Kidney cancer is one of the 10 most common cancers for men and women – more than 75,000 people are diagnosed each year. Most kidney cancer is detected at an early stage before symptoms start. But 20% to 30% of the time, it presents with symptoms and is diagnosed at a more advanced stage.
The majority of kidney tumors are discovered accidentally, according to Brian Shuch, MD, director of the Kidney Cancer Program at UCLA Health. “People go for imaging for some other cause and are found to have a kidney tumor,” he says. “But we also see later-stage diagnoses that present symptomatically.”
Signs of kidney cancer
The same symptoms that suggest kidney cancer can also signal a variety of other conditions. But if symptoms indicate a tumor, the sooner you can get treatment, the better. The survival rate for kidney cancer drops significantly at advanced stages.
“Many patients who present symptomatically have locally advanced cancer with a large bulky tumor,” Dr. Shuch says. “The cancer may be invasive or metastatic (spread to other organs).”
Kidney cancer symptoms may include:
Blood in the urine (hematuria)
Men and women often dismiss blood in the toilet, especially if they only see it occasionally. Dr. Shuch advises that anytime you see blood in the toilet, it is a cause for some concern. It could be the result of vaginal bleeding, hemorrhoids or a number of other problems. But when the blood is in your urine stream, the issue may be serious.
“Blood in your urine stream should always be checked out – it could be coming from anywhere in your urinary tract including the kidneys, ureters, bladder, prostate or urethra,” Dr. Shuch says. “The cause of the blood could range from something that’s not dangerous and is easily correctable to a potentially life-threatening issue where a delay in diagnosis and treatment could have serious consequences.”
Flank pain
Flank pain is discomfort in your upper abdomen or back and sides. It may occur when your kidneys are inflamed or from a growing tumor.
The problem is that many people dismiss lower back pain as a pulled muscle or a side effect of aging. But if your pain is persistent and doesn’t respond to normal conservative measures (such as massage, heating pad, stretching, weight loss or physical therapy), you need to see a doctor and look for other causes.
“Flank pain is different from abdominal pain or general back pain. It’s on one side and deeper inside, underneath the rib cage,” Dr. Shuch says. There are plenty of conditions that can cause pain in that area, but they usually require a deeper evaluation than just a physical exam and labs. “When conservative measures don’t eliminate the pain, then urinalysis, blood tests, ultrasound or a CT (computed tomography) scan can be useful in determining the cause of the pain.”
Abdominal mass
If your kidney is enlarged or has a growth, it could cause a mass or bulge on the side of your abdomen. In the earlier stages, your doctor may notice a kidney lump during a routine examination before you notice it yourself.
When kidney cancer is advanced, you may feel an actual protrusion or an unusually firm and thickened area. Remember, not all masses are cancer. But if you feel a lump in your abdomen, you should consult your provider.
Paraneoplastic syndromes
These rare disorders occur when the immune system responds to a cancerous tumor in an abnormal way or the tumor secretes substances that have actions throughout the body. Often the symptoms of a paraneoplastic syndrome are the first sign of cancer and can potentially be more harmful than kidney cancer.
Symptoms of these syndromes vary but may include:
- Fever
- Loss of appetite
- High calcium
- Increased or decreased blood cell or platelet count, shown on a blood test
If your provider recognizes these symptoms, you should have more tests. Paraneoplastic syndromes develop in approximately 20% of people who have cancer and may help diagnose cancer at an earlier stage.
Symptoms of metastatic kidney cancer
Kidney cancer can metastasize (spread) to any part of the body through the blood or lymphatic system. When that happens, the first signs of cancer may not be specific to your kidneys.
Instead, metastatic kidney cancer may cause symptoms in the newly affected areas of the body including:
- Lungs, causing cough and shortness of breath
- Bones, resulting in bone pain or fracture
- Brain, presenting as headaches, confusion or seizures
Know your risk for kidney cancer
Since kidney cancer only has a lifetime risk of 1% in women and 2% in men, providers do not generally screen people for it. But there are certain factors that can put you at higher risk, including:
- Chronic kidney disease
- Family history of kidney cancer
- High blood pressure (hypertension)
- Obesity
- Smoking
If you have several family members diagnosed with kidney cancer, Dr. Shuch recommends considering genetic counseling to assess your risk. “Hereditary forms of kidney cancer are rare but there is increasing recognition that many patients with kidney cancer may have some degree of a genetic predisposition,” he says. “You may be predisposed if your family’s health history reveals early age of onset or multiple kidney tumors (in one or both kidneys) or any other concerning association with cancers in addition to kidney cancer.”
If you have any symptoms associated with kidney cancer, talk to your primary care provider.
