External beam radiotherapy, or radiation, has been utilized as one of the various treatments for localized prostate cancer. It can be used by itself or in conjunction with surgery as a therapeutic modality. However, like all medical treatments it has its own side effect profile, which must be weighed by the patient before undergoing therapy.
Urinary Incontinence
Patients often complain of incontinent urine after radiation therapy. Symptoms are primarily related to radiation-related damage of the small blood vessels that supply the bladder, bladder sphincter and urethra. Resulting weakness of the aforementioned structures can make it harder for the patient to control his flow of urine.
Urethral Stricture
Damage to the urethra, which is the tube that carries urine from the bladder to outside the body, can result in stricture formation. As a result, urine flow can become impeded, resulting in urinary retention. Over time, this can cause damage to the kidneys resulting in renal failure. Surgery is often necessary to relieve the obstruction.
Rectal Damage
Damage to the rectum and associated structures can result due to the rectum's proximity to the prostate. Proctitis, which is inflammation of the rectum, can occur with resulting symptoms such as pain, constipation, mucus discharge, and bloody stools. Irritable bowel syndrome is also one of the possible consequences of radiotherapy damage to rectal structures.
Erectile Dysfunction
After radiation therapy for prostate cancer, approximately half the patients go on to develop some degree of erectile dysfunction. The mechanism of injury is damage to blood vessels that supply the corpora cavernosa structure and the nerves that control it. Often symptoms begin roughly 12 months after therapy and younger patients with a better baseline erectile function have better outcomes in general. Patients suffering from this side effect are often prescribed medications such as sildenafil to assist with erectile and proper sexual function.
References
- "Campbell-Walsh Urology, 9th Edition"; Wein; 2007
- "Abeloff's Clinical Oncology, 4th Edition"; Abeloff; 2008
