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...

