Synovial Sarcoma: Questions and Answers ( 6/29/05) NCI has updated Synovial Sarcoma: Questions and Answers. Synovial sarcoma is a type of soft tissue sarcoma. Soft tissue sarcomas are cancer of the muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body, including synovial tissue. Synovial tissue lines the cavities of joints, such as the knee or elbow, tendons (tissues that connect muscle to bone), and bursae (fluid-filled, cushioning sacs in the spaces between tendons, ligaments, and bones). Although synovial sarcoma does not have a clearly defined cause, genetic factors are believed to influence the development of this disease. To view: http://cis.nci.nih.gov/fact/6_1.htm LINK to NCI information Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.