Overview About half of soft tissue tumors start in the arms or legs, and the other half are found in the torso, or trunk area. Understanding Your Diagnosis Symptoms of soft tissue sarcoma include a painless lump on the body, stomach pain or vomiting, and a lack of appetite or weight loss. These can be symptoms of other conditions as well, so it's important to see your doctor for a diagnosis. Deciding on Treatment Your treatment plan depends on your age and health, and the extent of the disease. You may need surgery, chemotherapy, radiation therapy, or a combination of these. Managing Side Effects Side effects are common during treatment for cancer, and they vary from person to person. Your health care team will work to ease any side effects you experience.