title: Results of European pooled analysis of IORT-containing multimodality treatment for locally advanced rectal cancer: adjuvant chemotherapy prevents local recurrence rather than distant metastases.
abstract: BACKGROUND
  The purpose of this study is to analyze the pooled results of multimodality treatment of locally advanced rectal cancer (LARC) in four major treatment centers with particular expertise in intraoperative radiotherapy (IORT).
  
  
  METHODS
  A total of 605 patients with LARC who underwent multimodality treatment up to 2005 were studied. The basic treatment principle was preoperative (chemo)radiotherapy, intended radical surgery, IORT and elective adjuvant chemotherapy (aCT). In uni- and multivariate analyses, risk factors for local recurrence (LR), distant metastases (DM) and overall survival (OS) were studied.
  
  
  RESULTS
  Chemoradiotherapy lead to more downstaging and complete remissions than radiotherapy alone (P < 0.001). In all, 42% of the patients received aCT, independent of tumor-node-metastasis stage or radicality of the resection. LR rate, DM rate and OS were 12.0%, 29.2% and 67.1%, respectively. Risk factors associated with LR were no downstaging, lymph node (LN) positivity, margin involvement and no postoperative chemotherapy. Male gender, preoperatively staged T4 disease, no downstaging, LN positivity and margin involvement were associated with a higher risk for DM. A risk model was created to determine a prognostic index for individual patients with LARC.
  
  
  CONCLUSIONS
  Overall oncological results after multimodality treatment of LARC are promising. Adding aCT to the treatment can possibly improve LR rates.
authors.affiliation: Department of Surgery, Catharina Hospital, Eindhoven, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Kusters
authors.affiliation: Department of Radiation Oncology, Università Cattolica S. Cuore, Rome, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Valentini
authors.affiliation: Department of Oncology, Hospital General Universitario Gregorio Marañon, Madrid, Spain.
authors.forename: F A
authors.initials: FA
authors.lastname: Calvo
authors.affiliation: Department of Radiation Oncology, University of Heidelberg, Heidelberg, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Krempien
authors.affiliation: Department of Surgery, Catharina Hospital, Eindhoven, The Netherlands.
authors.forename: G A
authors.initials: GA
authors.lastname: Nieuwenhuijzen
authors.affiliation: Department of Radiotherapy, Catharina Hospital, Eindhoven, The Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Martijn
authors.affiliation: Department of Surgery, Università Cattolica S. Cuore, Rome, Italy.
authors.forename: G B
authors.initials: GB
authors.lastname: Doglietto
authors.affiliation: Department of General Surgery, Hospital Gregorio Marañón, Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Del Valle
authors.affiliation: Department of Radiation Oncology, University of Heidelberg, Heidelberg, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Roeder
authors.affiliation: Department of Surgery, University of Heidelberg, Heidelberg, Germany.
authors.forename: M W
authors.initials: MW
authors.lastname: Buchler
authors.affiliation: Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: C J H
authors.initials: CJH
authors.lastname: van de Velde
authors.affiliation: Department of Surgery, Catharina Hospital, Eindhoven, The Netherlands. Electronic address: harm.rutten@cze.nl.
authors.forename: H J T
authors.initials: HJT
authors.lastname: Rutten
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000175:diagnosis / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D013505:Digestive System Surgical Procedures / Q000379:methods*; D018450:Disease Progression; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control*; D011379:Prognosis; D011878:Radiotherapy / Q000379:methods*; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D016019:Survival Analysis