Kidney cancer symptoms

Kidney cancer is often difficult to detect in its early stages. In fact, before a tumor has grown or the disease has spread, kidney cancer is most commonly caught when it’s discovered by an X-ray or ultrasound performed for another reason.

Many factors contribute to this delayed diagnosis, including the location of the kidneys—deep inside the body, where small tumors are less likely to be seen or felt during a physical exam. Once the disease has grown or advanced beyond the kidneys—generally to nearby lymph nodes or to the lungs, bones or liver—signs are more likely to develop, but they are often mistaken for less serious conditions.

Early warning signs of kidney cancer

The most common sign of kidney cancer is blood in the urine (hematuria), which may make the urine look rusty or dark red. Other signs of kidney cancer may include: 

• Low back pain or pressure on one side that doesn’t go away
• A mass or lump on the side or lower back
• Fatigue
• Loss of appetite or unexplained weight loss
• A persistent fever not caused by infection
• Anemia (low red blood cell count)
• Swelling of the ankles and legs
• In men, a cluster of enlarged veins, called a varicocele, around a testicle, typically, the right testicle

Although these symptoms may indicate a kidney tumor, they also may be caused by other, less serious health issues. Some kidney cancer patients experience none of these signs, and others experience different symptoms entirely.

Learn more about Kidney cancer treatments

Next topic: What are the types of kidney cancer?