Let's Talk About Kidney Cancer

Whether you’ve just been diagnosed or have recurrent kidney cancer, you’re probably nervous, full of questions, and scared. That’s normal, and everyone featured on HealthCentral with a chronic illness felt just like you do now. But we’re here for you with all the critical information to help you not just manage—but thrive. We’re sure you’ve got a lot of questions...and we’re here to answer them.

What Is Kidney Cancer?

Let’s start with the basics. Your kidneys are two potato-shaped organs that sit behind your belly on either side of the spine. They filter your blood—straining out salt, water, and other chemicals—and turn the waste into pee.

This blood-cleaning action takes place in tiny pipes called tubules inside each kidney, and that’s where the trouble with cancer usually pops up. In about nine out of 10 kidney cancer patients, the cancer begins when a mass forms in these blood-filtering tubes.

Not all tumors that grow in your kidneys are cancerous, or spread throughout the body. And some cancers grow slowly, only a couple millimeters each year, or no bigger than a few grains of sand. Others, though, can quickly swell and spread to distant organs. Depending on a tumor’s size and appearance, and your underlying health, your healthcare team can assess what sort of treatment is needed.

What Causes Kidney Cancer?

We don’t know the full story of what causes kidney cancer, but we understand a few pieces of the puzzle, especially for more common forms of the disease.

In most cases, kidney cancer begins when there are mutations in certain genes that normally keep cell division in check. When this system isn’t working properly, new cells grow at abnormal rates and can amass into tumors, which can then grow and spread. For example, people with clear cell renal cell carcinoma often have a mutation that causes extra blood vessels to grow inside the kidney.

Most kidney cancer patients acquire these mutations over their lifetime, meaning they’re born with perfectly healthy genes controlling cell division, but as they age, a cell’s genetic code changes. When the cell reproduces, that quirk in the genetic code spreads. Notably, these changes usually occur in conjunction with other factors before cancer shows up.

Other people inherit certain conditions from their parents that increase their risk of developing various types of kidney cancer. Many of these people will have tumors in other organs in their body and are more likely to be diagnosed with kidney cancer in their younger years. Here are a few of those inherited disorders:

• Von Hippel-Lindau disease
• Hereditary papillary renal carcinoma
• Birt Hogg-Dubé (BHD)
• Hereditary leiomyoma (HLRCC)
• Succinate dehydrogenase deficiency
• Tuberous sclerosis
• PTEN hamartoma tumor syndrome (including Cowden syndrome)

If you have kidney cancer, ask your provider if you should consider genetic counseling, particularly if you’re diagnosed before you’re 47, have tumors on both kidneys, or if you have a family history of kidney cancer. This will determine if you have one of these genetic conditions that could raise the risk of developing cancer for other family members. Or, if you have already been diagnosed with one of these conditions, talk with your doc about your increased risk for kidney cancer.

Who Gets Kidney Cancer?

Cancerous growths can invade kidneys of people at any age, who are otherwise healthy, but some folks have a greater chance of developing kidney cancer than others. Here are a few risk factors for the most common types of kidney cancer:

• Gender: Men make up more than 60% of kidney cancer patients.
• Age: Most people are diagnosed as older adults, between the ages of 55 and 74.
• Smoking: Men who smoke are about 50% more likely to develop kidney cancer; women have close to a 20% increased risk from smoking. Scientists don’t understand exactly how smoking spurs cancer, but they do know that the risk of cancer drops the longer you stop.
• Obesity: People who are obese are 20% to 30% more likely to develop kidney cancer. Research to understand this connection is ongoing.
• High blood pressure: This can double the risk of kidney cancer, according to a number of studies.
• Family history: About 5% of patients have other family members with kidney cancer or certain inherited conditions that put them at higher risk.
• Kidney disease: People living with chronic kidney disease and those on long-term dialysis (when a machine filters your blood) have a greater risk of developing kidney cancer.
• Environmental exposures: Working with certain chemicals including trichloroethylene (often used as a solvent to remove grease), asbestos, benzene, benzidine, cadmium, herbicides, and vinyl chloride increases the risk of developing kidney cancer.

It’s important to know, though, that while checking the box for one or all of the above factors can increase your odds of getting kidney cancer, for most of the 70,000 or so people in the U.S. diagnosed each year, there is no single cause, so far as we know—other than bad luck.

What Are the Symptoms of Kidney Cancer?

Kidney cancer can be frustratingly sneaky. The majority of people don’t have any symptoms when they get a diagnosis. Instead, most learn of a mass on their kidney when they’re seeing their doctor for an unrelated issue that requires an imaging procedure. If doctors see something suspicious they can follow up with a CT scan or an MRI to get a better look at the kidney.

People often don’t experience symptoms until the cancer has advanced, although that’s not always the case. For those with symptoms (about a third of patients at diagnosis), here’s what can show up:

Related to your kidneys:

• Pain in your low back, often on one side
• Blood in your pee
• A lump around your low rib cage
• Swelling in the scrotum (varicocele)

Your whole body:

• Weight loss
• Fevers and night sweats
• Tiredness
• Low red blood cell count
• High blood pressure

The Most Common Types of Kidney Cancer

There are more than a dozen types of kidney cancer, and knowing what type you have is important to figuring out what treatments will work best for you. Your cancer type will also help predict how the disease might progress.

In all likelihood, if you are diagnosed with kidney cancer, it’s probably going to fall under the category known as renal cell carcinoma. The vast majority of kidney cancers belong to this category, meaning the cancer shows up in the main chunk of the kidney, where the organ filters blood.

Within renal cell carcinomas, there are sub-types of cancers that differ depending on what the tumor cells look like under a microscope. Here are the three most common types of renal cell carcinomas:

Clear Cell

• Accounts for between 70 to 80% of renal cell carcinomas.
• Aptly named, these tumor cells look transparent when magnified. Because it’s the most common type, clear cell renal cell carcinoma (RCC) is one of the best understood kidney cancers and treatment options are fairly well established.
• This type of kidney cancer can come back years or even decades after treatment.
• If clear cell RCC spreads outside the kidneys, it can pop up anywhere in the body, but it is most likely to be found in the lungs, liver, brain, or bones.

Papillary

• Makes up 10% to 20% of renal cell carcinomas.
• These cells look pink underneath a microscope and form long, finger-like shapes inside a tumor. There are two types of papillary RCC: Type 1 tends to be slow-growing and confined to the kidney. Type 2 is often more aggressive and likely to spread to other organs.

Chromophone

• Responsible for 5% of renal cell carcinomas.
• The cells in chromophone RCC are also pale, but larger than clear cell RCC.
• Tumors are often slow-growing and don’t typically spread outside the kidney.

Rare Renal Cell Carcinomas

In addition to the common types of renal cell carcinomas, there are multiple rare types of the disease that each make up less than 1% of all kidney cancers. If you have a rare form of kidney cancer, your doctor will likely suggest seeing a specialist to get the best possible treatment.

• Acquired Cystic Disease–Associated RCC: This rare cancer exclusively shows up in patients with end-stage kidney disease.
• Collecting Duct Tumors: This aggressive disease is usually diagnosed in young adults at an advanced stage of cancer, typically with poor prognosis
• Mucinous Tubular and Spindle Cell Carcinoma: An extremely rare form, this cancer is more often found in women, and is typically slow-growing.
• Neuroblastoma-Associated RCC: This disease is only found in survivors of certain childhood cancers that affect immature nerve cells or the adrenal glands.
• Renal Medullary Carcinoma: An extremely aggressive cancer, RMC is found in patients with sickle cell trait and related diseases, and often affects kids and young adults.

Other Types of Kidney Cancers

Not all kidney cancers are renal cell carcinomas. These are a few other forms the disease can take.

Urothelial Carcinoma

This disease accounts for 5% to 10% of adult kidney cancers. Tumors grow in the part of the kidney that stores pee before it heads to the bladder. Even though these tumors are found in the kidney, they’re not considered a renal cell carcinoma and are instead treated as bladder cancer.

Renal Sarcomas

This cancer starts or spreads to the blood vessels inside the kidney and is usually aggressive; it’s often diagnosed in later stages of the disease.

Wilms’ Tumor

This disease is almost always found in young kids, typically ages 3 to 4, and usually appears without symptoms. It’s the most common type of kidney cancer in kids, but luckily the disease can be fully treated.

Benign Growths

Sometimes, masses grow in the kidneys but don’t spread to other parts of the body. Roughly one in five small kidney tumors (under 1.5 inches) that surgeons remove aren’t cancerous, however these can still cause symptoms. These are two types of benign tumors:

• Angiomyolipoma: More common in women, these tumors can develop on their own or in people with tuberous sclerosis.
• Oncocytoma: This tumor is more often seen in men. It isn't cancerous, but can be associated with other cancers in the kidney.

Disease Stages and Outcomes

The progression of kidney cancer is measured by the size and spread of tumors. How far along a person’s cancer has advanced, the type of cancer, response to treatment, and a person's underlying health are all important pieces of information to give context to someone’s likelihood of survival.

The term survival is sort of scary, we know. It’s your life, after all. But keep in mind that relative survival statistics broadly compare the survival of people diagnosed with cancer to those in the general population—they can’t predict what will happen to an individual patient. What’s more, kidney cancer treatments are rapidly progressing. Depending on the type of cancer, the survival rate today may look more optimistic than just a few years ago, which is what the most current stats are based on.

Here’s a look at the stages of progression for kidney cancer, and what they mean for your prognosis:

Stage I: A small tumor that’s only in the kidney

A: The tumor is smaller than 4 cm (1.5 inches) or no bigger than a ping pong ball

B: The tumor is 4 - 7 cm, or smaller than a baseball

Stage II: A tumor larger than 7 cm (2.8 inches), still confined to the kidney

The five-year relative survival rates for local kidney cancer (stages I and II) is 92.6%, meaning more than nine out of 10 people with the disease are still alive five years after diagnosis.

Stage III: A tumor of any size that’s spread to nearby lymph nodes, grown into major veins stemming from the kidney, or has invaded nearby tissue. The five-year relative survival rate for when kidney cancer has spread to nearby lymph nodes (mostly stage III) is 70%.

Stage IV: The cancer has either spread beyond the kidney to other organs (often the lungs, liver, bones, and brain), or the tumor has grown beyond the lining of the kidney (but not necessarily spread to other organs). Nearly one in five patients are diagnosed at this stage. The five-year relative survival rate for kidney cancer that has spread to other organs (mostly stage IV) is 13%.

How Do Doctors Treat Kidney Cancer?

The best way to treat kidney cancer depends on the type of disease, how far it’s progressed, and your age and overall health. Generally, people with kidney cancer have these broad treatment options:

Active Surveillance

For many people with small tumors, especially those who may be at high risk for medical procedures, a watch and wait strategy can be the best option. Your medical team will continue to take images of the tumor every few months for any signs of growth.

Thermal Ablation

If someone isn’t a good candidate for surgery and their tumor is in the right spot (often closer to the back, away from other organs) and not too big (typically under 4 cm, or 1.5 inches), a doctor might perform a less-invasive medical procedure that uses extreme cold or heat to destroy the tumor.

Known as thermal ablation, these treatments have less evidence for getting rid of a tumor for good compared to surgery, but it’s still a promising option for certain patients in early stages of the disease, and offers less risk of complications. Many doctors perform thermal ablations in an outpatient setting, using local anesthesia. Here are the two ways they zap off a tumor:

• Cryotherapy

  A needle enters the tumor and pumps in very cold gases, effectively making an ice ball that freezes the cancer cells.

• Radiofrequency ablation

  A doctor places a thin probe at the edge of a tumor to heats up the mass with high-energy radio waves.

Surgery (Nephrectomy)

When kidney cancer hasn’t spread to other organs, surgery to remove some or all of the kidney is typically standard treatment and can sometimes cure the disease completely. Even if cancer has spread outside the kidney, your doctor may suggest surgery to help manage your symptoms.

Depending on how big a tumor is and where it’s located, a surgeon might opt to remove part of the kidney (called a partial nephrectomy) or take out the entire organ (a radical nephrectomy).

Partial removal of a kidney can carry higher risks of complications and isn’t always possible, but this type of surgery has the great benefit of preserving some kidney function. There are two ways to perform these operations, again depending on the size and position of a tumor:

• Open surgery: This traditional method of surgery involves operating through one central incision. Surgeons often have an easier time manipulating tissue around a tumor with this technique.
• Minimally invasive surgery: Through several small incisions, surgeons can guide long instruments inside the body to remove the kidney, including one with a camera on its end called a laparoscope. Some specialists use robotic assistance to perform these operations. Patients typically recover from these procedures more quickly, with less pain, but they’re only appropriate for some tumors, and require extensive technical expertise.

Drug Therapy

For people with advanced kidney cancer, medications are often the best treatment option, depending on the type of cancer they have. Many new therapies have emerged in the last few years and have proven highly effective for some patients. These are the general options available, often used in combination:

• Immunotherapy (biologic therapy): This class of drugs hypes up the immune system, so the body can better fight the cancer with its own defenses. Many of those with FDA approval are most effective at treating clear cell renal cell carcinoma.

  • Often two immunotherapy drugs are paired together.
  • These drugs can trigger a wide range of side effects throughout the body due to a revved up immune system, from rashes to flu symptoms, diarrhea, and shortness of breath. Some patients experience no side effects at all.

• Targeted therapy: These medications make use of how cancer cells operate to slow their spread and limit injury to healthy cells. Most are taken as pills, and they’re sometimes paired with an immunotherapy drug, or can be taken on their own. Critically, these drugs are only effective to treat certain types of kidney cancer. These are the two main types of targeted therapy:

  • Angiogenesis inhibitors (or anti-angiogenics): These drugs block blood vessels from forming in a tumor, starving it of food.
  • Tyrosine kinase inhibitors: This class of drugs block certain proteins in cancer cells (called tyrosine kinases) that help them grow, divide, and survive.

These drugs, which are sometimes used in combination, may come with a range of side effects, including nausea, diarrhea, high blood pressure, fatigue, and other more serious symptoms.

Other Treatment Options

If the more common paths to treatment are not working, your doctor may talk to you about one of the following:

Clinical Trials

Some patients take part in research studies to test new treatments or procedures that haven’t yet been approved by the FDA. These studies can offer cutting-edge treatments, but they’re not right for everyone. Ask your doctor if you might be a good fit for any clinical trials offered by nearby hospitals or research centers.

Radiation

Although radiation isn’t a primary treatment for kidney cancer, it can be used along with other therapies to control symptoms and ease pain when cancer has spread or when surgery isn’t an option.

Chemotherapy

Unlike most other forms of cancer, kidney cancers don’t usually respond to chemotherapy. This treatment can be an option for urothelial carcinoma (when cancer forms in the part of the kidney that collects pee, treated like bladder cancer), Wilms tumor (the most common type of kidney cancer in young kids), and some rare forms of the disease.

Living With Kidney Cancer

No matter how you look at it, cancer is serious, and kidney cancer is a challenging disease to overcome. But advances in medicine give more than lip service to the idea that this is a condition that—if not curable—is at least manageable for many people. With the right healthcare team and proper treatment, there’s a very good chance you can keep on top of your disease now and in the years to come.

It helps to know you’re not in this fight alone, and these organizations are devoted to connecting patients with medical experts, quality information, and other people in the community who are dealing with kidney cancer and know exactly what you are going through:

• Kidney Cancer Association
• The Kidney Cancer Research Alliance (KCCure)
• The VHL Alliance

Use these or other organizations, family members, and friends to form your support team. Remember, being diagnosed with kidney cancer is not the beginning of the end, it’s the beginning of your first steps back to good health.