Radiation Therapy for Kidney Cancer

Radiation therapy uses high-energy X-rays or other forms of radiation to damage the DNA of cancer cells, preventing them from growing and dividing. Although surgery remains the primary treatment for many localized kidney tumors, radiation therapy can play an important role for selected patients, including those who cannot undergo an operation and those whose cancer has spread to other parts of the body.

Historically, renal cell carcinoma—the most common type of kidney cancer—was considered relatively resistant to conventional radiation doses. However, today’s advanced treatment techniques can deliver much higher doses of radiation with considerable precision. For a patient with localized kidney cancer who is not a surgical candidate, stereotactic body radiation therapy (SBRT) may be used with the goal of controlling or eliminating the tumor. Radiation therapy also can help control a metastatic tumor and relieve symptoms, such as pain or bleeding.

At Moffitt Cancer Center, our radiation oncologists work closely with urologic surgeons, medical oncologists, medical physicists and other specialists to determine when radiation therapy may be beneficial. When developing a treatment plan, our multispecialty team considers factors such as the location and extent of the cancer and the patient’s kidney function and overall health.

Goals of radiation therapy for kidney cancer

The role of radiation therapy for kidney cancer can vary according to the stage, size and location of the tumor, as well as the patient’s overall health, kidney function and other therapies. Before treatment begins, the healthcare team will explain whether radiation therapy is intended to control or eliminate a localized tumor, treat an area where cancer has spread or relieve symptoms.

Radiation therapy for localized kidney cancer

A surgical procedure such as a partial or radical nephrectomy is the standard treatment for many localized kidney tumors. However, surgical treatment is not appropriate in every case. Some patients may have another medical condition that could make an operation unsafe, while others may have a tumor that is technically difficult to remove or prefer a nonsurgical approach.

In a carefully selected patient, highly focused SBRT may be used as a primary treatment for a localized kidney tumor. SBRT delivers a large dose of radiation to a precisely defined target while minimizing exposure to the remaining kidney and nearby organs. Treatment may be delivered with the goal of achieving long-term local tumor control.

Radiation therapy is not routinely given before or after surgery for kidney cancer. However, it may be considered in select circumstances based on the stage and location of the tumor and other individual clinical factors.

Radiation therapy for metastatic kidney cancer

Radiation therapy can also target kidney cancer that has spread to another part of the body. For example, radiation may be directed to a metastatic tumor in the brain, spine, bones or another location.

Depending on the extent of the cancer and the overall treatment strategy, highly focused radiation may be used to control a limited number of metastatic tumors. For more widespread disease, radiation therapy is often used to relieve symptoms caused by a specific tumor while systemic treatments, such as immunotherapy or targeted therapy, address cancer elsewhere in the body.

Radiation therapy for kidney cancer symptom relief

When kidney cancer is advanced, radiation treatment can shrink or control a tumor that is causing pain, bleeding or pressure on nearby structures. For example, radiation therapy may help relieve pain from a bone metastasis or reduce symptoms caused by a tumor pressing on the spinal cord or another critical structure.

In this setting, the goal of radiation therapy is to reduce symptoms rather than eliminate the cancer. Treatment may help relieve discomfort, preserve function and improve quality of life and may sometimes be completed in a relatively small number of treatment sessions.

Types of radiation therapy for kidney cancer

Moffitt uses advanced radiation technologies to tailor treatment to the size, shape and location of a tumor while limiting radiation exposure to surrounding healthy tissues. The most appropriate technique depends on whether radiation is being directed to the kidney itself or to an area where kidney cancer has spread.

External beam radiation therapy (EBRT) for kidney cancer

External beam radiation therapy delivers radiation from a machine outside the body. A linear accelerator generates radiation beams and directs them toward the tumor from carefully calculated angles.

Several techniques can enhance the precision of EBRT:

• Intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) – IMRT and VMAT allow the intensity and shape of the radiation beams to be adjusted around the contours of a tumor. This can reduce unnecessary radiation exposure to nearby healthy tissues.
• Stereotactic body radiation therapy – SBRT delivers highly focused, high-dose radiation to a tumor outside the brain, usually in fewer sessions than conventional radiation therapy. This approach can be particularly useful for selected patients with localized kidney tumors and certain metastatic tumors.
• Stereotactic radiosurgery (SRS) – SRS uses similar principles to deliver highly precise radiation to tumors in the brain and may be considered when kidney cancer has metastasized there.
• Image-guided radiation therapy (IGRT) – IGRT uses imaging before and, in some cases, during treatment to confirm the position of the tumor. This is especially important for kidney tumors because the kidneys can move as the patient breathes.
• Motion-management techniques – These techniques can account for movement during respiration and help the radiation team maintain accurate targeting throughout treatment.

Internal radiation therapy (brachytherapy) for kidney cancer

Brachytherapy places a small source of radioactive material directly inside or near a tumor rather than directing radiation from outside the body. Although Moffitt offers brachytherapy for several cancers, this approach is used much less frequently for kidney cancer than external beam techniques, such as SBRT.

If brachytherapy is being considered for a particular patient, the radiation oncology team can explain why it may be appropriate and how it compares with other available treatment options.

What to expect before, during and after radiation therapy for kidney cancer

Radiation therapy will be carefully planned before the first treatment is delivered. Knowing what happens at each stage can make the process more predictable and help the patient feel better prepared for treatment.

Preparing for radiation therapy for kidney cancer

Radiation treatment planning begins with a consultation with a radiation oncologist, who will review the patient’s imaging studies, pathology results, kidney function, previous treatments and overall health. Other members of the radiation oncology team may include medical physicists, dosimetrists, radiation therapists, nurses and other specialists.

If radiation therapy is recommended, the patient will attend a planning appointment known as simulation. During this session, computed tomography (CT) imaging will typically be used to create a detailed three-dimensional map of the treatment area. Magnetic resonance imaging (MRI) or other imaging modalities may be incorporated if additional detail is needed.

The patient will be placed in the same position that will be used for each radiation treatment session. A customized cushion or another immobilization device may be created to help the patient maintain the proper position. Small skin marks or tiny permanent tattoos may also be used to help the radiation therapists align the patient accurately.

After the simulation, the radiation oncologist, medical physicist and dosimetrist will use specialized computer software to determine the radiation dose and design the beam arrangement. The objective is to deliver the prescribed dose to the tumor while limiting exposure to healthy kidney tissue and nearby organs such as the bowel, liver and spinal cord.

What to expect on radiation treatment days

On each treatment day, the radiation therapist will position the patient on the treatment table using the measurements and positioning devices established during the simulation. Imaging may be performed before the radiation is delivered to verify that the tumor and surrounding anatomy are properly aligned.

External radiation therapy itself is painless. The patient will not feel the radiation as it is delivered. The treatment team will leave the room while the radiation beam is on, but the therapist will be able to see the patient through video monitoring and communicate through an intercom throughout the session.

The total appointment time will be longer than the radiation delivery itself because careful positioning and imaging are essential to ensure accurate treatment. The amount of time required can vary depending on the radiation technique and treatment site.

Radiation treatment schedule

The radiation treatment schedule is individualized. Conventional external beam radiation therapy may be delivered over multiple sessions, while SBRT generally delivers larger doses during a much shorter course, sometimes in only a few treatments.

The patient will be evaluated regularly during radiation therapy so the healthcare team can monitor the treatment response, identify side effects and provide supportive care as needed. Follow-up after treatment may include imaging, laboratory testing and kidney function assessments, depending on the location and purpose of the radiation therapy.

Possible side effects of radiation therapy for kidney cancer

Radiation therapy is a local treatment, so its side effects are strongly influenced by the part of the body being treated. A patient receiving radiation to a kidney tumor, for instance, may experience different effects than a patient receiving radiation for a metastatic tumor in the brain or bone.

Many short-term side effects develop gradually during treatment and improve after radiation therapy ends. The radiation oncology team can often recommend medications, dietary adjustments and other supportive measures to prevent or reduce troublesome symptoms.

Common side effects and proactive management

Possible side effects of radiation directed to a kidney tumor or nearby area include:

• Fatigue – Tiredness may develop or increase as treatment progresses. Maintaining good nutrition, getting adequate rest and engaging in light physical activity as tolerated can help the patient manage fatigue.
• Nausea or decreased appetite – Radiation delivered to the abdomen can sometimes affect the stomach or nearby digestive structures. Antinausea medication and nutritional strategies can help manage these symptoms.
• Diarrhea or other bowel changes – If part of the bowel is within or near the treatment field, irritation may cause temporary gastrointestinal symptoms. Dietary adjustments and medications may provide relief.
• Skin changes – The skin in the treatment area may become mildly red, dry, itchy or sensitive. The radiation oncology team can recommend appropriate skin care products and advise the patient about protecting the area from irritation and sun exposure.
• Urinary symptoms – Depending on the treatment location, some patients may experience urinary discomfort or changes in urinary habits. The healthcare team can evaluate these symptoms and recommend appropriate management.

Side effects can differ considerably when radiation is directed to a metastatic site. The radiation oncology team will explain which side effects are most likely based on the specific area being treated.

Possible long-term and late-onset side effects

Modern radiation planning is designed to minimize radiation exposure to healthy organs, but some side effects can develop months or even years after treatment. The likelihood can vary based on the treatment site, radiation dose, amount of healthy tissue exposed and other individual factors.

For radiation directed to a kidney tumor, an important consideration is preserving kidney function. Treatment planning will carefully limit radiation exposure to healthy kidney tissue whenever possible, and kidney function may be monitored with blood tests during long-term follow-up. Less commonly, radiation therapy can affect other nearby organs and tissues.

Radiation therapy can also cause long-term changes in tissues within the treatment field, such as fibrosis or scarring. Follow-up care will allow the healthcare team to monitor for late effects and recommend treatment or rehabilitation if a problem develops.

Managing daily life during radiation therapy for kidney cancer

Many patients can continue much of their usual routine during radiation therapy, although individual experiences may vary. The following strategies can help support physical and emotional well-being throughout treatment:

• Protect the treated skin – Wash the area gently and avoid applying lotions, creams, adhesive products or other substances unless they have been approved by the radiation oncology team. Protecting treated skin from direct sunlight and excessive heat can also help prevent irritation.
• Prioritize nutrition and hydration – Adequate intake of calories, protein and fluids can help support the body during treatment. If nausea, appetite changes or other symptoms make eating difficult, Moffitt’s oncology dietitians can recommend strategies tailored to the patient’s nutritional needs.
• Remain physically active when possible – Gentle activities such as light walking can help maintain strength and may reduce fatigue. Activity levels can be adjusted from day to day according to the patient’s energy and the healthcare team’s recommendations.
• Ask for help with symptoms and emotional concerns – Moffitt offers supportive services that can help the patient manage the physical and emotional effects of cancer treatment, including counseling, integrative medicine, nutritional support and symptom management.

Radiation therapy clinical trials for kidney cancer at Moffitt Cancer Center 

As a research-focused cancer center, Moffitt continually evaluates new approaches to cancer treatment, including advances in radiation oncology. Clinical trials can help researchers determine how radiation therapy can be used more effectively, precisely or conveniently for kidney cancer.

Current radiation therapy research may evaluate new treatment technologies, combinations of radiation therapy with systemic treatments and approaches that deliver highly focused radiation in fewer treatment sessions. Some studies may also investigate ways to improve tumor control while further limiting radiation exposure to healthy kidney tissue and other nearby organs.

Participation in a clinical trial is voluntary, and not every study is appropriate for every patient. A specialist at Moffitt can discuss available kidney cancer clinical trials and explain how an investigational approach compares with established treatment options.

Frequently asked questions (FAQs) about radiation therapy for kidney cancer 

A patient considering radiation therapy for kidney cancer may have questions about why it is recommended and what treatment will involve. The following answers address several common concerns:

Is radiation therapy an effective treatment for renal cell carcinoma?

Yes, radiation therapy can be effective for selected patients with kidney cancer. Although renal cell carcinoma has historically been considered relatively resistant to conventional radiation doses, highly focused techniques such as stereotactic body radiation therapy can deliver larger doses directly to the tumor and achieve high rates of local cancer control. SBRT may be considered for some patients with localized kidney cancer who cannot undergo surgery and can also be used to treat certain metastatic tumors.

How is stereotactic body radiation therapy used to treat kidney tumors?

SBRT uses sophisticated imaging and treatment planning to direct multiple highly focused radiation beams at a kidney tumor. Because the radiation is delivered with considerable precision, a high dose can be concentrated within the tumor while limiting exposure to the healthy portion of the kidney and nearby organs. Treatment is typically completed in fewer sessions than conventional radiation therapy.

Can radiation therapy cure kidney cancer?

Radiation therapy is not the primary curative treatment for most kidney cancers because surgery remains standard for many patients with localized disease. However, SBRT may be used as a potentially curative treatment for a carefully selected patient with localized kidney cancer who cannot undergo surgery. In other circumstances, radiation therapy may be used to achieve durable control of a tumor without necessarily being expected to cure the cancer. Whether radiation therapy can potentially eliminate a particular tumor will depend on its size and location, the cancer’s stage, the patient’s health and other clinical factors.

Does radiation therapy for kidney cancer hurt?

No. External beam radiation therapy is painless while it is being delivered, much like having an X-ray. Some patients may develop side effects during or after a course of treatment, but the radiation oncology team can provide supportive care to help manage them.

How do physicians protect the healthy part of the kidney during radiation therapy?

Radiation oncologists use detailed imaging and computerized treatment planning to define the tumor and nearby normal structures. Advanced techniques such as SBRT, IMRT and IGRT can conform the radiation closely to the contours of the tumor, while imaging guidance and motion management help account for changes in the kidney’s position during breathing. The treatment plan will also incorporate dose limits designed to protect functioning kidney tissue and other nearby organs.

Will the patient be radioactive after external beam radiation therapy?

No. External beam radiation passes through the body during treatment and does not remain there. A patient who receives EBRT will not be radioactive afterward and will not need to avoid contact with other people because of the radiation treatment.

The Moffitt Cancer Center approach to radiation therapy for kidney cancer

Radiation therapy for kidney cancer requires careful consideration of the tumor, the patient’s kidney function and the other treatment options available. At Moffitt, the specialists in our Urologic Oncology and Radiation Oncology programs work together to determine whether radiation therapy should be part of an individualized treatment strategy.

Moffitt’s radiation oncologists have access to sophisticated treatment-planning and radiation-delivery technologies, including SBRT, IMRT, IGRT, VMAT, MRI-guided radiation therapy and advanced motion-management techniques. Moffitt’s Radiation Oncology Program is accredited by the American College of Radiology, reflecting our adherence to rigorous standards for radiation oncology practice, safety and quality.

As a National Cancer Institute (NCI)-designated Comprehensive Cancer Center, Moffitt also conducts extensive cancer research and clinical trials. This combination of subspecialized expertise, advanced technology and research allows the multispecialty team to evaluate established and emerging treatment approaches for patients with localized and advanced kidney cancer.

To learn more about radiation therapy for kidney cancer, you can request an appointment with a specialist in Moffitt’s Urologic Oncology Program by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.