The majority of sarcomas develop in people with no known risk factors, and there is currently no known way to prevent these cases. Whereas future developments in genomic research may allow genetic testing to identify persons with increased risk of developing soft tissue sarcomas, few such predictors are available at present. Reporting suspicious lumps and growths or unusual symptoms to a doctor, and appropriate evaluation of such abnormalities can help diagnose soft tissue cancer at an earlier stage. Treatment is thought to be more effective when detected early, as smaller-diameter sarcomas have been shown to have improved outcome compared to large sarcomas.

Whenever physicians examine a patient presenting with a new mass in the leg, thigh, muscles, and deep tissue of the body, particularly if the patient has a previous history of cancer, metastatic cancers in the soft tissues should be considered. The most likely cancers to metastasize to soft tissue are cancers of the lung and kidney.