title: Clinicopathologic factors associated with lymph node retrieval in resectable colon cancer: a Veterans' Affairs Central Cancer Registry (VACCR) database analysis.
abstract: BACKGROUND
  A long-term determinant of survival in resectable colon cancer is the involvement of regional lymph nodes. We evaluated the clinicopathologic factors associated with lymph node retrieval.
  
  
  METHODS
  We conducted a retrospective analysis of patients with resected stage I-III colon cancer in the Veteran's Affairs Central Cancer Registry between 1995 and 2008. One-way ANOVA compared the differences between various groups. Multivariate logistic regression analysis was performed to determine the factors associated with the harvest of 12 or more lymph nodes for pathologic examination.
  
  
  RESULTS
  There were 19,240 patients with resectable colon cancer included in our analysis. Mean number of lymph nodes retrieved increased with later year of diagnosis, higher overall stage, higher T descriptor, age <65 years, poorer differentiation and right-sided tumors (P < 0.01 for all covariates). These aforementioned factors are also associated with an increased probability of retrieving 12 or more lymph nodes after surgical resection (P < 0.01 for all covariates).
  
  
  CONCLUSIONS
  Later year of diagnosis, younger patients, right-sided tumors, poorer differentiation, higher T descriptor and overall stage are associated with increased number of lymph nodes retrieved. These may indicate the presence of an immunological response of tumor versus host affecting lymph node retrieval.
authors.affiliation: Creighton University School of Medicine, Division of Hematology/Oncology, Omaha, Nebraska 68131, USA.
authors.forename: Wilson I
authors.initials: WI
authors.lastname: Gonsalves
authors.forename: Swapna
authors.initials: S
authors.lastname: Kanuri
authors.forename: Tsewang
authors.initials: T
authors.lastname: Tashi
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Aldoss
authors.forename: Ashwin
authors.initials: A
authors.lastname: Sama
authors.forename: Islam
authors.initials: I
authors.lastname: Al-Howaidi
authors.forename: Ashwin
authors.initials: A
authors.lastname: Ganta
authors.forename: Mudappa
authors.initials: M
authors.lastname: Kalaiah
authors.forename: Ramya
authors.initials: R
authors.lastname: Thota
authors.forename: Jairam
authors.initials: J
authors.lastname: Krishnamurthy
authors.forename: Xiang
authors.initials: X
authors.lastname: Fang
authors.forename: Peter
authors.initials: P
authors.lastname: Townley
authors.forename: Apar K
authors.initials: AK
authors.lastname: Ganti
authors.forename: Shanmuga
authors.initials: S
authors.lastname: Subbiah
authors.forename: Peter T
authors.initials: PT
authors.lastname: Silberstein
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery*; D008297:Male; D012042:Registries; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D014728:Veterans / Q000706:statistics & numerical data*