title: Lymphatic invasion predicts survival in patients with early node-negative non-small cell lung cancer.
abstract: OBJECTIVE
  The aim of this study was to assess the influence of lymphatic and vascular invasion on overall survival in patients with surgically resected non-small cell lung cancer (NSCLC) without lymph node and distant metastases.
  
  
  METHODS
  From January 1999 to December 2009, a total of 190 NSCLC patients with node-negative pT1-pT4 disease underwent radical resection with lymphadenectomy. Pathologic reports were reclassified to the TNM-7 version, and the influence of lymphatic and vascular invasion on overall survival was examined using Kaplan-Meier and adjusted Cox proportional hazards analyses.
  
  
  RESULTS
  Lymphatic invasion was present in 34 (17.9%) and vascular invasion in 28 (14.7%) of 190 cases. Lymphatic and vascular invasions were correlated with higher Union for International Cancer Control stages (P = .056 and P = .011, respectively) and poor differentiated tumors (P = .051 and P = .012, respectively). There was no difference between pT1a and pT1b tumors in the presence of lymphatic (P = .912) or vascular (P = .134) invasion. Survival analyses revealed lymphatic (P < .001) and vascular (P = .008) invasion as statistically significant for the entire study population. Multivariable Cox analysis adjusted for age, Union for International Cancer Control stage, and lymphatic and vascular invasion confirmed lymphatic, but not vascular, invasion as an independent prognostic factor (P < .001; hazard ratio, 3.002; 95% confidence interval, 1.780-5.061). Especially in early stages, lymphatic invasion was associated with poorer overall survival in pT1a (P < .001), pT1b (P = .019), and pT2a (P = .028) tumors.
  
  
  CONCLUSIONS
  Lymphatic invasion represents an independent risk factor for node-negative NSCLC. Its implications on therapy decision making should be further evaluated, especially in early stages.
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Nentwich
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Bohn
authors.forename: Faik G
authors.initials: FG
authors.lastname: Uzunoglu
authors.forename: Matthias
authors.initials: M
authors.lastname: Reeh
authors.forename: Alexander
authors.initials: A
authors.lastname: Quaas
authors.forename: Tobias J
authors.initials: TJ
authors.lastname: Grob
authors.forename: Daniel
authors.initials: D
authors.lastname: Perez
authors.forename: Asad
authors.initials: A
authors.lastname: Kutup
authors.forename: Maximilian
authors.initials: M
authors.lastname: Bockhorn
authors.forename: Jakob R
authors.initials: JR
authors.lastname: Izbicki
authors.forename: Yogesh K
authors.initials: YK
authors.lastname: Vashist
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008197:Lymph Node Excision / Q000009:adverse effects / Q000401:mortality; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011013:Pneumonectomy / Q000009:adverse effects / Q000401:mortality; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: 10.2; 10.4; CT; NSCLC; TNM; UICC; Union for International Cancer Control; YSR; computed tomographic; non–small cell lung cancer; tumor, nodes, and metastasis; year survival rate