Treating kidney cancer without surgery

By Nicole Ferrara • March 26, 2024

Estimated reading time: 6 minutes

By Nicole Brudos Ferrara

Kidney cancer treatment often begins with surgery to remove the cancer, with the goal of preserving normal kidney function when possible. For people with smaller tumors diagnosed at stage 1 or 2, when they are still confined to the kidney, surgery is the most common treatment.

Surgery to remove all or part of a kidney is called a nephrectomy. While such procedures are often safe, all surgery comes with risks. If you have other medical issues that place you at high risk for surgical complications or if your cancer has spread beyond the kidney (metastasized to stage 3 or 4), your care team may consider other treatment options.

"People commonly won't be candidates for surgery if they can't tolerate general anesthesia well, have a high bleeding risk, a high risk of infection, a history of poor healing, or if they've had multiple prior abdominal surgeries," says Anne Rajkumar, M.D., a radiation oncologist at Mayo Clinic Comprehensive Cancer Center. Risks and complications depend on the type of surgery, reasons for surgery, overall health and many other factors.

Research has shown that less invasive treatment options provide excellent outcomes for people with kidney cancer, says Dr. Rajkumar. These include ablation procedures, including radiation therapy, as well as systemic therapies. Here's an overview of those options:

Ablation procedures for kidney cancer

Dr. Rajkumar says ablation procedures are commonly considered as an alternative to surgery for people with small kidney tumors. Ablation is a minimally invasive procedure used to destroy (ablate) abnormal tissue.

Radiologists, doctors trained in imaging, perform two kinds of ablation procedures to treat kidney cancer:

Cryoablation uses cold to treat cancer. During cryoablation, a radiologist inserts a thin needle called a cryoprobe through the skin directly into the tumor. A gas is pumped into the cryoprobe to freeze the tissue. Then, the tissue is allowed to thaw. The freezing and thawing process is repeated several times.
Radiofrequency ablation uses electrical energy and heat to destroy cancer cells. A radiologist uses imaging to guide a thin needle through the skin or an incision and into the cancer tissue. High-frequency energy passes through the needle and causes the surrounding tissue to heat up, killing nearby cells.

There are even less invasive options if people aren't candidates for cryoablation or radiofrequency ablation.

Radiation therapy is an ablation procedure performed by radiation oncologists trained in the diagnosis and treatment of cancer — oncology — as well as how to use guided radiation to treat cancer. "Radiation oncologists often see the highest risk kidney cancer patients for whom other techniques aren’t an option because they use sedation and needles that can pose healing and bleeding risks," says Dr. Rajkumar. "Or sometimes the tumor is of a size or in a location that is harder to treat with more invasive ablative techniques."

Radiation therapy uses high-powered energy beams from X-rays and protons to kill cancer cells. Radiation causes some cancer cells to die immediately after treatment, but most die or become incapacitated because of the radiation-induced damage to the cancer cell's chromosomes and DNA.

Recent research has shown that stereotactic body radiotherapy (SBRT), also called stereotactic ablative radiotherapy (SABR), can be an effective treatment for people whose cancer remains in the kidney (localized). This type of radiation therapy uses highly focused X-ray radiation beams to send high doses of radiation to the area to be treated. This results in the least damage to the area's healthy tissues. "We can get exceptional local control of the cancer without causing kidney damage," says Dr. Rajkumar.

Research has also demonstrated that proton SBRT can be an effective treatment for people with kidney cancer. Proton therapy radiates fewer normal, healthy cells than X-ray radiation therapy. Proton therapy uses the positively charged particles in an atom (protons) that release their energy within the target: the tumor. "With proton radiation therapy, less radiation dose goes to good kidney tissue. This makes it less likely that the treatment will affect the patient's kidney function," says Dr. Rajkumar.

Dr. Rajkumar says adaptive radiation therapy can also help preserve kidney function. When practicing adaptive radiation therapy, radiation oncologists change a patient's radiation treatment plan before each treatment to adapt it to changes in the patient's body. "If we have a large kidney cancer and there's a loop of bowel right next to it, that loop of bowel may be far away the next day. Adaptive radiation therapy allows us to optimize a radiation plan in real time, which spares healthy kidney tissue from toxicity and helps us treat as much of the tumor as possible," she says.

Treating kidney cancer that has spread.

"For people with a larger number of tumors, the treatment is generally systemic therapy with immunotherapy or a type of targeted therapy called a tyrosine kinase inhibitor," says Dr. Rajkumar. Systemic therapies are drugs that are taken orally or intravenously to treat cancer throughout the body.

Systemic therapies for kidney cancer include:

Targeted therapy: Targeted drug treatments focus on specific abnormalities in cancer cells. By blocking these abnormalities, targeted drug treatments can cause cancer cells to die.
Immunotherapy: Immunotherapy uses your immune system to fight cancer. Your body's disease-fighting immune system may not attack your cancer because the cancer cells produce proteins that help them hide from the immune system cells. Immunotherapy works by interfering with this process.

When a person isn't at high risk for complications from surgery, surgeons may perform a procedure called a cytoreductive nephrectomy to remove the primary kidney tumor. This might be done before systemic therapy or after a person has taken systemic therapy and tests have shown that tumors are shrinking. "Studies have shown there is a survival benefit to getting rid of the primary kidney tumor that is sending cancer cells throughout the body," says Dr. Rajkumar.

However, removing a primary kidney tumor is a complex surgery, even for people who aren't at high risk for complications. "People need time to heal. And when a person is healing — a month, maybe two — they can't get systemic therapy," says Dr. Rajkumar.

Radiation therapy may offer an alternative to surgery. Mayo Clinic is participating in a nationwide study that randomly assigns people who aren't candidates for cytoreductive nephrectomy to either systemic therapy alone or systemic therapy with radiation therapy. "The question of the trial is: In these patients with a large number of metastases, is there an additional benefit to treating the primary kidney tumor with radiation therapy?" says Dr. Rajkumar.

Ablation may also be an option for metastatic kidney cancer. "If people have a limited number of tumors, then we try to ablate all of their disease, which has been shown in studies to result in overall improved time off systemic therapy and good survival rates," says Dr. Rajkumar.