title: Lymph node ratio is an independent prognostic factor in patients with rectal cancer treated with preoperative chemoradiotherapy and curative resection.
abstract: OBJECTIVE
  To evaluate the prognostic effect of lymph node ratio (LNR) in patients with locally advanced rectal cancer who were treated with curative resection after preoperative chemoradiotherapy (CRT).
  
  
  METHODS
  Between October 2001 and December 2007, 519 patients who had undergone curative resection of primary rectal cancer after preoperative CRT were enrolled. Of these, 154 patients were positive for lymph node (LN) metastasis and were divided into three groups according to the LNR (≤ 0.15 [n=80], 0.16-0.3 [n=44], >0.3 [n=30]) to evaluate the prognostic effect on overall survival (OS) and disease-free survival (DFS).
  
  
  RESULTS
  LNR (≤ 0.15, 0.16-0.3, and >0.3) was significantly associated with 5-year OS (90.3%, 75.1%, and 45.1%; p<0.001) and DFS (66.7%, 55.8%, and 21.9%; p<0.001) rates. In a multivariate analysis, LNR (≤ 0.15, 0.16-0.3, and >0.3) was a significant independent prognostic factor for OS (hazard ratios [HRs], 1, 3.609, and 8.197; p<0.001) and DFS (HRs, 1, 1.699, and 3.960; p<0.001). LNR had a prognostic impact on OS and DFS in patients with <12 harvested LNs, as well as in those with ≥ 12 harvested LNs (p<0.05).
  
  
  CONCLUSIONS
  LNR was a significant independent prognostic predictor for OS and DFS in patients with locally advanced rectal cancer who were treated with curative resection after preoperative CRT.
authors.affiliation: Center for Colorectal Cancer, National Cancer Center, Goyang, Republic of Korea.
authors.forename: S D
authors.initials: SD
authors.lastname: Lee
authors.forename: T H
authors.initials: TH
authors.lastname: Kim
authors.forename: D Y
authors.initials: DY
authors.lastname: Kim
authors.forename: J Y
authors.initials: JY
authors.lastname: Baek
authors.forename: S Y
authors.initials: SY
authors.lastname: Kim
authors.forename: H J
authors.initials: HJ
authors.lastname: Chang
authors.forename: S C
authors.initials: SC
authors.lastname: Park
authors.forename: J W
authors.initials: JW
authors.lastname: Park
authors.forename: J H
authors.initials: JH
authors.lastname: Oh
authors.forename: K H
authors.initials: KH
authors.lastname: Jung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059186:Chemoradiotherapy, Adjuvant; D015986:Confounding Factors, Epidemiologic; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020360:Neoadjuvant Therapy / Q000379:methods*; D011237:Predictive Value of Tests; D011379:Prognosis; D012004:Rectal Neoplasms / Q000473:pathology* / Q000601:surgery / Q000628:therapy*; D056910:Republic of Korea; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis