title: Impact of pelvic radiotherapy on morbidity and durability of sphincter preservation after coloanal anastomosis for rectal cancers.
abstract: OBJECTIVE
  This study was designed to assess the impact of pelvic radiotherapy on the incidence of complications and colostomy-free survival of patients after a coloanal anastomosis for rectal cancer.
  
  
  METHODS
  A total of 192 patients underwent a coloanal anastomosis between 1982 and 2001: 87 patients did not receive pelvic radiotherapy; 105 patients received pelvic radiotherapy (39 preoperative and 66 postoperative). Early and late complications requiring surgical intervention and the colostomy-free survival rate were assessed by retrospective review of patient records.
  
  
  RESULTS
  After a median follow-up of 62 months, 151 patients were alive. The most frequent complication was development of an anastomotic stricture (5-year rate of a stricture, 16 percent; 95 percent confidence interval, 10-21). Patients receiving pelvic radiotherapy had a higher rate of complications other than anastomotic strictures, including fecal incontinence, fistulas, abscesses, and bowel obstructions compared with patients not receiving pelvic radiotherapy (5-year rate: 20 percent (95 percent confidence interval, 10-29) vs. 5 percent (95 percent confidence interval, 0-10); P = 0.001). Patients receiving pelvic radiotherapy had a lower colostomy-free survival than did patients not receiving pelvic radiotherapy (5-year colostomy-free rate: 72 percent (95 percent confidence interval, 62-84) vs. 92 percent (95 percent confidence interval, 86-98); P < 0.001). There was no significant difference in the colostomy-free survival of patients receiving preoperative and postoperative pelvic radiotherapy.
  
  
  CONCLUSIONS
  After coloanal anastomosis, a significant number of patients will have complications requiring surgical intervention, and some will require a permanent colostomy. Pelvic radiotherapy, whether it is administered preoperatively or postoperatively, significantly increases the need for a permanent colostomy.
authors.affiliation: Division of Colon and Rectal Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Imran
authors.initials: I
authors.lastname: Hassan
authors.forename: David W
authors.initials: DW
authors.lastname: Larson
authors.forename: Bruce G
authors.initials: BG
authors.lastname: Wolff
authors.forename: Robert R
authors.initials: RR
authors.lastname: Cima
authors.forename: Heidi K
authors.initials: HK
authors.lastname: Chua
authors.forename: Dieter
authors.initials: D
authors.lastname: Hahnloser
authors.forename: Megan M
authors.initials: MM
authors.lastname: O'Byrne
authors.forename: Dirk R
authors.initials: DR
authors.lastname: Larson
authors.forename: John H
authors.initials: JH
authors.lastname: Pemberton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal / Q000601:surgery; D000714:Anastomosis, Surgical; D016009:Chi-Square Distribution; D003106:Colon / Q000601:surgery; D003125:Colostomy / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012004:Rectal Neoplasms / Q000532:radiotherapy*; D012007:Rectum / Q000503:physiopathology; D012307:Risk Factors; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D016896:Treatment Outcome