title: Ratio of metastatic to resected lymph nodes enhances to predict survival in patients with stage III colorectal cancer.
abstract: BACKGROUND
  The objective of this study was to assess the value of metastatic lymph node ratio in predicting prognosis of patients with stage III colorectal cancer.
  
  
  METHODS
  From 2000 to 2005 inclusively, a total of 626 patients featuring stage III colorectal cancer underwent curative resection. These patients were stratified into LNR groups: 1 (0 < LNR ≤ 0.1); 2 (0.1 < LNR ≤ 0.25); 3 (0.25 < LNR ≤ 0.5); and 4 (LNR > 0.5). The follow-up was closed in April 2010. Kaplan-Meier survival curve and log-rank test were used to evaluate the prognostic value of LNR. A Cox regression model was used for multivariate analyses.
  
  
  RESULTS
  With a median follow-up period of 42.2 months, 5-year overall survival for groups LNR1, LNR2, LNR3, and LNR4 was 73%, 64%, 44%, and 22%, respectively. In the multivariate analysis, the LNR was an independent prognostic factor for survival (P < 0.001). LNR remained statistically significant (P < 0.001), both in patients with colon and rectum cancer regardless of the number of lymph nodes retrieved (≥12 or < 12). The survival rate of ratio group LNR1 was better than ratio group LNR4 (P < 0.001) for patients with the same IIIB or IIIC staging.
  
  
  CONCLUSIONS
  LNR is an accurate prognostic method for patients with stage III colorectal cancer. We proposed an algorithm to incorporate LNR into current AJCC staging system to form new staging.
authors.affiliation: State Key Laboratory of Oncology in South China, Guangzhou, Guangdong, China.
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Qiu
authors.forename: Li-Yi
authors.initials: LY
authors.lastname: Zhang
authors.forename: Yuan-Fang
authors.initials: YF
authors.lastname: Li
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Zhou
authors.forename: Rajiv Prasad
authors.initials: RP
authors.lastname: Keshari
authors.forename: Rui-Hua
authors.initials: RH
authors.lastname: Xu
mesh_terms: D015179:Colorectal Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; 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; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate