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The development of ED is determined by the dose of radiation (how much) and field of radiation (how wide). Doses greater than 20 Gy (2000 rads) are frequently associated with large vessel injury. Typically, patients being treated with radiation for prostate cancer are receiving in excess of 70Gy. The wider the field of radiation, the less likely the blood vessels will recover. Given that the cavernosal artery is the only artery giving rise to erection, radiation exposure to this system may severely limit blood flow into the penis. Radiation specialists have made great efforts over the last two decades to minimize the negative effects associated with rad- iation, especially with the advent of 3D conformal x-ray therapy and brachytherapy (seeds). However, some men continue to suffer from this problem. In 1997, Dr. Montorsi from Milan, Italy completed the first study looking at early postoperative preventive drug therapy for this problem. Immediate therapy after surgery, using penile injections, administered within the first two months of surgery resulted in a 67% incidence of return of a patient’s natural erections com- pared to 20% in men who had no treatment after surgery. It is concluded that these erections induced soon after surgery can protect the erection tissue itself and promote the return of a patient’s natural erections. There is a strong body of opinion that suggests that men with poor erections after radical prost- atectomy should be treated with medications to induce erections early after surgery. The same concept would apply to post radiation therapy. Important concept • Prior to undergoing therapy, patients should be counseled regarding all possible sexual dysfunctions. • Seek evaluation and treatment for erection problems within the first 2 months of the procedure. • When ED exists, commence early drug therapy to obtain 2-3 erections per week. This therapy should be continued for 18 months postoperatively to increase the chance of the return of a patient’s natural erections. Recommendation Over the last two decades, more men have been diagnosed with prostate cancer at a younger age. Prostate Cancer treat- ments often lead to Erectile Dysfunction and other Sexual Dysfunction. Hence, a discussion of this topic before under- taking such treatment becomes increasingly important. This article discusses the side effects of Erectile Dysfunction associated with two common treatments: radical prostatec- tomy and radiation therapy. Post-operative complications of RP may include: • Erectile Dysfunction • Retrograde ejaculation (although orgasm is generally preserved). • Absence of orgasm or diminished overall quality • Orgasmic pain interfering with sexual relations The causes of ED include: • Nerve injury • Artery injury • Deterioration of the erectile tissue structure and function It is known that post-RP erectile function preservation is better in younger men, men with cancer confined to the prostate, or those who have at least one nerve preserved, especially if the patient had normal erections prior to his operation. The advent of the nerve-sparing procedure, first introduced in 1982, has not proven to substantially reduce the post-operative incidence of ED. It appears that preservation of the cavernous nerves does not necessarily mean the nerve function is intact. Radiation therapy to the prostate can cause ED in three ways: • Arterial blockage can occur due to the development of a condition called endarteritis obliterans and the direct dam- age to the lining of the blood vessels. • Nerve damage may occur. It has been shown that there is a reduction in the number of erection-inducing nerves in the penis following exposure to low doses of radiation. • Fibrotic change to the erectile tissue may occur, leading to a condition called venous leak. Radiation Therapy Radical Prostatectomy (RP) Prostate Cancer Treatment and Erectile Dysfunction Los Angeles • Costa Mesa • San Diego • San Francisco • Seattle • Phoenix • Denver • Houston • Dallas • Fort Lauderdale • Orlando Tampa • Chicago • Detroit • Philadelphia • Pittsburgh • Puerto Rico • Tysons Corner • Washington D.C. • Manhattan • Long Island
