When using radiation therapy to treat prostate cancer, the goal is to focus the radiation "beam" only on the prostate and to avoid the surrounding structures, and thus minimize the likelihood of erectile dysfunction. The bladder, rectum and nerves responsible for erection all lay next to the prostate along with the muscle that is responsible for the conscious control of our urine (that is, the muscle that prevents us from leaking urine after the prostate is treated). The side effects that come after radiation treatment are due to the radiation's effect on these adjacent structures. These effects may come over time as the radiation affects the cells' ability to propagate and live normally and provide the functional role that is required of them. The cells lining the bladder or rectum may become less healthy and may cause bleeding or ulceration.
Technology, however, has greatly improved over time. The ability of the radiation oncologist to focus the "beam" on only the prostate is much better than it was ten years ago. One example of these techniques is called "intensity modulated radiation therapy." Treatment is given over the course of several weeks, and it does not require an anesthesia. Computerized tomography or "CAT" scans are used to pinpoint the prostate in the pelvis, allowing proper focus on the gland and seminal vesicles (the seminal vesicles are storage "sacs" for semen that lay next to the prostate. They are included in the treatment of prostate cancer, both with surgery and radiation). Focusing the therapy on only the prostate and seminal vesicles limits the side effects. The negative effects on erectile function appear to be less than surgery; however, the results vary between treatment centers as do results with prostatectomy (previously discussed).
Published On: October 22, 2007