Radiation Therapy for Prostate Cancer

Page Contents

Radiation therapy (also called radiotherapy) uses high-energy beams or subatomic particles to damage the DNA inside prostate cancer cells. After enough damage, the cells cannot multiply, and they die. 

You might have internal radiation therapy, external-beam radiation therapy (EBRT) or both. Internal radiation therapy means a radioactive substance is put inside your body so it can emit radiation from within. EBRT means radiation comes from a source outside your body. The radiation is delivered either as photons (such as X-rays or gamma rays) or subatomic particles (tiny particles that are smaller than atoms, such as electrons or protons).

Prostate Cancer Care Tailored to You

You and your family are our top priority. At Fred Hutch Cancer Center, we offer comprehensive and compassionate care — personalized to you. You'll have access to the latest treatment options, clinical trials and supportive care services. 

Request an Appointment

How Radiation Therapy Can Treat Prostate Cancer 

Internal Radiation Therapy

For prostate cancer, internal radiation therapy typically means putting radioactive “seeds,” or pellets, in the prostate (brachytherapy). A urologist implants the seeds, which send out low doses of radiation for weeks or months. This method is generally used in men with the earlier stages of localized cancer. 

If you have advanced prostate cancer, your care team may recommend another type of internal radiation therapy, called molecular therapy or nuclear medicine therapy.

These therapies are drugs (sometimes called radiopharmaceuticals) that deliver small “packages” of radiation to cancer cells anywhere in your body. They include lutetium-177 dotatate, lutetium-177 vipivotide tetraxetan and radium-223 dichloride. We offer all of these molecular therapies at the Sloan Clinic.

Each of these medicines is given by infusion. Liquid medicine is put into a vein through an intravenous (IV) line. This is done on a schedule in repeating cycles. The schedule depends on the therapy. For example, Lu-177 vipivotide tetraxetan is given every six weeks for up to six cycles. Learn more about molecular therapies. 

 

External-Beam Radiation Therapy

EBRT can be used to cure localized prostate cancers or help relieve symptoms of cancer that has spread. Based on your exact needs, your radiation oncologist will likely recommend one of these forms of EBRT:

  • Proton therapy, an advanced form of radiation treatment. Physicians can focus proton beams precisely on tumors, limiting radiation to nearby healthy tissues, like the bladder or rectum. So, we use proton therapy most often for anatomically complex tumors. Learn more about proton therapy for prostate cancer.
  • IMRT, or intensity modulated radiation therapy. This uses a computer-controlled linear accelerator to move around you to deliver radiation. We can shape the beams and aim them at your tumor from several angles. We can also adjust the intensity of the beams so less radiation reaches sensitive normal tissue. 
  • VMAT, or volumetric modulated arc therapy. This is a type of IMRT. Similar to IMRT, we vary the beam shape and intensity to contour the radiation to your tumor. But VMAT is delivered in one continuous arc of the linear accelerator around your body. This maximizes the contouring and typically takes even less time than IMRT.
Amir Iravani
Dr. Amir Iravani, Fred Hutch radiologist

Why Choose Fred Hutch for Radiation Therapy for Prostate Cancer

Fred Hutch uses the latest technology to provide the most precise radiation therapy possible for prostate cancer. We offer a wide range of radiation therapy options and match the best approach to your diagnosis.

Our radiation oncology experts take great care to align your body for EBRT. This helps ensure the radiation is focused on your tumor cells with the least chance of affecting healthy cells nearby.

Typically, physicians place markers into your prostate before EBRT to align you with the radiation beam for your daily treatment sessions. Different markers can be used, including gold markers that are imaged each day by computed tomography (CT) scanning built into the linear accelerator.

Another marker is known as the Calypso System. It allows electromagnetic tracking of your tumor’s position without needing daily CT scans. If your prostate moves during treatment, the radiation can be adjusted in real time. So, the tumor receives the correct amount and nearby organs don’t receive radiation not meant for them. Fred Hutch radiation oncologists were involved in developing the Calypso System, also known as GPS for the Body.

In some cases, our physicians inject gel between the prostate and rectum before radiation treatment starts. This makes space between the rectum and prostate to protect the rectum from radiation.

Request an Appointment

Radiation Therapy for Prostate Cancer FAQ 

The way to give radiation therapy depends on the type of therapy you’re having. For brachytherapy, you’ll have a procedure where a surgeon will place radioactive seeds in your body. For molecular therapy, you’ll get an intravenous (IV) drug infused into your bloodstream. For EBRT, you’ll go to a specialized treatment center or part of the clinic where a machine will send an invisible high-energy beam to the target area inside your body. The experience is similar to getting an X-ray.

Radiation therapy is an option for men with various stages of prostate cancer. 

  • If you have localized prostate cancer, your doctor will probably give you a choice of treating your disease with either radiation or surgery. Cure rates are about the same for both treatments, and studies haven’t clearly proved one is better than the other. 
  • If your cancer returns, you may receive radiation therapy after surgery.
  • If you have advanced prostate cancer, you may have radiation therapy along with other therapies.
  • If cancer has spread elsewhere in your body, such as to your bones, radiation may help relieve pain at these sites.

The risks and side effects depend on the type of radiation therapy. In general, radiation therapy may cause some body-wide side effects, like fatigue or lower levels of blood cells. Other effects will be more focused around the area being treated. Radiation to the pelvic area for prostate cancer may cause problems with the bladder, bowel, erections or fertility.

Your Fred Hutch care team will explain what to expect. We’ll talk with you before radiation therapy about the risks and side effects that might happen with the kind of treatment you’re receiving.

Your care team at Fred Hutch is here to help you prevent or prepare for side effects and to relieve any side effects you have. The most important step you can take is to speak up and let your team know what you’re feeling. We’ve helped many patients and families through this process and know ways to ease your experience.

We can give you practical tips for dealing with whatever you’re going through, like how to cope with fatigue or how to improve bladder control. For some side effects, like diarrhea, your care team can recommend over-the-counter medicine or give you a prescription to help. Our supportive care providers can help too. For example, you can meet with a Fred Hutch social worker or psychologist to discuss concerns related to relationships, body image, intimacy and sexuality.

Your radiation oncology team will design your treatment schedule, including the number of treatments you receive. It depends largely on the type of radiation therapy best for you.

For brachytherapy, you might have seeds that stay in place forever (even though they stop giving off radiation after a while). Or, you might have seeds briefly inserted and then removed, through very small tubes, over a few days to a few weeks. For molecular therapy, you will probably get a dose every six to eight weeks for four to six cycles. For EBRT, patients usually get treatment Monday through Friday for five to eight weeks.

We’ll let you know what to expect based on your treatment plan. Here are general guidelines.

If you’re having the type of brachytherapy where the seeds are inserted and then removed, the seeds are in place for 10 to 20 minutes at a time. This is done in an operating room with anesthesia, so the whole session will be longer.

If you’re having EBRT, the treatment itself takes only a few minutes. Appointments are usually about 20 to 30 minutes, including time to set up the equipment for your session and align your body.

If you’re having molecular therapy, the infusion takes about 20 to 35 minutes, based on the drug. Your whole visit may be two to five hours.

The best way to treat prostate cancer depends on many factors, like the stage and the risk that the cancer will spread. Some men have a combination of treatments that work in different ways.

Radiation therapy may be effective for you if:

  • Cancer is only in your prostate. In this case, your care team may give you a choice between radiation or surgery. Both can be effective. 
  • Your cancer returns. Radiation therapy may be helpful after surgery.
  • You have advanced prostate cancer. For advanced disease, you may have radiation along with other treatments.
  • Cancer has spread to other parts of your body. Radiation may help relieve pain at these sites, such as your bones.