Physiologic changes of the anorectum after pelvic radiotherapy for the treatment of prostate and bladder cancer.
BACKGROUND
The effect of pelvic radiotherapy on anorectal function is not clearly documented and is investigated in this prospective study.


METHODS
Thirty-one males (median age, 70 years) with carcinoma of the prostate (n = 28) and bladder (n = 3) completed proctitis/incontinence symptom score questionnaires and anorectal physiology studies before and six weeks after pelvic radiotherapy. At six months after completion of radiotherapy, 25 of these patients were studied again. The results were expressed as medians and ranges and compared by the Mann-Whitney U test (2-tailed).


RESULTS
Six weeks and six months after treatment, respectively, the proctitis symptom scores (0 (0-4) vs. 2 (0-7) (P < 0.001) vs. 2 (0-5) (P < 0.001)) and the incontinence symptom scores (0 (0-5) vs. 4 (0-11) (P < 0.001) vs. 3 (0-14) (P < 0.001)) increased. Urgency, frequency of defecation, anorectal pain, incontinence to liquid stool and to flatus, and alteration in lifestyle were significant symptoms after treatment. The following measurements decreased: anal canal resting pressure (83 (35-137) vs. 79 (26-152) (P = NS) vs. 71 (29-97) (P < 0.01) cm H2O), the squeeze increment (152 (51-135) vs. 162 (63-321) (P = NS) vs. 108 (45-296) (P < 0.042) cm H2O), and the maximum tolerated rectal volume (245 (115-450) vs. 194 (112-344) (P < 0.05) vs. 200 (109-350) (P < 0.138) ml). The rectal electrosensory threshold increased (20 (5.4-44) vs. 22 (9-50.5) (P < 0.134) vs. 31.5 (13.6-76) (P < 0.001) mA).


CONCLUSIONS
Anorectal symptoms at six weeks after pelvic radiotherapy are related to reduced rectal capacity and compounded at six months by diminished internal and external sphincter function and rectal mucosal sensitivity.
Kushwaha
Rajeev S
RS
Department of Surgery, Royal Free and University College Medical School, and dagger Meyerstein Institute of Oncology, The Middlesex Hospital, London, United Kingdom.
Hayne
Dickon
D
Vaizey
Carolynne J
CJ
Wrightham
Elisa
E
Payne
Heather
H
Boulos
Paul B
PB
D000230:Adenocarcinoma / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal / Q000503:physiopathology* / Q000528:radiation effects; D002295:Carcinoma, Transitional Cell / Q000532:radiotherapy*; D003967:Diarrhea / Q000209:etiology / Q000503:physiopathology; D005242:Fecal Incontinence / Q000209:etiology / Q000503:physiopathology; D005414:Flatulence / Q000209:etiology / Q000503:physiopathology; D005500:Follow-Up Studies; D006801:Humans; D008019:Life Style; D008297:Male; D008365:Manometry; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D011349:Proctitis / Q000209:etiology / Q000503:physiopathology; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011878:Radiotherapy / Q000009:adverse effects; D012007:Rectum / Q000503:physiopathology* / Q000528:radiation effects; D012684:Sensory Thresholds / Q000502:physiology; D011795:Surveys and Questionnaires; D001749:Urinary Bladder Neoplasms / Q000532:radiotherapy*