Undifferentiated pleomorphic sarcoma symptoms depend on where the cancer occurs. It most often happens in the arms and legs, but it can happen anywhere in the body. Signs and symptoms may include: 
Growing lump or area of swelling
If it grows very large, there may be pain, tingling and numbness
If it occurs in an arm or leg, there may be swelling in the hand or foot of an affected limb
If it occurs in the abdomen, there may be pain, loss of appetite and constipation
Fever
Weight loss
