The majority of sarcomas develop in people with no known risk factors: There is currently no known way to prevent these cases at this time. Whereas future developments in genomic research may allow genetic testing to identify persons with increased risk to develop 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.

Cancers occasionally spread or metastasize to the soft tissues, such as the muscles and deep tissues of the body, including the thigh and leg. The most likely cancers to do so are cancers of the lung and kidney. As such, this fact must always be borne in mind whenever physicians examine a patient presenting with a new mass in the leg, thigh, or other soft tissues, especially if they have a history of a prior lung or kidney cancer.