title: The abdominoperineal resection itself is associated with an adverse outcome: the European experience based on a pooled analysis of five European randomised clinical trials on rectal cancer.
abstract: OBJECTIVE
  The aim of this study is to identify factors associated with the decision to perform an abdominoperineal resection (APR) and to assess if these factors or the surgical procedure itself is associated with circumferential resection margin (CRM) involvement, local recurrence (LR), overall survival (OS) and cancer-specific survival (CSS).
  
  
  METHODS
  The Swedish Rectal Cancer Trial (SRCT), TME trial, CAO/ARO/AIO-94 trial, EORTC 22921 trial and Polish Rectal Cancer Trial (PRCT) were pooled. A propensity score was calculated, which indicated the predicted probability of undergoing an APR given gender, age and distance, and used in the multivariate analyses.
  
  
  RESULTS
  An APR procedure was associated with an increased risk of CRM involvement [odd ratio (OR) 2.52, p<0.001], increased LR rate [hazard ratio (HR) 1.53, p=0.001] and decreased CSS rate (HR 1.31, p=0.002), whereas the propensity score was not.
  
  
  CONCLUSIONS
  The results suggest that the APR procedure itself is a significant predictor for non-radical resections and increased risk of LR and death due to cancer for patients with advanced rectal cancer.
authors.affiliation: Department of Surgery, Leiden University Medical Center, K6-R, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
authors.forename: Marcel
authors.initials: M
authors.lastname: den Dulk
authors.affiliation: Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Hein
authors.initials: H
authors.lastname: Putter
authors.affiliation: Department of Statistics, EORTC Headquarters, Brussels, Belgium.
authors.forename: Laurence
authors.initials: L
authors.lastname: Collette
authors.affiliation: Department of Radiotherapy, NKI-AVL, Amsterdam, The Netherlands.
authors.forename: Corrie A M
authors.initials: CAM
authors.lastname: Marijnen
authors.affiliation: Department of Surgery, Uppsala University Hospital, Uppsala, Sweden.
authors.forename: Joakim
authors.initials: J
authors.lastname: Folkesson
authors.affiliation: Department of Radiation Therapy, Besançon University Hospital, Besançon, France.
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Bosset
authors.affiliation: Department of Radiation Therapy, University of Frankfurt, Frankfurt am Main, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Rödel
authors.affiliation: Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Bujko
authors.affiliation: Department of Surgery, Uppsala University Hospital, Uppsala, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Påhlman
authors.affiliation: Department of Surgery, Leiden University Medical Center, K6-R, P.O. Box 9600, 2300 RC Leiden, The Netherlands. Electronic address: c.j.h.van_de_velde@lumc.nl.
authors.forename: Cornelis J H
authors.initials: CJH
authors.lastname: van de Velde
mesh_terms: D000005:Abdomen / Q000473:pathology / Q000601:surgery*; D000230:Adenocarcinoma / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D000368:Aged; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D018579:Patient Selection; D010502:Perineum / Q000473:pathology / Q000601:surgery*; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D012004:Rectal Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D012007:Rectum / Q000601:surgery; D012306:Risk; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome