title: Oncologically safe distal resection margins in rectal cancer patients treated with chemoradiotherapy.
abstract: BACKGROUND
  Although current guidelines recommend distal resection margins (DRM) of 2-5 cm in rectal cancer operation, smaller margins may be safe. We therefore assessed the impact of distal margins on outcomes in patients with rectal cancer treated with neoadjuvant chemoradiotherapy (CRT) followed by radical resection or resection followed by adjuvant CRT.
  
  
  METHODS
  This study involved 376 patients who underwent sphincter-saving resection for rectal adenocarcinoma and pre- or postoperative CRT between 2000 and 2006. DRMs were measured on pinned fixed specimens. We excluded patients who did not complete planned CRT and those with stage IV disease. A retrospective cross-sectional analysis was performed.
  
  
  RESULTS
  No significant differences in local recurrence (9.8 versus 7.3%; P = 0.324) and systemic recurrence (16.4 versus 18.7%; P = 0.731) were observed in patients with DRMs of ≤5 and >5 mm, respectively. Moreover, in each DRM category, there were no differences in local and systemic recurrence rates between patients who received pre- or postoperative CRT. DRM did not affect overall survival (P = 0.880) or 5-year survival rate (80.3 versus76.8%; P = 0.340).
  
  
  CONCLUSIONS
  A distal margin of at least 5 mm with negative resection margin on frozen section does not reduce oncological safety in rectal cancer patients who receive pre- or postoperative CRT.
authors.affiliation: Department of Surgery, Institute of Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, 86 Asanbyeongwon-gil, Songpa-gu, Seoul, 138-736, Republic of Korea.
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Kwak
authors.forename: Chan Wook
authors.initials: CW
authors.lastname: Kim
authors.forename: Seok-Byung
authors.initials: SB
authors.lastname: Lim
authors.forename: Chang Sik
authors.initials: CS
authors.lastname: Yu
authors.forename: Tae Won
authors.initials: TW
authors.lastname: Kim
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Se Jin
authors.initials: SJ
authors.lastname: Jang
authors.forename: Jin Cheon
authors.initials: JC
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000601:surgery* / Q000628:therapy; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D000069287:Capecitabine; D059186:Chemoradiotherapy, Adjuvant; D003430:Cross-Sectional Studies; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000031:analogs & derivatives; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery* / Q000628:therapy; D012007:Rectum / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D003841:Deoxycytidine; D000069287:Capecitabine; D002955:Leucovorin; D005472:Fluorouracil