Penile rehabilitation is currently part of the armamentarium used to treat erectile dysfunction (ED) after cancer therapy and/or from venous leak. Men with prostate cancer currently live for many years after their cancer treatment, therefore penile rehabilitation, also known as an erectile function preservation program, becomes part of a survivorship program with an emphasis on quality of life.
Following surgical procedures to remove the prostate for treatment of prostate cancer, the motor nerve to the penis can become injured due to its proximity to prostate tissue. As a result of this nerve injury, messages from the brain to the penis that occur either during sleep or sexual stimulation may not reach the site of action in the penile tissues. Without erectile activity, there is lack of oxygenation in the tissues, injury to the penis smooth muscle, scarring of the erection chambers and loss of elasticity of the tunica albuguinea wall that can lead to erectile tissue scarring, endothelial damage, penile shortening and penile curvature.
The principle of penile rehabilitation is to maintain penile health through various therapeutic options by inducing erections while the nerve is healing so that the erectile tissue and tunica albuguinea will be functional once the nerve integrity returns. The nerve can take up to 18 months to heal.
Penile rehabilitation may be initiated prior to surgical intervention after the diagnosis of prostate cancer has been made. The program begins with completion of validated questionnaires, sensory neurologic, vascular, and hormonal tests, administration of oral PDE5 inhibitors at various doses and intracavernosal penile injection, all to document pre-operative function. The partner should also complete validated questionnaires and be involved in the patient’s counseling, as studies have shown that engaging the partner have helped the patient and partner obtain better overall satisfaction.
Once surgery has been performed, during the post-operative recovery usually two to four weeks after surgery, the patient undergoes repeat administration of oral PDE5 medication and repeat intracavernosal injection. Most patients will have diminished erectile function. The goal of penile rehabilitation is to maximize efforts to reach pre-operative erectile function.
There are three treatment strategies for penile rehabilitation. The first involves administration of a low dose PDE5 inhibitor on a daily basis. Studies have shown that chronic PDE5 administration improves endothelial health, helps preserve smooth muscle and reduces scarring. The second part of penile rehabilitation is use, at least three times a week, penile self-injection therapy, with the goal of obtaining an erection for approximately one hour. These provide functional erections that are not only healthy for the penis but may be used for intercourse. The last part of penile rehabilitation is use of a vacuum erection device to stretch the penis at least three times a week, for 10-15 minutes at a time, to help reduce penile shortening and curvature. No constricting penile ring is used so as not to stop blood inflow. Every few weeks during penile rehabilitation the patient may try the maximum dose of PDE5 inhibitor to check for restoration of erectile capability. Evidence supports that patients who adhere to penile rehabilitation for 18 months have better erectile function restoration than those men who are not compliant or choose not to pursue the program.
The success of this erectile function preservation program in surgical patients has resulted in its use in patients with prostate cancer undergoing radiation to the prostate, both external and interstitial, for Peyronie’s Disease patients undergoing surgical reconstruction and in aging men beginning at age 50 or at age 40 – 45 years in men with pre-existing diabetes or vascular disease.
The role of testosterone is important as an adjunct to penile rehabilitation in men with hypogonadism. Use of testosterone therapy in men with prostate cancer is highly controversial at present.