Soft tissue sarcomas are cancers that can occur anywhere in the body. They arise from striated muscle in the arms and legs (rhabdomyosarcoma); blood vessels (angiosarcoma, hemangiosarcoma and Kaposi's sarcoma); fibrous connective tissue (fibrosarcoma); smooth muscle (leiomyosarcoma); fat cells (liposarcoma); lymph vessels (lymphangiosarcoma); nerve fiber sheaths (neurilemoma); and membranes around the joints and tendons (synovial sarcoma).

There will be approximately 8,100 cases diagnosed this year in the United States, or one percent of all adult cancers. Many of these tumors develop in the arms and legs.

The causes of sarcoma may include a genetic component, radiation exposure, lymphedema or chemical exposure. They generally develop as a mass which may or may not be painful depending on its location in the body.

Any suspicious growth, particularly one that is growing, should be brought to the attention of a physician. This photo is an example of a sarcoma developing on an arm.