Author:Ketan K. Badani, MD
Professor of Urology, Icahn School of Medicine at Mount Sinai
Vice Chairman, Urology and Robotic Operations
Director, Comprehensive Kidney Cancer Program
The Mount Sinai Health System
What is kidney cancer?
Kidney cancer originates in the kidney, a complex, fist-sized organ. We have two kidneys, located in the middle of our back. Among several roles, their most important is filtering toxins and excess water from the blood, a process that produces urine. The most common type of kidney cancer is called renal cell carcinoma, comprising about 90 percent of all kidney cancers.
What causes kidney cancer?
We know that cancerous renal cells have a genetic mutation, but we don’t know what causes that mutation. Factors increasing one’s risk of kidney cancer include older age (the average age at diagnosis is 64), smoking, obesity, and kidney failure and dialysis. Most cases of kidney cancer are sporadic, meaning they just happen, but some are inherited, so people with a history of several family members having kidney cancer are at greater risk, as well. The hereditary form generally strikes younger patients in their 20s, 30s, or 40s.
What are the signs and symptoms of kidney cancer?
In its early stages, kidney cancer usually causes no symptoms. The main signs and symptoms of more advanced cancer include:
- Blood in the urine
- Flank pain (pain in the middle side of the back)
- A mass or lump on the side or lower back
How is the cancer found early if there are no symptoms?
Unfortunately, there is no recommended screening process for kidney cancer. Most kidney tumors are found incidentally, meaning by accident, during imaging tests (such as ultrasound or MRI) for unrelated, non-specific abdominal complaints. The good news is that most kidney cancers are found early.
Can kidney cancer be cured?
When found early, kidney tumors are highly curable. However, when kidney cancer spreads, or metastasizes, to other parts of the body, it goes from being one of the most curable types of cancer to one of the least.
How is early kidney cancer treated?
Surgical removal of the tumor is the treatment of choice for cancer that has not spread beyond the kidney. Whenever possible, depending on the tumor’s location, size, and complexity, we take out just the tumor and surrounding tissue, sparing the remaining, healthy part of the kidney. This is called partial nephrectomy.
Surgery may be performed via a large, open incision through the side (under the rib cage), or laparoscopically, in which surgical instruments–including a long tube with a video camera on the end–are inserted through several small holes to remove the tumor (or entire kidney). This minimally invasive surgery can result in a shorter hospital stay, faster recovery, and less pain after surgery. An even more advanced approach is laparoscopic, robotic-assisted surgery, in which the surgeon controls miniature instruments from a remote console, using sophisticated imaging tools for guidance.
Robotic partial nephrectomies are not only helping us save the healthy part of the kidney, but also optimize its function after surgery. In the past, while cutting out the tumor and sewing the kidney back up, we had to stop all blood flow to the kidney. This damaged the kidney, even when it was saved. Now, a new robotic technique allows us to clamp just the arteries that feed the tumor, while keeping open those that supply blood to the rest of the kidney, allowing it to maintain normal blood flow.
What about treatment for more advanced cancer?
Unfortunately, kidney cancer does not respond well to radiation treatment or traditional chemotherapy, so treatment options have been limited. However, there has been improved success with a new class of drugs called tyrosine kinase inhibitors (TKIs). These medications target a specific growth pathway used by renal cell carcinoma. There is still a role for surgery in the setting of advanced kidney cancer. Even if the cancer has metastasized, if you take out the primary tumor (which, at this point, typically means removing the entire kidney), the response to therapy is better.
Some of the most exciting research right now is being done in the area of targeted kidney cancer therapies, be it chemotherapy, immunotherapy (which uses your own immune system to fight the cancer), or tumor vaccine (which boosts the body’s ability to protect itself from cancer). For instance, at the Icahn School of Medicine at Mount Sinai, we are looking at the genetic composition of different types of renal cell tumors in the hope of identifying the most effective therapy for an individual’s particular type of kidney cancer.
What should people with an early diagnosis of kidney cancer know?
Kidney tumors grow slowly during their early stages. If you are diagnosed with early kidney cancer, be sure to take the time to learn more about the cancer, seek a second opinion, and research treatment options to understand the best approach for you. The websites of the American Cancer Society and the Kidney Cancer Association are good places to start.
Is there any way to prevent kidney cancer?
While there is no known way to prevent kidney cancer, you can take steps to keep your kidneys as healthy as possible. Doing so may lower your risk for this disease, and, if you do get kidney cancer, will help ensure the best kidney function after treatment. Everything you would do for heart health will also help keep your kidneys in shape:
- Keep your blood pressure and cholesterol in check;
- If you have diabetes, make sure to control it;
- Exercise regularly and maintain a healthy weight;
- If you smoke, quit.