What is kidney cancer?
Kidney cancer is a disease where cancer cells begin to develop abnormally in the kidneys. As cancer cells grow rapidly, they can form a tumor, and eventually, the cancer can spread to other parts of the body.
The main types of kidney cancer are:
— Renal cell carcinoma, the most common type, accounting for 90% of kidney cancers, according to the American Cancer Society
— Transitional cell carcinoma
— Wilms tumors (nephroblastomas), most commonly found in children
— Renal sarcoma
Kidney cancer is one of the 10 most common cancers in the United States, with an estimated nearly 700,000 people living with kidney and renal pelvis cancer, reports the ACS and the National Cancer Institute’s Surveillance, Epidemiology and End Results Program (SEER). The five-year relative survival rate for kidney and renal pelvis cancers is 78.6%, according to 2020 SEER data.
Kidney cancer is notable for not always causing early, obvious symptoms. Most kidney cancers are found incidentally, meaning they are found by chance during tests and imaging for other health concerns.
Read on to learn more about the stages of kidney cancer symptoms, from early to advanced.
No symptoms
Kidney cancers, especially when small, often don’t cause any symptoms. Kidney cancer symptoms can also be delayed because the kidney’s central, internal location is often surrounded by fat, says Dr. Mia Kazanjian, a board-certified radiologist and director of women’s imaging at Norwalk Radiology Consultants with Stamford Health
“This gives kidney cancer cover, time and space to grow until it is large enough to cause pressure on the kidney’s collection system or other organs,” she explains.
So, why don’t we routinely screen for kidney cancers, the same way we screen for breast and prostate cancer? There is not a single, low-risk, cost-effective screening test comparable to something like a mammogram for breast cancer, Kazanjian says. Instead, she recommends speaking with your doctor if you have a family history of kidney cancer or heritable conditions like tuberous sclerosis, Birt-Hogg-Dubé or von Hippel-Lindau disease, which would be a reason for regular proactive screening.
If you had an incidental kidney mass found on a CT scan, the next steps would potentially include additional imaging or a biopsy. Your doctor will talk to you about whether it is most appropriate to do active surveillance, where you monitor the tumor for growth over a period of time, or whether surgery or ablation (using extreme temperatures to destroy tumors) is a better treatment option.
Hematuria
Even though asymptomatic kidney cancer is the most common, there is a “classic triad” of kidney cancer symptoms, which includes:
— Hematuria
— An abdominal mass
— Flank pain
This classic symptom triad is rare with today’s contemporary imaging, says Dr. John Phillips, a professor and chair of urology at New York Medical College in Valhalla, New York. This is because the vast majority of patients’ kidney cancer is found by chance on a CT or MRI study obtained for other purposes.
“It is often said that patients present with the classic triad about 10% of the time, but it is probably more like 1% of the time,” Phillips notes.
One of the symptoms in the classic triad is hematuria, or blood in the urine. In cases where the blood is visible to the naked eye, the urine may be red, pink or cola-colored. Other times, the blood is only noticed when picked up by a lab test called a urinalysis.
Abdominal mass
Another symptom in the classic triad of kidney cancer symptoms is a lump or mass in the side of the abdomen. This may feel like fullness, firmness or a visible bulge. Masses may be benign (noncancerous) or malignant (cancerous). “Localized” growths are confined to the kidney. “Metastatic” kidney masses have spread to other parts of the body. Kidney tumors can be solid or cystic, meaning they contain fluid.
While not everyone will notice a mass, finding a new or unusual lump in your abdomen or side should always prompt you to make an appointment with your doctor. During a physical examination, a doctor often feels or palpates your abdomen to detect abnormalities. He or she may feel a growth in your abdominal area. That could possibly be a renal or kidney mass, or tumor.
Flank pain
The last remaining symptom in the classic triad of kidney cancer symptoms is flank pain not caused by an injury. Persistent flank pain on one side that doesn’t go away may be a sign of kidney cancer.
Where exactly is kidney cancer pain felt in the back? The right and left flanks are the parts of your side torso between your ribs and each hip. Kidney pain occurs higher in the back than typical low back pain and is deeper. You might feel this pain under your ribs, to the side of your spine. Pain can range from sharp and stabbing to just a mild ache or a feeling of pressure that doesn’t go away.
If you do have symptoms of a renal tumor — either with flank pain, an abdominal mass or hematuria — then it usually means you have an advanced or aggressive tumor that may have a poorer prognosis, says Dr. Gautam Jayram, a urologist and member of the Large Urology Group Practice Association in Nashville, Tennessee.
Unexplained weight loss
Losing weight without intending to can be a symptom of several types of cancer, including kidney cancer. This symptom happens because cancer changes how your body uses energy, which affects your appetite and metabolism.
Similarly, a decrease in appetite for no obvious cause is also a general symptom for cancer. Let your doctor know about sudden weight or appetite loss, so it can be evaluated using your medical history and diagnostic testing, if indicated.
Chronic fatigue
Fatigue can be caused by kidney cancer or some of its treatments. What does kidney cancer fatigue feel like compared to normal tiredness? It’s a deeper exhaustion that doesn’t improve as much after sleep or rest.
Fatigue in kidney cancer can also feel like the following:
— Lack of interest in your usual activities
— Overall weakness
— Feeling of heaviness
— Memory, concentration, attention or thinking problems
— Decreased ability to perform daily tasks
Persistent fever or night sweats
Persistent fever or night sweats are other potential signs of kidney cancer.
When fever or night sweats linger without an obvious cause, like a current cold or flu infection, it can be a sign that your immune system is responding to something serious. On its own, it might not be cancer, but it is worth investigating with your medical provider.
Anemia
Anemia means you don’t have enough healthy red blood cells to carry oxygen through your body.
Anemia can cause:
— Weakness
— Dizziness
— Shortness of breath
— Looking more pale than usual
Kidney cancer interferes with normal blood production, leading to anemia over time. If blood tests show low red blood cell counts, that means you have anemia.
High blood pressure and swelling
Why are swollen ankles and high blood pressure symptoms of kidney cancer?
The kidneys play a major role in regulating blood pressure and fluid balance. When cancer interferes with this part of kidney function, blood pressure can rise, and you may notice swelling in your legs, ankles or sometimes in your face.
New or worsening high blood pressure, especially when paired with other symptoms, like swelling, can be a clue that the kidneys are not functioning properly.
Symptoms that look like something else
Many kidney cancer symptoms look like something else or are shared with more benign conditions, such as:
— Back strain
— Hormonal changes
Symptoms mimicking other conditions is one of the reasons a kidney cancer diagnosis can get delayed. If you have a symptom that keeps coming back, doesn’t respond to treatment or you feel uneasy about, ask your doctor if they think something more serious could be going on.
Shortness of breath
Shortness of breath, or difficulty breathing, is a more advanced symptom of kidney cancer that has likely spread.
“Advanced Stage 3 or Stage 4 cancers are different and thankfully very uncommon,” Phillips says.
Metastasis, when the cancer spreads, is the true cause of disability and pain and tends to involve organs like the lungs, which can cause shortness of breath, Phillips adds.
Bone pain
Bone pain is another advanced symptom of metastasized kidney cancer that has spread to the bones when it is not linked to another injury.
It can be painful but treatable, Phillips says.
Persistent cough
A persistent cough can be another sign of advanced kidney cancer, signaling that the cancer has traveled to the lungs. The cough might be dry or accompanied by chest discomfort.
Coughs are common in other diseases, such as bronchitis or pneumonia, so they are not always indicative of kidney cancer. If you have a cough that lingers for a few weeks, make sure to talk to your doctor. Even if it is not kidney cancer, it’s worth getting checked out.
Symptoms in men
Kidney cancer is about twice as common in men, and men typically present with larger masses, Kazanjian says.
One distinct symptom men may have is a varicocele, which is testicular venous swelling.
“This is because if a mass is large enough, it can compress the left renal vein and cause the spermatic vein to dilate,” Kazanjian explains.
While most varicoceles are harmless, a new or worsening varicocele, especially on the right side, should be evaluated by your doctor.
Symptoms in women
Women are typically diagnosed later than men, as some of the vague symptoms women experience are incorrectly attributed to urinary tract infections or hormone-related changes, Kazanjian says.
Some of these symptoms include:
— Bloating
— Pelvic pain
— Pain with urination
“Anecdotally, some women may be treated for a urinary tract infection in urgent care or in the emergency room setting before a true workup for hematuria is initiated,” Phillips says, adding that this may delay a diagnosis. “Urinary tract infections are also less common in men, and hematuria in males may prompt a referral to urology earlier than in women.”
When to see a doctor
Any one kidney cancer symptom could have a more benign explanation. So when should you see a doctor?
— If these symptoms persist for more than 14 days
— If you have risk factors for kidney cancer, such as smoking, obesity, high blood pressure or family history
— If you feel like your symptoms are different, worsening or making you feel uneasy, it’s the right decision to seek medical evaluation. Ask your doctor, “Could this be related to my kidneys?”
Your doctor may stress preventive measures to reduce your risk, and ideally, they’ll find a disease before it causes symptoms.
“The earlier a cancer is detected, the better the prognosis and the less intensive the treatment,” Kazanjian says.
Frequently asked questions
What are the first signs of kidney cancer?
Early kidney cancer often causes no symptoms at all. When symptoms do appear, they can include blood in the urine, pain on the side of the lower back or a lump in the abdomen.
Can kidney cancer be cured?
Yes, kidney cancer is often cured, especially when found early. Treatment includes surgery, ablation, chemotherapy or medications, such as tyrosine kinase inhibitors, which work by blocking key proteins in cancer cells.
What is the difference between benign and cancerous kidney symptoms?
Benign kidney masses often cause no symptoms because they are typically found by accident on imaging that was ordered for something else. Cancerous tumors are more likely to cause symptoms such as weight loss, blood in the urine, flank pain or abdominal masses.
Does kidney cancer always cause pain?
No, kidney cancer does not always cause pain, as the majority of kidney cancers do not cause any symptoms at all in their early stages. Pain is usually present once the kidney tumor grows large enough to obstruct the kidneys or has spread to other organs in the body.
Can a UTI be a sign of kidney cancer?
The symptoms of UTIs and kidney cancer can overlap.
“Some patients with blood in the urine are treated repeatedly for a UTI when the real source of their bleeding is a tumor in the kidney or tumor in the bladder,” Jayram says.
How is kidney cancer usually found?
Most patients with kidney cancer are found “accidentally” when they present with other, unrelated symptoms, Jayram says.
“Typically, patients undergo abdominal imaging for symptoms such as abdominal pain, gastrointestinal complaints or musculoskeletal issues,” he adds.
What is the best hospital to treat kidney cancer?
U.S. News evaluated nearly 886 hospitals for cancer treatment and ranked the top 50 that treat cancers such as leukemia, lymphoma, melanoma, breast, kidney, colon, prostate, pancreatic, head and neck, orthopedic, uterine and ovarian cancers. Check out the U.S. News & World Report Best Hospitals for Cancer to learn more.
Kidney cancer signs and symptoms
Your doctor should investigate further if you experience any of these potential kidney cancer symptoms:
— Hematuria
— Abdominal mass
— Flank pain
— Unexplained weight loss
— Chronic fatigue
— Persistent fever or night sweats
— Anemia
— High blood pressure or swelling
— Symptoms that look like something else
— Shortness of breath
— Bone pain
— Persistent cough
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Kidney Cancer Symptoms: Early Warning Signs and What to Look For originally appeared on usnews.com
Update 02/06/26: This story was previously published at an earlier date and has been updated with new information.