Kidney Cancer

Overview
Epidemiology
Pathophysiology
Etiology and Risk Factors
Clinical Presentation
Diagnosis
Treatment
Complications
Prognosis
Prevention
Recent Research and Advances
Research Papers
Connections
Featured Videos

1. Overview

Kidney cancer — known medically as renal cell carcinoma (RCC) when it arises from the lining of the tiny filtering tubes inside the kidney — is a malignancy of one of the two bean-shaped organs that clean your blood, balance your fluids and salts, control your blood pressure, and make hormones that build red blood cells and activate vitamin D. RCC accounts for roughly 90% of all kidney cancers in adults. (The remaining tumors include urothelial cancers of the renal pelvis, which behave more like bladder cancer, and rare childhood tumors such as Wilms tumor — those are not the subject of this page.)

Here is the single most important thing to understand about kidney cancer today, because it changes how the rest of this page should be read: most kidney cancers are now found by accident. Someone gets a CT scan or ultrasound for belly pain, a kidney stone, a car accident, or an unrelated checkup, and the radiologist spots a small mass on the kidney that nobody was looking for. These incidentally discovered tumors are usually small, early, and curable. The old textbook picture of kidney cancer — a person showing up with pain, bloody urine, and a lump you can feel — still exists, but it now signals advanced disease and has become uncommon. The shift from "found because it caused symptoms" to "found by accident while it was still silent" is the best news in this field, and it explains why survival has been quietly improving for decades.

Kidney cancer is not one disease but a family of subtypes with different biology and different outlooks. Clear cell RCC is the most common, making up about 75% of cases, and it is the subtype that drives most of the modern drug story (described in plain terms below). Papillary RCC (~10–15%) and chromophobe RCC (~5%) are less common and, stage for stage, often carry a better prognosis than clear cell. Knowing the subtype matters because it shapes treatment and follow-up.

2. Epidemiology

In the United States, roughly 82,000 new cases of kidney and renal-pelvis cancer are diagnosed each year, with about 14,000–15,000 deaths. It is among the ten most common cancers in both men and women, and it is about twice as common in men as in women. Most diagnoses come in the sixth and seventh decades of life, with a median age around 64. Black Americans have a modestly higher incidence and, in some studies, worse outcomes — differences thought to reflect a mix of biology, higher rates of high blood pressure and obesity, and unequal access to early imaging and specialist care.

Incidence has risen steadily over the past several decades. The honest interpretation is that most of that rise reflects detection, not a true epidemic. As CT and ultrasound became routine for everything from abdominal pain to trauma, more small, slow-growing tumors were caught early — tumors that in an earlier era would have stayed silent for years or never caused harm at all. A genuine increase in risk factors such as obesity and high blood pressure has contributed too, but the incidental-detection effect is the dominant story. The reassuring side of this is a downward stage shift: a much larger share of kidney cancers are now diagnosed while still confined to the kidney, where cure rates are high.

3. Pathophysiology

To understand why clear cell kidney cancer behaves the way it does — and why today's best drugs work — it helps to follow one elegant piece of biology: how cells sense oxygen.

Every cell needs a way to know when oxygen is running low so it can adapt — for example, by triggering new blood-vessel growth to bring in more supply. The master switch for this is a protein called HIF (hypoxia-inducible factor). When oxygen is plentiful, a "garbage tag" gets placed on HIF and it is rapidly destroyed, so it never builds up. The protein that places that garbage tag is called VHL (von Hippel–Lindau). Think of VHL as a quality-control inspector that catches HIF and sends it to the shredder whenever oxygen is normal.

In the vast majority of clear cell kidney cancers, the VHL gene is switched off or lost. With no inspector on duty, HIF piles up even when oxygen is perfectly normal. The cell behaves as if it were starved of oxygen all the time: it screams for new blood vessels (by pumping out VEGF, the blood-vessel growth signal) and rewires its metabolism for growth. That is why clear cell tumors are so richly supplied with blood vessels, and it is the reason a whole class of drugs that block VEGF and its receptors works in this disease.

This oxygen-sensing pathway is not a footnote — it is one of the great discoveries of modern biology. The scientists who worked out exactly how cells sense and respond to oxygen, including the VHL–HIF connection, were awarded the 2019 Nobel Prize in Physiology or Medicine. What makes kidney cancer special is that this Nobel-level basic science translated directly into treatment: drugs that block VEGF, and newer drugs that block HIF itself (such as belzutifan), grew straight out of understanding the VHL–HIF circuit. Few cancers have such a clean line from a fundamental discovery to a pill in a patient's hand.

4. Etiology and Risk Factors

Kidney cancer usually develops from a combination of acquired DNA damage over a lifetime plus, in a minority of people, an inherited predisposition. The best-established modifiable risk factors are:

Smoking. Tobacco roughly increases kidney-cancer risk by 30–50%, and risk rises with how much and how long a person smokes. Quitting lowers risk over time. This is the single most actionable risk factor.
Obesity. Excess body weight is one of the strongest links, especially in women, and the risk climbs with rising body-mass index. Fat tissue alters hormones and growth signals in ways that favor tumor development.
High blood pressure (hypertension). Long-standing high blood pressure independently raises risk, separate from obesity. The relationship between specific blood-pressure medications (such as diuretics) and kidney cancer has been debated for years. The fair reading of the evidence is that the elevated blood pressure itself appears to be the driver, and any signal tied to particular drugs is hard to separate from the condition they treat — so do not stop a needed blood-pressure medicine over kidney-cancer worry. Controlling blood pressure is protective on balance.
Chronic kidney disease and dialysis. People with advanced kidney disease, and especially those on long-term dialysis, can develop acquired cystic kidney disease, which carries a meaningfully higher risk of kidney cancer — one reason these patients are often imaged periodically.

Inherited (hereditary) kidney cancer accounts for a small share — roughly 3–5% of cases — but identifying it matters enormously for the patient and their family. The best-known syndrome is von Hippel–Lindau (VHL) disease, caused by an inherited fault in the same VHL gene described above; affected people can develop multiple kidney tumors, often in both kidneys, plus tumors in the eye, brain, spine, and adrenal glands. Other inherited syndromes include hereditary papillary RCC, Birt–Hogg–Dubé, and hereditary leiomyomatosis and RCC (HLRCC).

Who should be offered genetic counseling and testing? Consider it when kidney cancer appears at a young age (roughly under 46), when there are tumors in both kidneys or multiple tumors in one kidney, when there is a family history of kidney cancer or related tumors, or when a specific syndrome is suspected from other findings. Genetic testing can change screening (relatives may need monitoring), the timing and type of surgery, and even drug choice.

5. Clinical Presentation

The classic teaching triad of kidney cancer is flank pain + visible blood in the urine + a mass you can feel in the side. It is worth being blunt: this classic triad is now rare, appearing in well under 10% of patients, and when all three are present it usually means the cancer is already advanced. The kidney sits deep in the back of the abdomen, so a tumor can grow for a long time without producing any symptom at all. That silence is exactly why so many kidney cancers today are found incidentally on a scan done for something else.

When symptoms do occur, the most important one to act on is blood in the urine (hematuria). This deserves its own emphasis: even a single episode of painless, visible blood in the urine always deserves a medical evaluation. It is tempting to dismiss one pink or red urine and move on, but painless visible blood is a red flag for cancers of the urinary tract — kidney and bladder among them — and the workup is straightforward. Do not wait for it to "happen again."

Other possible symptoms include a dull, persistent ache in the flank or back; a lump felt in the abdomen or side; unexplained weight loss; fatigue; fever without infection; and, in men, a new swelling of veins in the scrotum (varicocele) that does not go down when lying flat. Kidney cancer is also famous for paraneoplastic syndromes — effects produced by substances the tumor releases — such as a high blood-calcium level, high red-blood-cell count, or abnormal liver tests that resolve after the kidney is treated.

6. Diagnosis

The cornerstone of diagnosis is cross-sectional imaging, almost always a CT scan of the abdomen with and without intravenous contrast. The key feature radiologists look for is enhancement: a solid kidney mass that "lights up" when contrast is injected is suspicious for cancer, because tumors recruit blood vessels. MRI is an excellent alternative, especially for people who cannot receive CT contrast or have reduced kidney function. A chest CT and lab work complete the staging picture, since kidney cancer can spread to the lungs, bones, liver, and lymph nodes.

An important and underappreciated point: not every kidney mass is cancer. Among small enhancing renal masses (loosely, those under about 4 cm), roughly 20% turn out to be benign on final pathology. The two most common benign mimics are oncocytoma (a usually harmless tumor that can look identical to cancer on a scan) and fat-poor angiomyolipoma (AML) (a benign tumor that is hard to distinguish because it lacks the obvious fat that normally gives it away). This is precisely why aggressive treatment of every small mass is not automatically the right answer.

Renal mass biopsy — taking a needle sample of the tumor — has become more accepted for exactly this reason. A biopsy can often tell whether a small mass is cancer, what subtype it is, and how aggressive it looks, which helps a patient and doctor decide between surgery, ablation, and watchful waiting. Biopsy is not needed in every case (a large mass that will be removed regardless does not require one), but it is a reasonable, well-studied tool when the result would change the plan.

Kidney cancer is staged with the TNM system, and stage drives everything that follows: a tumor confined to the kidney (stage I–II) is treated and followed very differently from one that has spread to lymph nodes (stage III) or distant organs (stage IV).

7. Treatment

Treatment depends heavily on stage, tumor size, the patient's other health problems, and how well their kidneys are working. The guiding principle for localized disease is to cure the cancer while protecting as much working kidney as possible.

Surgery is the mainstay for localized kidney cancer:

Partial nephrectomy (nephron-sparing surgery) — removing only the tumor plus a rim of normal tissue and leaving the rest of the kidney in place — is the preferred approach whenever it is feasible, especially for smaller tumors. The reason is straightforward: keeping more kidney tissue protects long-term kidney function, which matters for heart health and longevity over the years that follow. Cancer-control outcomes are excellent and comparable to removing the whole kidney for appropriate tumors.
Radical nephrectomy — removing the entire kidney — is used for larger or more complex tumors, or when partial removal is not safe.
Thermal ablation (freezing the tumor with cryoablation, or heating it with radiofrequency or microwave energy) is an option for some small tumors, particularly in older patients or those who are poor surgical candidates.

Active surveillance — deliberately watching a small tumor instead of treating it right away — is a legitimate, evidence-based choice for selected patients. For older adults or those with significant other illnesses, a small kidney mass may grow slowly enough that the risks of surgery outweigh the risk of the cancer over their remaining life expectancy. The DISSRM prospective registry showed that carefully selected patients managed with surveillance had cancer-specific survival comparable to those treated immediately, with treatment held in reserve if the tumor grew or changed. Surveillance is not "doing nothing" — it is structured monitoring with imaging, with intervention available the moment it becomes warranted.

A point that surprises many patients: kidney cancer is not treated with traditional chemotherapy, because it is intrinsically chemoresistant. The kidney's normal job is to filter and pump out toxins, and RCC cells retain pumps that expel chemotherapy drugs before they can work. For decades this made advanced kidney cancer very hard to treat — but that resistance is no longer the bad news it used to be, because the drugs that do work in RCC are immunotherapy and targeted therapy, not chemo:

Adjuvant immunotherapy. For patients at high risk of the cancer returning after surgery, the KEYNOTE-564 trial showed that one year of the immunotherapy drug pembrolizumab after surgery improved disease-free survival, and a later analysis demonstrated an overall survival benefit — the first adjuvant therapy in RCC to extend life.
Metastatic combinations. For cancer that has already spread, the standard first-line treatments are now combinations. The CheckMate-214 trial established ipilimumab plus nivolumab (dual immunotherapy) for intermediate- and poor-risk patients, improving survival versus the older targeted drug sunitinib. The KEYNOTE-426 trial established pembrolizumab plus axitinib (immunotherapy plus a targeted drug), also beating sunitinib on survival and response. Other immunotherapy-plus-targeted combinations are likewise standard.
Cytoreductive nephrectomy — a nuance. Removing the primary kidney tumor even when cancer has already spread used to be routine. The CARMENA trial showed that in the modern drug era, many patients with metastatic disease do not need their kidney removed first — drug therapy alone is reasonable for higher-risk patients — though removing the kidney still has a role for selected patients with limited spread or troublesome local symptoms. The decision is individualized.
HIF-blocking therapy. Belzutifan, a drug that directly blocks the HIF pathway described earlier, is approved for certain VHL-associated kidney tumors and is used in advanced disease — a clean example of the oxygen-sensing science turning into treatment.

It is worth naming what does not have a role: adjuvant targeted therapy (TKIs) after surgery was tested in the ASSURE trial and did not improve outcomes, so it is not used. Knowing what was tried and didn't work is part of honest care.

8. Complications

Complications come from three directions: the cancer, the surgery, and life afterward. The cancer itself can spread — most often to the lungs, then bones, liver, brain, and lymph nodes — and can cause the paraneoplastic effects noted earlier (high calcium, high red-cell count, abnormal liver tests). Locally advanced tumors can grow into the large vein draining the kidney (the renal vein) and even up the inferior vena cava toward the heart, which complicates surgery.

After surgery, the central long-term concern is kidney function. Removing a whole kidney leaves a person with one, and partial removal sacrifices some tissue; both can nudge someone toward chronic kidney disease, which is one of the main reasons nephron-sparing partial nephrectomy is preferred when possible. The good news is reassuring and worth stating plainly: most people live full, normal lives with one kidney. A single healthy kidney enlarges slightly and takes over most of the work of two.

Practical steps to protect a remaining kidney: keep blood pressure well controlled, stay adequately hydrated, manage diabetes if present, be cautious with NSAID pain relievers (ibuprofen, naproxen) and other drugs hard on the kidneys, and have kidney function checked periodically. None of this requires a dramatic lifestyle — it is mostly the same heart-and-kidney-healthy habits that benefit everyone.

9. Prognosis

Outlook in kidney cancer depends overwhelmingly on stage at diagnosis, and the numbers are genuinely encouraging at the early end. For localized kidney cancer (confined to the kidney), the five-year relative survival is approximately 93% — the great majority of these patients are cured by surgery alone. This is exactly why the rise in incidental detection has been such a quiet victory: more cancers caught while still localized means more cures.

When cancer has spread to distant organs, survival has historically been poor — in the range of 15–20% at five years. But this is one of the clearest examples in oncology of statistics that are actively improving: the immunotherapy combinations described above have meaningfully extended survival for metastatic patients over the past decade, and a subset achieve durable, long-lasting responses that were almost unheard of before. Any survival figure quoted from older data understates what modern treatment now achieves.

Kidney cancer also has a genuine biological curiosity worth mentioning honestly, because patients sometimes hear about it and wonder: spontaneous regression — a tumor shrinking on its own without treatment — has been documented in RCC. It is real, but it is extraordinarily rare (well under 1% of cases), unpredictable, and not something anyone can count on or chase. Its main value is as a clue that the immune system can sometimes recognize and attack kidney cancer — the same insight that immunotherapy now harnesses deliberately and reliably.

After treatment, patients enter a follow-up imaging schedule tailored to their stage and subtype — more intensive for higher-risk tumors, lighter for small low-risk ones. A typical plan involves periodic chest and abdominal imaging (CT or sometimes ultrasound/MRI) plus blood work over several years, the goal being to catch any recurrence early when it is most treatable.

10. Prevention

There is no proven way to guarantee prevention of kidney cancer, and — importantly — there is no recommended screening test for kidney cancer in the general population. Unlike colon or breast cancer, the disease is not common enough, and no screening test accurate enough, to make routine screening of average-risk people worthwhile. (People with hereditary syndromes such as VHL, or those on long-term dialysis with acquired cystic disease, are a different story and are monitored individually.)

What does reduce risk is largely the modifiable risk factors turned into goals:

Don't smoke, and quit if you do. This is the most effective single step, and risk falls over time after quitting.
Keep a healthy weight. Obesity is one of the strongest links, so weight management genuinely lowers risk.
Control blood pressure. Treating high blood pressure is protective on balance — and do not avoid needed medication out of misplaced cancer fear.
Limit exposure to known kidney-cancer chemicals such as trichloroethylene and cadmium, mainly an occupational concern.
Get visible blood in the urine checked — not prevention exactly, but the closest thing to early detection most people have.

11. Recent Research and Advances

Kidney cancer has gone from one of the most treatment-resistant solid tumors to one of immunotherapy's success stories in barely fifteen years, and the pace is still accelerating. Several threads are worth following:

Immunotherapy moving earlier. The success of adjuvant pembrolizumab (KEYNOTE-564) in extending survival after surgery has pushed researchers to test immunotherapy even before surgery and in lower-risk settings, aiming to cure more people the first time around. Trials are refining exactly which patients benefit most, to avoid over-treating those already cured by surgery.

Drugging the oxygen-sensing pathway directly. Belzutifan, the first-in-class HIF-2α inhibitor, validated the idea of hitting the VHL–HIF circuit head-on rather than just blocking the blood vessels it summons. Next-generation HIF-targeting agents and rational combinations with immunotherapy are an active area, building straight on the Nobel-recognized biology.

Better molecular maps and biomarkers. Large genomic studies have detailed the mutations and pathways that distinguish RCC subtypes, helping explain why clear cell, papillary, and chromophobe tumors behave differently and pointing toward subtype-specific treatment. The open challenge is a reliable biomarker to predict which patients will respond to which immunotherapy — so treatment can be matched rather than tried.

Smarter management of the small renal mass. Research continues to sharpen the tools — improved imaging, renal mass biopsy, and longer follow-up of active-surveillance cohorts like DISSRM — so that benign and indolent tumors are spared unnecessary surgery while dangerous ones are caught and treated. The goal is fewer operations on tumors that never needed them, without missing the ones that do.

12. References & Research

Historical Background

Kidney cancer's history is partly a history of getting the biology wrong, then right. In 1883, the pathologist Paul Grawitz proposed that these tumors arose from misplaced adrenal-gland tissue, coining the term "hypernephroma" — a now-discarded misnomer that nonetheless lingered in medical language for a century. The surgical era was defined by the radical nephrectomy, standardized by Robson in the 1960s, which for decades was the one reliable cure. The modern molecular era opened in 1993, when Latif and colleagues identified the von Hippel–Lindau (VHL) tumor-suppressor gene, the genetic root of both the inherited syndrome and most sporadic clear cell tumors. The decisive payoff came from basic science: the discovery of how cells sense oxygen through the VHL–HIF pathway earned the 2019 Nobel Prize in Physiology or Medicine, and — unusually — that fundamental insight led directly to the targeted and HIF-blocking drugs that treat patients today.

Key Research Papers

Siegel RL, Giaquinto AN, Jemal A. Cancer statistics, 2024. CA: A Cancer Journal for Clinicians. 2024;74(1):12-49.
Hsieh JJ, Purdue MP, Signoretti S, et al. Renal cell carcinoma. Nature Reviews Disease Primers. 2017;3:17009.
The Cancer Genome Atlas Research Network. Comprehensive molecular characterization of clear cell renal cell carcinoma. Nature. 2013;499(7456):43-49.
Ivan M, Kondo K, Yang H, et al. HIFα targeted for VHL-mediated destruction by proline hydroxylation: implications for O₂ sensing. Science. 2001;292(5516):464-468.
Latif F, Tory K, Gnarra J, et al. Identification of the von Hippel-Lindau disease tumor suppressor gene. Science. 1993;260(5112):1317-1320.
Chow WH, Gridley G, Fraumeni JF, Järvholm B. Obesity, hypertension, and the risk of kidney cancer in men. New England Journal of Medicine. 2000;343(18):1305-1311.
Hunt JD, van der Hel OL, McMillan GP, Boffetta P, Brennan P. Renal cell carcinoma in relation to cigarette smoking: meta-analysis of 24 studies. International Journal of Cancer. 2005;114(1):101-108.
Marconi L, Dabestani S, Lam TB, et al. Systematic review and meta-analysis of diagnostic accuracy of percutaneous renal tumour biopsy. European Urology. 2016;69(4):660-673.
Pierorazio PM, Johnson MH, Ball MW, et al. Five-year analysis of a multi-institutional prospective clinical trial of delayed intervention and surveillance for small renal masses: the DISSRM registry. European Urology. 2015;68(3):408-415.
Van Poppel H, Da Pozzo L, Albrecht W, et al. A prospective, randomised EORTC intergroup phase 3 study comparing the oncologic outcome of elective nephron-sparing surgery and radical nephrectomy for low-stage renal cell carcinoma. European Urology. 2011;59(4):543-552.
Campbell S, Uzzo RG, Allaf ME, et al. Renal mass and localized renal cancer: AUA guideline. Journal of Urology. 2017;198(3):520-529.
Haas NB, Manola J, Uzzo RG, et al. Adjuvant sunitinib or sorafenib for high-risk, non-metastatic renal-cell carcinoma (ECOG-ACRIN E2805 / ASSURE): a randomised, double-blind, placebo-controlled trial. The Lancet. 2016;387(10032):2008-2016.
Méjean A, Ravaud A, Thezenas S, et al. Sunitinib alone or after nephrectomy in metastatic renal-cell carcinoma (CARMENA). New England Journal of Medicine. 2018;379(5):417-427.
Choueiri TK, Tomczak P, Park SH, et al. Adjuvant pembrolizumab after nephrectomy in renal-cell carcinoma (KEYNOTE-564). New England Journal of Medicine. 2021;385(8):683-694.
Choueiri TK, Tomczak P, Park SH, et al. Overall survival with adjuvant pembrolizumab in renal-cell carcinoma (KEYNOTE-564). New England Journal of Medicine. 2024;390(15):1359-1371.
Motzer RJ, Tannir NM, McDermott DF, et al. Nivolumab plus ipilimumab versus sunitinib in advanced renal-cell carcinoma (CheckMate-214). New England Journal of Medicine. 2018;378(14):1277-1290.
Rini BI, Plimack ER, Stus V, et al. Pembrolizumab plus axitinib versus sunitinib for advanced renal-cell carcinoma (KEYNOTE-426). New England Journal of Medicine. 2019;380(12):1116-1127.
Jonasch E, Donskov F, Iliopoulos O, et al. Belzutifan for renal cell carcinoma in von Hippel-Lindau disease. New England Journal of Medicine. 2021;385(22):2036-2046.

Research Papers

The links below run live searches on PubMed, the U.S. National Library of Medicine's database of biomedical literature. Use them to find the most recent peer-reviewed studies on kidney cancer (renal cell carcinoma), its biology, and its treatment.

Connections

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