A 72-year-old man comes to the physician for a follow-up visit. Three months ago, he was diagnosed with localized prostate cancer with no evidence of metastatic disease. He was treated with definitive external beam radiation therapy. The patient completed his treatment 2 weeks ago. He now complains of pelvic discomfort and increased urinary frequency. These began at the end of his radiation treatment but have improved partially since treatment was completed.
Vital signs are within normal limits. Examination shows a normal-appearing external anorectal area. The abdomen is soft and bowel sounds are normal.
Urinalysis is normal. Laboratory results are as follows:

This patient is at the greatest risk for which of the following long-term complications?

Question

A 72-year-old man comes to the physician for a follow-up visit.  Three months ago, he was diagnosed with localized prostate cancer with no evidence of metastatic disease.  He was treated with definitive external beam radiation therapy.  The patient completed his treatment 2 weeks ago.  He now complains of pelvic discomfort and increased urinary frequency.  These began at the end of his radiation treatment but have improved partially since treatment was completed.
Vital signs are within normal limits.  Examination shows a normal-appearing external anorectal area.  The abdomen is soft and bowel sounds are normal.
Urinalysis is normal.  Laboratory results are as follows:

This patient is at the greatest risk for which of the following long-term complications?

Quizplus · Accepted Answer

Sexual dysfunction is the most common long-term side effect from radiation treatment for localized prostate cancer. Up to 45% of patients become impotent after therapy, and the frequency increases with time. The risk increases further if androgen deprivation therapy is added to the radiation treatment. The risk of impotence is reduced by avoiding radiation to penile structures. Phosphodiesterase inhibitors (eg, sildenafil) may be effective in improving symptoms, unlike sexual dysfunction from surgery, which is often secondary to physical nerve damage. (Choice A) Acute gastrointestinal side effects from radiation treatment are common and appear in up to 30% of patients. These include enteritis or proctitis and present clinically as frequent defecation, rectal bleeding, or abdominal cramping. Symptoms resolve a few weeks after radiation completion. Long-term side effects include fecal incontinence, strictures, and ulcerations; estimates of risk vary from 4%-5% up to 20% of patients. (Choice B) Radiation injures the microcirculation of bone. This results in weakened bone architecture and risk of insufficiency fractures. The most commonly affected bones include the sacrum and pubis, but these fractures are relatively uncommon in prostate cancer treatment. (Choice C) Retrospective studies show an increased risk of secondary malignancies following external beam radiation. Exact risk estimates are difficult as many of these studies do not account for radiation dose or other important factors, such as smoking. The most common secondary malignancies include bladder and rectal cancers. (Choice E) Urinary frequency and dysuria occur in up to 50% of patients during treatment with external beam radiation, but symptoms usually resolve within a few weeks after therapy completion. Long-term side effects are uncommon and may include strictures, bladder contractures, and cystitis. Educational objective: Sexual dysfunction is the most common long-term adverse effect of external beam radiation for prostate cancer. The risk depends on the radiation technique and radiation field. The risk increases further if androgen deprivation therapy is added to the radiation treatment. __________ References: Health-related quality of life 2 years after treatment with radical prostatectomy, prostate brachytherapy, or external beam radiotherapy in patients with clinically localized prostate cancer. (http://www.ncbi.nlm.nih.gov/pubmed/18325680)

A 72-Year-Old Man Comes to the Physician for a Follow-Up