neck.

Tumors of the heart are uncommon, and most heart tumors are benign (non-cancerous). However, cardiac sarcoma is a rare cancer that occurs in or on the heart. This type of tumor is almost always malignant (cancerous). Most frequently, this tumor type is an angiosarcoma, which often begins in one of the chambers of the heart or within the muscle tissue of the heart. About 25% of angiosarcoma cases occur inside the heart; this can obstruct the flow of blood and cause symptoms.

Statistics

In 2009, approximately 10,660 new cases (5,780 men and 4,880 women) of soft tissue sarcoma are expected to be diagnosed in the United States. An estimated 3,820 adults and children (1,960 males and 1,860 females) are expected to die of the disease this year. ASPS and cardiac sarcoma each make up less than 1% of sarcoma cases.

Cancer statistics should be interpreted with caution. These estimates are based on data from thousands of cases of this type of cancer, but the actual risk for a particular individual may differ. It is not possible to tell a person how long he or she will live with ASPS or cardiac sarcoma.

Statistics adapted from the American Cancer Society's publication, Cancer Facts and Figures 2009.

Find out more about basic cancer terms used in this section.