Signs of kidney cancer include bloody urine, unexplained low back pain on one side, unexplained weight loss, or a lump on the side or lower back, states the American Cancer Society. Other symptoms are tiredness, appetite loss, unexplained prolonged fever and anemia. However, all of these usually have noncancerous causes.
When kidney cancer is in its early stages, it typically does not exhibit symptoms, according to the American Cancer Society. Most kidney cancers are first treated surgically, Mayo Clinic explains. Sometimes just the tumor is taken out, but in certain cases, the entire kidney is removed. If surgery is not possible, kidney tumors are frozen with a gas introduced through a needle, or cancer cells are burned with electrical current.