title: Pathological response after chemoradiation for T3 rectal cancer.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of preoperative chemoradiotherapy (CRT) on nodal disease in locally advanced rectal adenocarcinoma.
  
  
  METHODS
  Thirty-two patients staged uT3N0 and 27 patients staged uT3N1 rectal adenocarcinoma who underwent pre-CRT staging using endoscopic ultrasound or rectal protocol CT were included. The median radiation dose was 50.4 Gy (range: 45-50.4 Gy) at 1.8 Gy per fraction and all patients received concurrent 5-FU or capecitabine-based chemotherapy. Low anterior resection or abdomino-perineal resection occurred at a median of 46 days (range: 27-112 days) after CRT.
  
  
  RESULTS
  Eleven of 32 uT3N0 patients (34.4%) and 13 of 26 uT3N1 patients (50.0%) had ypN+ (P = 0.29). For patients with uT3N0, 10 of 20 (50.0%) with ypT2-3 and 1 of 12 (8.3%) with ypT0-1 were ypN+ (P = 0.02). For patients with uT3N1, 12 of 20 (60.0%) with ypT2-3 and 1 of 6 (16.7%) with ypT0-1 were ypN+ (P = 0.16). Overall, the ypN+ rate was 11.1% in the ypT0-yT1 group compared with 55.0% in the ypT2-yT3 group (P = 003). Among patients with uT3N0 disease, the ypN+ rate in patients who had surgery > 46 days vs<or= 46 days was 7.1%vs 55.6% (P = 0.01) respectively. Among patients with uT3N1 disease, the ypN+ rate in patients who had surgery > 46 days vs<or= 46 days was 54.5%vs 46.7%, (P = 0.99) respectively. Overall, the ypN+ rate in patients who had surgery > 46 days vs<or= 46 days was 28.0%vs 51.5% (P = 0.11).
  
  
  CONCLUSIONS
  The risk of residual nodal disease after CRT is significant. Primary tumour response is associated with nodal response.
authors.affiliation: Department of Radiation Oncology, Stanford University Medical Center, Stanford, CA, USA.
authors.forename: S K
authors.initials: SK
authors.lastname: Chennupati
authors.forename: A
authors.initials: A
authors.lastname: Kamaya
authors.forename: G A
authors.initials: GA
authors.lastname: Fisher
authors.forename: J M
authors.initials: JM
authors.lastname: Ford
authors.forename: P
authors.initials: P
authors.lastname: Kunz
authors.forename: H
authors.initials: H
authors.lastname: Itakura
authors.forename: M L
authors.initials: ML
authors.lastname: Welton
authors.forename: A
authors.initials: A
authors.lastname: Shelton
authors.forename: J
authors.initials: J
authors.lastname: Van Dam
authors.forename: A C
authors.initials: AC
authors.lastname: Koong
authors.forename: D T
authors.initials: DT
authors.lastname: Chang
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000188:drug therapy / Q000532:radiotherapy; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D003113:Colonoscopy / Q000379:methods; D004307:Dose-Response Relationship, Radiation; D019160:Endosonography / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000532:radiotherapy; D012007:Rectum / Q000000981:diagnostic imaging / Q000473:pathology*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents