title: Risk factors associated with poor lymph node harvest after colon cancer surgery in a national cohort.
abstract: OBJECTIVE
  Evaluation of ≥ 12 lymph nodes (LNs) is recommended after surgery for colon cancer. A harvest of ≤ 8 is considered poor, but few reports have evaluated risk factors associated with a poor harvest. This aims of this study were to analyse the clinical, surgical and pathological factors associated with poor LN harvest (LNH), the total number of examined nodes and the effect of LN number on stage.
  
  
  METHODS
  All patients reported to the Norwegian Colorectal Cancer Registry during 2007 and 2008 who underwent curative resection for Stage I-III colon cancer were studied. Risk factors for poor LNH and the proportion of Stage III disease were analysed by univariate and multivariate analyses.
  
  
  RESULTS
  A total of 2879 patients were included in the study. The median LNH was 14. Overall, 69.9% had ≥ 12 lymph nodes and 14.4% had ≤ 8 LN (poor harvest). Multivariate analysis showed that male sex, age > 75 years, sigmoid tumours, pT category 1-2, failure to use the pathology report template and distance of ≤ 5 cm from the bowel resection margin were all independent factors for poor LNH. Age < 65 years, pT category 3-4, and poor tumour differentiation were independent predictors of Stage III disease. An increased LNH did not increase the proportion of patients identified as being LN positive at the ≤ 8, 9-11 and ≥ 12 LN levels.
  
  
  CONCLUSIONS
  Adequate LNH was achieved in the majority of curative colon cancer resections in this national cohort. Elderly, male patients with sigmoid cancers, and a short distal margin were at increased risk of a poor LNH.
authors.affiliation: Department of Surgery, Stavanger University Hospital, Stavanger, Norway. nedreboe@me.com
authors.forename: B S
authors.initials: BS
authors.lastname: Nedrebø
authors.forename: K
authors.initials: K
authors.lastname: Søreide
authors.forename: A
authors.initials: A
authors.lastname: Nesbakken
authors.forename: M T
authors.initials: MT
authors.lastname: Eriksen
authors.forename: J A
authors.initials: JA
authors.lastname: Søreide
authors.forename: H
authors.initials: H
authors.lastname: Kørner
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D016015:Logistic Models; D008197:Lymph Node Excision / Q000592:standards / Q000706:statistics & numerical data*; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D009664:Norway; D012307:Risk Factors; D012737:Sex Factors; D012811:Sigmoid Neoplasms / Q000473:pathology / Q000601:surgery