Chronic effects of pelvic radiation therapy on anorectal function.
OBJECTIVE
The long-term effect of 4,500 cGy of preoperative radiation on anorectal function has not been prospectively evaluated.


METHODS
Anal manometry was performed on 20 patients with rectal carcinoma before and four weeks after receiving 4,500 cGy of external radiotherapy. Four patients underwent proctectomies, three died, and three refused follow-up. Ten patients were available for long-term follow-up and underwent anal manometry at 14 to 42 (average, 35.5) months after initial radiotherapy.


RESULTS
No significant difference in mean maximum squeeze or resting pressures was found after radiation therapy. The sphincter profile and minimum sensory threshold were unchanged. The rectoanal inhibitory reflex was present in all patients. Nine patients reported normal anal function. One patient who was incontinent before treatment remained incontinent.


CONCLUSIONS
Preoperative radiation therapy has a minimal chronic effect on anorectal function. Incontinence after sphincter-saving operations for rectal cancer should not be attributed to preoperative radiation therapy.
Birnbaum
E H
EH
Department of Surgery, Washington University School of Medicine, St. Louis, Missouri.
Myerson
R J
RJ
Fry
R D
RD
Kodner
I J
IJ
Fleshman
J W
JW
D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D003131:Combined Modality Therapy; D005242:Fecal Incontinence / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D011300:Preoperative Care / Q000379:methods*; D011446:Prospective Studies; D011832:Radiation Injuries / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D011879:Radiotherapy Dosage; D012004:Rectal Neoplasms / Q000628:therapy*; D012018:Reflex; D012684:Sensory Thresholds; D016896:Treatment Outcome