title: Prognostic value of the lymph node ratio after resection of periampullary carcinomas.
abstract: BACKGROUND
  Data have indicated that the lymph node ratio (LNR) may be a better prognostic indicator than lymph node status in pancreatic cancer.
  
  
  OBJECTIVE
  To analyse the value of the LNR in patients undergoing resection for periampullary carcinomas.
  
  
  METHODS
  A cut off value of 0.2 was assigned to the LNR in accordance with published studies. The impact of histopathological factors including a LNR was analysed using Kaplan-Meier and Cox regression methods.
  
  
  RESULTS
  In total, 551 patients undergoing a resection (January 2000 to December 2010) were analysed. The median lymph node yield was 15, and 198 (34%) patients had a LNR > 0.2. In patients with a LNR of > 0.2, the median overall survival (OS) was 18 versus 33 months in patients with an LNR < 0.2 (P < 0.001). Univariate analysis demonstrated a LNR > 0.2, T and N stage, vascular or perineural invasion, grade and resection margin status to be significantly associated with OS. On multivariate analysis, only a LNR > 0.2, vascular or perineural invasion and margin positivity remained significant. In N1 disease, a LNR was able to distinguish survival in patients with a similar lymph node burden, and correlated with more aggressive tumour pathological variables.
  
  
  CONCLUSIONS
  A LNR > 0.2, and not lymph note status, is an independent prognostic factor for OS indicating the LNR should be utilized in outcome stratification.
authors.affiliation: Department of Pancreatic Surgery, St James's University Hospital, Leeds, UK.
authors.forename: Shahid G
authors.initials: SG
authors.lastname: Farid
authors.forename: Gavin A
authors.initials: GA
authors.lastname: Falk
authors.forename: Daniel
authors.initials: D
authors.lastname: Joyce
authors.forename: Sricharan
authors.initials: S
authors.lastname: Chalikonda
authors.forename: R Matthew
authors.initials: RM
authors.lastname: Walsh
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Smith
authors.forename: Gareth
authors.initials: G
authors.lastname: Morris-Stiff
mesh_terms: D000368:Aged; D014670:Ampulla of Vater / Q000473:pathology / Q000601:surgery*; D002277:Carcinoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D016009:Chi-Square Distribution; D003138:Common Bile Duct Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D004739:England; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision / Q000009:adverse effects / Q000401:mortality; D008198:Lymph Nodes / Q000473:pathology / Q000601:surgery*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018365:Neoplasm, Residual; D009820:Ohio; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D016577:Pancreaticoduodenectomy / Q000009:adverse effects / Q000401:mortality; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome