Renal Cell Carcinoma

What is renal cell carcinoma?

Renal cell carcinoma is the most common type of kidney cancer in adults. The word “renal” refers to the kidneys, the two bean-shaped organs located toward the back of the abdomen, just below the rib cage. The kidneys filter waste products from the blood and turn them into urine. “Carcinoma” is the medical term for a cancer that starts in the cells lining the surfaces of organs. In renal cell carcinoma, the cancer begins in the lining of the small tubes inside the kidney, called tubules, which are part of the kidney’s filtering system.

For readers asking what is renal cell carcinoma in the simplest terms: it is a growth of abnormal cells in the kidney that can form a tumor and, if left untreated, may spread to other parts of the body. It usually develops in one kidney, although in a small number of cases it can affect both.

Renal cell carcinoma most often affects adults between roughly 60 and 70 years of age, and it is more common in men than in women. It is uncommon in people under 45 and rare in children, who tend to develop different kidney tumors. There are several subtypes of renal cell carcinoma. The most common is called clear cell renal cell carcinoma, named for how the cells look under a microscope. Less common subtypes include papillary and chromophobe renal cell carcinoma. The subtype matters because it can influence how the cancer behaves and which treatments may work best.

Many kidney tumors today are found early, often by accident, when a person has an imaging scan of the abdomen for an unrelated reason. Cancers found at an early stage, while still confined to the kidney, are generally more treatable than cancers that have spread.

Symptoms of renal cell carcinoma

In its early stages, renal cell carcinoma often causes no symptoms at all. The kidneys sit deep in the body, so a small tumor can grow without being felt or noticed. This is why many cases are discovered incidentally on scans done for other health problems. When renal cell carcinoma symptoms do appear, they tend to develop as the tumor grows larger or begins to affect nearby structures.

Possible symptoms include:

• Blood in the urine (hematuria) — the urine may look pink, red, or cola-colored; sometimes the blood is only visible under a microscope during a urine test.
• Pain in the side or lower back (flank pain) — usually a persistent, dull ache on one side that does not go away.
• A lump or mass that can be felt in the side or abdomen.
• Unexplained weight loss — losing weight without trying.
• Loss of appetite.
• Ongoing fatigue — feeling unusually tired despite adequate rest.
• Fever that keeps coming back and is not caused by an infection.
• Anemia — a low red blood cell count, which can cause tiredness, paleness, and shortness of breath.
• Night sweats.
• Swelling of the legs or ankles.

Doctors sometimes describe a “classic triad” of blood in the urine, flank pain, and a palpable mass, but in practice most patients do not have all three, and having all three often suggests a more advanced tumor. Symptoms can also differ depending on the stage. Early-stage tumors are usually silent. Larger or more advanced tumors are more likely to cause pain, visible blood in the urine, or general symptoms such as weight loss and fever. If the cancer has spread (metastasized) to other organs, it can cause symptoms related to those areas — for example, bone pain if it has reached the bones, or a cough and shortness of breath if it has reached the lungs.

Renal cell carcinoma can also cause what doctors call paraneoplastic syndromes. These are effects produced by substances the tumor releases into the bloodstream, and they can include high blood pressure, high calcium levels in the blood, an abnormally high red blood cell count, or liver test abnormalities, even before the tumor itself causes local symptoms.

It is important to remember that all of these symptoms are far more often caused by conditions other than cancer, such as urinary tract infections or kidney stones. Only a medical evaluation can determine the cause.

Causes and risk factors

Like most cancers, renal cell carcinoma develops when cells in the kidney acquire changes (mutations) in their DNA that make them grow and divide uncontrollably. In most cases, doctors cannot point to a single cause in an individual patient. However, research has identified several factors that raise the risk. When people search for renal cell carcinoma causes, these risk factors are usually what is meant.

• Smoking. Tobacco use is one of the most well-established risk factors, and the risk appears to increase with the amount and duration of smoking. Quitting reduces the risk over time.
• Obesity. Excess body weight is consistently linked to a higher risk of kidney cancer.
• High blood pressure (hypertension). Long-standing high blood pressure is associated with an increased risk.
• Advanced kidney disease and long-term dialysis. People with chronic kidney failure, especially those on dialysis for many years, have a higher risk of developing kidney tumors.
• Family history. Having a close relative, such as a parent or sibling, with kidney cancer modestly increases risk.
• Inherited genetic conditions. Certain rare syndromes, such as von Hippel–Lindau disease (an inherited condition that causes tumors and cysts in several organs), hereditary papillary renal cell carcinoma, and Birt–Hogg–Dubé syndrome, greatly increase the likelihood of kidney tumors, often at a younger age and sometimes in both kidneys.
• Male sex and older age. The disease is more common in men and in people over 60.
• Workplace exposures. Long-term exposure to certain substances, such as trichloroethylene (an industrial solvent) and cadmium, has been linked to kidney cancer in some studies.
• Certain long-term medication use. Prolonged heavy use of some pain relievers has been associated with kidney damage and, in some research, with a higher risk of kidney cancer.

Having one or more risk factors does not mean a person will develop renal cell carcinoma, and some people who develop it have no known risk factors. Still, avoiding tobacco, maintaining a healthy weight, and controlling blood pressure are sensible steps that support kidney health in general.

Diagnosis of renal cell carcinoma

Renal cell carcinoma diagnosis usually starts when a doctor investigates symptoms such as blood in the urine, or when a mass is spotted on a scan done for another reason. The evaluation typically involves several steps.

Medical history and physical examination

The doctor will ask about symptoms, smoking history, medications, family history of cancer, and any inherited conditions. A physical examination may include checking the abdomen and flank for a mass or tenderness and measuring blood pressure.

Laboratory tests

Blood and urine tests cannot confirm kidney cancer by themselves, but they provide important information. A urinalysis (a laboratory examination of the urine) can detect blood that is not visible to the eye. Blood tests can assess kidney function, red blood cell counts, calcium levels, and liver function — all of which can be affected by renal cell carcinoma and are important for planning treatment.

Imaging tests

Imaging is the cornerstone of diagnosis. Commonly used tests include:

• Ultrasound — a painless scan using sound waves, often the first test, which can distinguish a solid tumor from a simple fluid-filled cyst.
• CT scan (computed tomography) — a detailed X-ray-based scan, usually performed with an injected contrast dye. A CT scan of the abdomen is often the key test for characterizing a kidney mass and checking whether it has grown beyond the kidney or spread to lymph nodes.
• MRI (magnetic resonance imaging) — a scan using magnetic fields, useful when CT contrast dye cannot be used, or to evaluate whether the tumor extends into nearby blood vessels.
• Chest imaging — a chest X-ray or CT scan to check whether the cancer has spread to the lungs, one of the more common sites of spread. Bone scans or brain imaging may be added if symptoms suggest spread to those areas.

Biopsy

A biopsy means removing a small sample of tissue with a needle so it can be examined under a microscope. Unlike many other cancers, renal cell carcinoma can often be diagnosed with reasonable confidence from imaging alone, and in many cases surgery proceeds without a prior biopsy. However, a biopsy may be recommended when the diagnosis is uncertain, when a non-surgical treatment is being considered, or when confirming the cancer type would change the treatment plan.

Staging

Once renal cell carcinoma is confirmed or strongly suspected, doctors assign a stage, which describes the size of the tumor and how far it has spread. Broadly, early stages mean the tumor is confined to the kidney; later stages mean it has grown into nearby tissues, involved lymph nodes, or spread to distant organs. Staging guides treatment decisions and helps doctors discuss the outlook.

Treatment options for renal cell carcinoma

Renal cell carcinoma treatment depends on the stage of the disease, the subtype of the tumor, the person’s overall health, and how well the kidneys are working. Care is usually planned by a team that may include a urologist (a surgeon specializing in the urinary system), a medical oncologist (a cancer medicine specialist), and radiology specialists. In many hospital systems, including Acibadem, drug-based cancer care for this condition is coordinated through the Medical Oncology Department, working alongside urologic surgeons.

Active surveillance (watchful waiting)

For some small kidney tumors, particularly in older patients or those with other serious health conditions, doctors may recommend active surveillance. This means monitoring the tumor with regular imaging scans rather than treating it immediately. Many small kidney tumors grow slowly, and in carefully selected patients this approach can avoid or delay the risks of surgery. Treatment is offered if the tumor grows or changes.

Surgery

Surgery is the main treatment for renal cell carcinoma that has not spread, and it offers the best chance of removing the cancer completely at early stages. The two main operations are:

• Partial nephrectomy — removal of the tumor along with a margin of surrounding kidney tissue, leaving the rest of the kidney in place. This is often preferred for smaller tumors because it preserves kidney function.
• Radical nephrectomy — removal of the entire affected kidney, sometimes together with nearby tissue or lymph nodes, generally used for larger or more centrally located tumors.

Both operations can often be performed with minimally invasive techniques, such as laparoscopic or robot-assisted surgery, which use small incisions and may allow a shorter recovery, although open surgery is still appropriate in some situations. Most people can live a healthy life with one functioning kidney, though kidney function is monitored afterward.

Ablation procedures

For small tumors in patients who are not good candidates for surgery, doctors may consider ablation — destroying the tumor without removing it. Options include cryoablation, which freezes the tumor, and radiofrequency ablation, which uses heat. These are typically done through a needle guided by imaging.

Systemic (drug) treatment

When renal cell carcinoma has spread beyond the kidney, or when there is a significant risk of it returning after surgery, drug treatments that work throughout the body may be recommended. These include:

• Targeted therapy — medicines that block specific signals cancer cells use to grow and to build the blood vessels that feed the tumor.
• Immunotherapy — medicines that help the body’s own immune system recognize and attack cancer cells. Immunotherapy, alone or combined with targeted therapy, is now a standard approach for many patients with advanced renal cell carcinoma.

Notably, traditional chemotherapy is generally not very effective against most renal cell carcinomas, which is why targeted therapy and immunotherapy play such a central role.

Radiation therapy

Radiation therapy, which uses focused beams of energy to destroy cancer cells, is not usually the main treatment for kidney tumors. However, it can be helpful for relieving symptoms, such as pain from cancer that has spread to the bones or brain.

Your care team may combine these approaches, and treatment plans are often adjusted over time based on how the cancer responds. Asking your doctors to explain the goal of each treatment — cure, control, or symptom relief — can help you take part in decisions.

Living with renal cell carcinoma and outlook

The outlook for renal cell carcinoma varies widely and depends mainly on the stage at diagnosis, the tumor subtype and grade, and the person’s overall health. In general, cancers found while still confined to the kidney have a favorable outlook after surgery, and many patients in this situation are cured. Cancers that have spread to distant organs are more difficult to treat; they are often not curable, but modern immunotherapy and targeted therapy can control the disease for meaningful periods in many patients. No doctor can promise a specific outcome, and statistics describe groups of patients, not individuals.

After treatment, regular follow-up is important. This usually includes periodic imaging scans and blood tests to check kidney function and to detect any recurrence early. People who have had a kidney removed are generally advised to protect their remaining kidney by controlling blood pressure and blood sugar, staying hydrated, avoiding tobacco, and using caution with medications that can strain the kidneys — always in consultation with their doctor.

Healthy lifestyle habits — a balanced diet, regular physical activity as tolerated, maintaining a healthy weight, and not smoking — support recovery and general health. Living with a cancer diagnosis can also be emotionally demanding; many patients benefit from counseling, support groups, or simply honest conversations with their care team about fears and expectations.

Frequently asked questions

What is renal cell carcinoma in simple terms?

Renal cell carcinoma is the most common form of kidney cancer in adults. It begins in the cells that line the tiny filtering tubes inside the kidney. It usually affects one kidney and is most often diagnosed in people over 60. Found early, it is frequently treatable with surgery.

What are the first symptoms of renal cell carcinoma?

Often there are no early symptoms, and many tumors are found by chance on scans done for other reasons. When renal cell carcinoma symptoms do occur, the most common are blood in the urine, a persistent ache in the side or lower back, unexplained weight loss, fatigue, and fever. These symptoms have many possible causes, so a medical evaluation is needed to find the explanation.

Can renal cell carcinoma be cured?

In many cases, yes — particularly when the cancer is confined to the kidney and can be completely removed with surgery. When the cancer has spread to other organs, a cure is less likely, but modern treatments such as immunotherapy and targeted therapy can often control the disease for a considerable time. The realistic goal of treatment depends on the stage, and your care team can explain what is achievable in your situation.

How serious is renal cell carcinoma?

It ranges from highly treatable to life-threatening, depending largely on the stage at diagnosis. Small tumors confined to the kidney generally have a good outlook after treatment, while cancer that has spread to distant organs is more serious and harder to treat. The tumor’s subtype and grade, and the patient’s general health, also influence the outcome.

What causes renal cell carcinoma?

There is usually no single identifiable cause. Known risk factors include smoking, obesity, high blood pressure, advanced kidney disease requiring long-term dialysis, a family history of kidney cancer, and certain rare inherited conditions such as von Hippel–Lindau disease. Some workplace chemical exposures may also raise risk. Many people who develop the disease have no obvious risk factors.

How is renal cell carcinoma diagnosed?

Diagnosis typically relies on imaging — usually an ultrasound followed by a CT scan or MRI with contrast dye — together with blood and urine tests. Unlike many cancers, renal cell carcinoma can often be identified with high confidence on imaging alone, so a needle biopsy is not always required before treatment, although it is used in certain situations.

Can you live a normal life with one kidney after surgery?

In most cases, yes. A single healthy kidney can usually do the work of two, and many people live full, active lives after a nephrectomy. Doctors generally advise regular check-ups, blood pressure control, a healthy lifestyle, and caution with medications that can affect the kidneys to protect the remaining organ.

How long is recovery after kidney cancer surgery?

Recovery varies with the type of operation and the person’s overall health. Minimally invasive (laparoscopic or robot-assisted) surgery often allows a shorter hospital stay and a return to light activities within a few weeks, while open surgery may require a longer recovery. Your surgical team will give you individualized guidance on activity, lifting, and follow-up scans.

When to see a doctor

Make an appointment with a doctor if you notice any persistent change in your urinary habits, ongoing pain in your side or back, or general symptoms such as unexplained weight loss, recurring fever, or lasting fatigue. These symptoms usually have benign causes, but they deserve evaluation, especially if they do not improve.

Seek medical attention promptly if you experience any of the following red-flag warning signs:

• Visible blood in the urine — even if it happens only once and then stops.
• A lump or mass you can feel in your side or abdomen.
• Persistent pain in the flank or lower back on one side that does not go away with rest.
• Unexplained weight loss or loss of appetite lasting more than a few weeks.
• Recurring fever or night sweats with no clear infection.
• New bone pain, persistent cough, or shortness of breath in someone with a known kidney tumor, which could suggest spread.
• Severe fatigue, paleness, or breathlessness that could indicate anemia.

People with a strong family history of kidney cancer or a known inherited condition such as von Hippel–Lindau disease should discuss regular screening with their doctor, since early detection greatly improves the chances of successful renal cell carcinoma treatment. If you have already been diagnosed and develop new or worsening symptoms between appointments, inform your care team rather than waiting for the next scheduled visit.