Let's Talk About Kidney Cancer Stages
Knowing how far your condition has progressed will help you better understand your path to treatment. Learn what’s happening in your body and what that means for living with this disease.by Lexi Krupp Health Writer
Once you learn you have kidney cancer—and what type—the next thing your doctor might tell you is how far the disease has advanced. The spread of cancer is grouped into stages, one through four. The higher the number, the more cancer in the body. Knowing your kidney cancer stage helps you gauge how serious the disease is and guides you in deciding what treatment options to follow. We asked the experts to break down the details for each stage.
Our Pro Panel
We went to some of the nation's top experts in cancer to bring you the most up-to-date information possible.
Ithaar Derweesh, M.D.
UC San Diego Health
San Diego, CA
John Leppert, M.D.
Director of Urologic Oncology
Palo Alto Veterans Affairs Health Care System
Palo Alto, CA
Phillip Pierorazio, M.D.
Director, Division of Testis Cancer, Urologist
Johns Hopkins University
Your medical team will typically perform a CT scan of the abdomen to determine the size and location of a tumor, or they’ll use an MRI if they suspect the tumor has spread to a major vein, if you have an allergy to dye used in a CT scan, or if you have impaired kidney function. They may run further imaging tests, including a chest x-ray or CT scan, and depending on your symptoms, a bone scan, a CT scan or MRI of the brain, or imaging of other parts of the body.
Kidney cancers are grouped in stages 1 through 4 depending on the size of the tumor and how far it’s spread. You might also see the letters “T” “N” and “M” to describe the spread of cancer. “T” stands for tumor, and will be accompanied by the stage of cancer, T1 to T4. “N” means nearby lymph nodes. “M” stands for metastasis, which means the cancer has spread beyond the kidney. M0 means the cancer hasn’t spread to other parts of the body, M1 means it has.
Doctors use this information to decide what treatments are best and give you a better sense of your recovery chances. For instance, stage 1 or 2 might involve surgery, while stage 4 is more likely to be treated with drug therapy.
Every person’s cancer and their response to treatment is different. But on average, 75% of people at all stages of kidney cancer live for at least five years after their diagnosis, based on the most recent data available.
Kidney Cancer Recap
Let’s review for a minute: There are about 500,000 Americans living with kidney cancer, and roughly 70,000 new people join their ranks every year. Although it’s one of the top 10 types of cancer you can get in the U.S., the numbers are still relatively low: You have about a 1% lifetime risk of getting kidney cancer if you are a woman and a 2% lifetime risk if you’re a man. So it’s understandable that you probably haven’t spent a whole lot of time thinking about what your kidneys are and how they work.
Here’s what you need to know. The kidneys are two bean-shaped organs that live behind your gut. Their job has four parts:
Filter waste products from your blood.
Maintain fluid balance in the body and make pee.
Help control your blood pressure.
Produce hormones that maintain strong bones and keep your red blood cell count in check.
Tiny pipes called tubules inside each kidney serve as the workspace for the blood-cleaning action to happen. This is also the area where 90% of kidney cancers develop (called renal cell carcinomas) starting with a mass that forms inside these blood-filtering tubes.
What Does a Kidney Cancer Diagnosis Mean?
If there’s a mass growing in your kidneys and it’s at risk of spreading to other parts of your body, that’s cancer. It’s a scary word, but a lot of kidney cancers can be safely managed, and even cured. If you’ve been diagnosed with kidney cancer, how you fare largely depends on how far the tumor has progressed, the type of kidney cancer you have, your age, and your overall health.
To find out what a tumor looks like and where exactly it’s located, your doctor will use imaging tests—typically a computed tomography (CT) scan. Your medical team might also use a magnetic resonance imaging (MRI) instead if you are not a good candidate for a CT scan because of an allergy, limited kidney function, or if there’s a chance a tumor has spread into a major vein (called the inferior vena cava, which an MRI can image better).
With these images in hand, your health care team can figure out what stage of cancer you’re dealing with, and what treatment options make the most sense for you.
What Are the Stages of Kidney Cancer?
Kidney cancer staging usually begins with your doctor breaking things down according to something called the TNM Staging System, which stands for “tumor” (or where the cancer started), “node” (if cancer cells have reached nearby lymph nodes—tiny glands packed with immune cells that help fight infection), and “metastasis” (meaning the cancer has spread throughout the body).
This is how it works:
T: This describes that size and location of the tumor where the cancer originated, from 1 through 4.
N: This indicates if the cancer has spread to nearby lymph nodes (N1) or not (N0), or if your medical team doesn’t know (NX).
M: This shows whether the cancer has spread to other parts of the body (M1), or just stayed in the kidney (M0).
From there, kidney cancer is typically assigned a stage using the 1-4 system or written with Roman numerals (I-IV). Here’s what those numbers mean for your treatment and chances of recovery.
Stage I Kidney Cancer
At stage 1 of this disease, you’re dealing with a small tumor in the kidney. Nearly 60% of kidney cancer patients in the U.S. are diagnosed at this early stage, often when clinicians are doing an unrelated procedure.
At this stage, the tumor is no bigger than 7 cm (just under 3 inches), or no wider than your typical cell phone, and it is still confined to the kidney, meaning it hasn’t spread to nearby lymph nodes or other organs.
Doctors further split this up into two categories:
T1a: (T stands for tumor, 1 stands for the stage): A T1a stage means the tumor is smaller than 4 cm (1.6 inches), or no longer than a ping pong ball.
T1b: The tumor is 4 to 7 cm (1.6 to 2.8 inches), or no bigger than a tennis ball on its longest side.
In general, if you are diagnosed at stage I kidney cancer, your prognosis is encouraging. The five-year survival rate, or chance of living at least five years after a diagnosis, is around 95%. Keep in mind these numbers are estimates and can’t predict any individual outcome.
Stage II Kidney Cancer
If you’ve reached stage 2 of this disease, you have a mid-sized tumor in the kidney. At this point, tumors measure more than 7 cm (2.8 inches), taking up a good chunk of the kidney, but still don’t extend beyond the organ (your kidney is usually 10 to 11 cm long).
This stage, too, is broken into two groups:
T2a: This means the tumor is between 7 to 10 cm (2.8 to 3.9 inches), or about the length of a standard Band-Aid
T2b: Tumor is larger than 10 cm (3.9 inches), or longer than a typical chocolate bar.
For tumors of this size, the type of cancer you have makes a big difference with how the disease behaves. For instance, clear cell renal cell carcinoma (the most common type of kidney cancer), spreads more quickly than other kidney cancers.
So by the time a tumor reaches 7 cm, cancer cells have often spread outside the kidney (and would no longer be considered stage 2 cancer). But for people with papillary or chromophobe renal cell carcinoma (about 10% and 5% percent of renal cell carcinomas, respectively), it’s more common that tumors can reach this size before cancer cells have spread to different tissues.
The five-year relative survival rate for stage 2 kidney cancer is between 80% and 90%.
Stage III Kidney Cancer
Once a tumor expands to neighboring lymph nodes or invades nearby tissue, it’s considered stage 3 cancer, regardless of its size. Crucially, these tumors haven’t yet permeated an envelope of tissue covering the kidney called Gerota’s fascia. The tumors may also have crept into veins stemming from the kidney. This is a bit of a tricky concept, since your veins are sort of a back door out of the kidney, but tumors here are still considered stage 3 cancer because technically they haven't spread to other organs or past the outer kidney covering.
This stage has three further groupings:
T3a: Tumors have spread into the veins inside the kidney or a layer of fat surrounding the kidney (but remain inside the Gerota’s fascia).
T3b: At this point, a tumor has reached the body’s largest vein, called the inferior vena cava, but hasn’t made it to the diaphragm, a thin muscle below your chest.
T3c: These tumors have grown into that major vein, the vena cava, and traveled up inside the vein above the diaphragm, approaching the heart; or a tumor has infiltrated the wall of the vena cava.
When cancer has reached this stage, it’s still possible for doctors to remove the tumor in some cases, but it’s a lot trickier, and often tumors will come back. Because of this, the five-year relative survival rate for stage 3 kidney cancer is close to 60%.
Stage IV Kidney Cancer
Because kidney cancer can have almost no symptoms for many people, between some 20% and 30% of patients with renal cell carcinoma won’t be diagnosed until their disease has reached stage 4 kidney cancer.
At this point, a tumor has spread to the adrenal gland on the same side of the tumor (a small cap over the kidney that makes hormones) or beyond the kidney to other organs (this is known as metastasis). Unlike some other types of cancer, renal cell carcinoma tumors can show up anywhere in the body, but will often spread to the lungs, liver, bones, or brain. When tumors have reached these different regions, it’s common for patients to have corresponding symptoms—trouble breathing, bone pain, or neurologic issues.
Treatments options for metastatic kidney cancer are rapidly progressing. Twenty years ago, many people with this diagnosis lived for only 10 to 15 months. Today, most live for over two years. Still, the current data suggests the five-year relative survival rates range from 13% to 20%.
Deep breath. The survival stats for stage 4 kidney cancer are undeniably low. (On the other hand, if you have stage 1 or stage 2 kidney cancer, your chances of shaking this disease are surprisingly good.) The important thing to know, if you’ve received a metastatic kidney cancer diagnosis, is that new drug therapies are increasing your odds every day. Researchers and clinicians are actively exploring new drug therapies, and some metastatic patients have remained disease-free after treatment. So while stage 4 isn’t the diagnosis you want to hear, knowing where you stand gives you a starting point as you head into treatment.
Kidney Cancer Stats: American Cancer Society. (2020). “Key Statistics About Kidney Cancer.” cancer.org/cancer/kidney-cancer/about/key-statistics.html
Kidney Cancer Evaluation and Staging: Journal of the National Comprehensive Cancer Network. (2017). “Kidney Cancer: Clinical Practice Guidelines in Oncology.” jnccn.org/view/journals/jnccn/15/6/article-p804.xml
Stages: American Cancer Society. (2020). “Kidney Cancer Stages.” cancer.org/cancer/kidney-cancer/detection-diagnosis-staging/staging.html
Detailed Stages: Histopathology. (2019). “Renal Cell Carcinoma Staging: Pitfalls, Challenges, and Updates.” ncbi.nlm.nih.gov/pubmed/30565307
Number of Patients Diagnosed at Each Stage: Abdominal Radiology. (2016). “Renal Cell Carcinoma: Staging and Surveillance.” Renal cell carcinoma: staging and surveillance
Stages and Five-Year Survival Rates: British Medical Journal. (2014). “Renal Cell Carcinoma.” ncbi.nlm.nih.gov/pmc/articles/PMC4707715/
The TNM Staging System: American Society of Clinical Oncology. (2019). “Kidney Cancer: Stages.” cancer.net/cancer-types/kidney-cancer/stages