Radiation Therapy for Prostate Cancer

Radiation therapy uses energy to attack prostate cancer cells. It can sometimes cure early-stage prostate cancer, sparing patients a prostatectomy. Patients may also receive radiation after surgery to prevent the cancer from recurring. It’s often delivered over multiple treatment sessions.

Patients can be anxious at the prospect of receiving treatment with radiation. At Siteman, our radiation oncology team is a national leader at tailoring radiation therapy to each patient’s needs. Our physicians use innovative, high-tech methods to target the tumor while protecting surrounding tissues. What’s more, they will work to limit the number of radiation sessions, achieving optimum results while reducing the treatment burden on their patients.

The radiation techniques available at Siteman include:

  • External beam radiation
  • Brachytherapy
  • Proton beam therapy
  • Radium-223

What is external beam radiation therapy for prostate cancer?

External beam radiation therapy treats prostate cancer with X-ray beams from a machine. The treatment is painless and only lasts for a few minutes at a time.

Siteman radiation oncologists were among the first in the U.S. to deliver external beam radiation using Intensity-Modulated Radiation Therapy (IMRT). This technique enhances the delivery of high doses of radiation. In addition, they also use advanced-imaging methods such as MRI and PET scans – a technique known as Image-Guided Radiation Therapy (IGRT) – to focus treatment on the prostate, thereby reducing radiation delivery to the adjacent bladder and rectum.

Patients who develop a recurrence of their cancers after prior radical prostate surgery can be effectively treated with radiation therapy. If the prostate has been removed, radiation is delivered to the space where the prostate used to be.

Brachytherapy is radiation therapy that comes from a source implanted within the body. There are two different types: low-dose-rate brachytherapy and high-dose-rate brachytherapy.

Low-dose-rate brachytherapy

In low-dose-rate brachytherapy, a number of tiny, radioactive seeds are placed in the prostate. These seeds emit a steady dose of radiation for several weeks, and then remain permanently – and harmlessly – in place. Siteman was the first medical center in the region to perform radioactive seed implantation for prostate cancer.

High-dose-rate brachytherapy

What is brachytherapy for prostate cancer?

In high-dose brachytherapy (HDR), a single radioactive source is temporarily placed in the prostate using catheters. Typically, the catheters are inserted in the morning in the operating room under general anesthesia, then a CT scan is obtained for treatment planning, and the 5 to 15 minute treatment takes place in the afternoon. A combination of a long-acting local anesthetic and other medications keep the patient comfortable until treatment delivery. The catheters are removed at the end of the treatment. Patients go home that day and are not radioactive.

The time and position of the radioactive source is carefully controlled to maximize the radiation dose to the prostate and minimize the dose to the urethra, rectum, and bladder.

HDR brachytherapy alone can be used to treat low-risk patients, and can be used as a boost for higher-risk patients receiving external beam radiotherapy.  In select patients, HDR brachytherapy can be used to treat failures from LDR brachytherapy or external beam radiotherapy.

Siteman is the first and only medical center in the region to perform HDR brachytherapy for prostate cancer. More than 200 patients have received the treatment since our program opened in 2014.

What is proton beam therapy for prostate cancer?

Proton beam therapy kills cancer cells with protons instead of X-ray beams. The main advantage of this treatment is that the proton beam can be adjusted to specific depths, which means that the beam can stop at its target instead of passing through the entire body.

Proton therapy can be used alone or it can be used in combination with other radiation therapies and/or hormone therapy.  Your doctor can determine if you are an appropriate candidate for proton therapy and which clinical studies are available.

ThS. Lee Kling Proton Therapy Center at the Siteman Cancer Center is the only proton therapy center located in Missouri and the surrounding region. It houses the world’s first compact proton beam accelerator. Radiation oncologists and physicists here helped evaluate the system and developed the patient protocols and quality standards for this advanced technology.

How does radium-223 treat prostate cancer?

Radium-223 is a radioactive isotope. It can treat prostate cancer that has spread to the bones. Patients receive radium-223 through an IV.

Physicians and researchers at Siteman are investigating other uses for radioactive isotopes in prostate cancer treatment. In particular, they hope to develop isotope treatments for metastatic prostate cancer that is not confined to the bone.