title: Metastatic lymph node ratio as an independent prognostic variable in colorectal cancer: study of 113 patients.
abstract: BACKGROUND
  In patients with colorectal cancer, involvement of the lymph nodes is one of the most important prognostic factors. The aim of this study was to determine the independent prognostic value of the lymph node ratio (LNR), that is the relationship between the involved and examined lymph nodes, in patients with colorectal cancer.
  
  
  METHODS
  Included in the study were 113 patients with colorectal adenocarcinoma. The patients were divided into three groups according to the proportion of involved lymph nodes: LNR-0, when there was no lymph node involvement; LNR-1, when there was involvement of up to 20% of the examined lymph nodes, and LNR-2, when there was involvement of 21% or more of the examined nodes. The relationship between lymph node ratio, the number of lymph nodes removed, and the number of lymph nodes involved by cancer was determined. The 5-year survival was evaluated using the Kaplan-Meier test.
  
  
  RESULTS
  There was a significant difference in 5-year overall between patients in the different LNR groups (p=0.009). Patients in the LNR-0 group had a 5-year overall survival greater than 80%, while those in the LNR-1 and LNR-2 groups had 5-year overall survival rates less than 60% and 40%, respectively. Multivariate analysis demonstrated that the LNR is an independent prognostic variable in 5-year overall survival (p=0.009).
  
  
  CONCLUSIONS
  The results showed that the LNR can be considered an independent prognostic variable in overall survival of patients with colorectal cancer.
authors.affiliation: São Francisco University Medical School, São Paulo, Brazil.
authors.forename: D G
authors.initials: DG
authors.lastname: Priolli
authors.forename: I Aparecida
authors.initials: IA
authors.lastname: Cardinalli
authors.forename: J Aires
authors.initials: JA
authors.lastname: Pereira
authors.forename: C Helaehil
authors.initials: CH
authors.lastname: Alfredo
authors.forename: N Fontana
authors.initials: NF
authors.lastname: Margarido
authors.forename: C A Real
authors.initials: CA
authors.lastname: Martinez
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality* / Q000556:secondary* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D015996:Survival Rate