Your soft tissues connect, support or surround other tissues. Examples include your muscles, tendons, fat and blood vessels. Soft tissue sarcoma is a cancer of these soft tissues. There are many kinds, based on the type of tissue they started in. Sometimes they spread and can press on nerves and organs, causing problems such as pain or trouble breathing.

No one knows exactly what causes these cancers. They are not common, but you have a higher risk if you have been exposed to certain chemicals, had radiation therapy or have certain genetic diseases.

To diagnose soft tissue sarcomas, doctors must remove and look at piece of the tumor under a microscope. Treatments include surgery to remove the tumor, radiation therapy, chemotherapy or a combination.