The first sign of a sarcoma in an arm, leg, or torso may be a painless lump or swelling. Most lumps are not sarcoma. The most common soft-tissue lumps are lipomas. Lipomas are made of fat cells and are not cancer. Lipomas have often been there for many years and rarely change in size. In the uterus, benign tumors called fibroids, or leiomyomas …

https://www.cancer.net/cancer-types/sarcoma-soft-tissue/symptoms-and-signs