Some possible symptoms of kidney cancer include bloody urine, loss of appetite, pain at the side of the body and weight loss, according to WebMD. A fever with no other known cause can be a sign of kidney cancer, as can anemia and extreme fatigue. People with kidney cancer might also have swelling in their legs or ankles.
In its early stages, kidney cancer might not cause any symptoms in patients. A doctor can diagnose kidney cancer by finding a lump on a kidney during a routine physical examination, notes WebMD. Signs that a patient has kidney cancer might also arise as the doctor evaluates tests for other conditions. Kidney cancer spreads to other parts of the body over time, leading to other symptoms. Some of these symptoms include bone pain, shortness of breath and coughing up blood.
A doctor typically makes a diagnosis of kidney cancer after running several tests, explains WebMD. Urine tests help doctors look for blood or other signs of kidney cancer, and blood tests can reveal how well a patient's kidneys function. Imaging plays a role as well; CT scans create images of the kidneys, and MRIs provide detailed images of soft tissue. Doctors might also rely on the results of renal arteriograms.