Sarcoma is a rare type of cancer that affects the connective tissues of the body, such as muscle, bone, fat, cartilage, and blood vessels. Common symptoms of sarcoma include a lump or swelling in an arm or leg, unexplained pain, fatigue, difficulty breathing, and a fever that does not go away. More specific symptoms depend on the location of the tumor. For example, a tumor in an arm or leg may cause a weakened limb, while a tumor in the abdomen may cause a feeling of fullness or abdominal pain. Other symptoms may include nausea, vomiting, weight loss, and a noticeable lump in the affected area. If you experience any of these symptoms, it is important to consult your doctor.