External Beam Radiation Therapy

External beam radiation therapy involves a series of daily treatments to accurately deliver radiation to the prostate. Radiation therapy can be as effective as the surgery to treat prostate cancer. Before treatment begins, your radiation oncologist will develop a treatment plan using information from your biopsy, imaging and physical exam. A CT scan will done in the position you will be treated, often with a supportive device to keep you comfortably in the same position for treatment. This is often called a pre-treatment mapping (scan).

Before starting the daily treatment, you will be asked to have a full bladder to minimize side effects. Your treatment plan will include the prostate, but can sometimes include the seminal vesicles (glands on the back of the prostate) and lymph nodes. With CT scans, 3-D targets of the prostate and normal tissues are created. These treatment plans focus radiation beams on the prostate while limiting radiation to healthy tissues around it such as the bladder and rectum. Intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT) are treatment approaches that allow the radiation beams to treat the cancer and lessen the risks of side effects.

External beam radiation therapy can be delivered using a variety of techniques. With all external beam therapy, treatment is delivered in a series of daily sessions, five days a week, for several weeks. Each treatment is non-invasive, painless and similar to a long X-ray; you hear noise but will feel nothing at the time of treatment.

Hormone Therapy

Depending on the stage of your cancer, you may benefit from adding hormone therapy to radiation. Hormone therapy lowers testosterone production. Testosterone is a hormone that plays an important role in prostate cancer progression. It may be used together with radiation therapy, before radiation to shrink the tumor and also after radiation has been completed. The length of time you will receive hormone therapy depends on the stage of your cancer. Ask your doctor for more information.