title: Prognostic impact of vascular and lymphovascular invasion in early lung cancer.
abstract: BACKGROUND
  The prognostic significance of vascular and lymphatic invasion in non-small-cell lung cancer is under continuous debate. We analyzed the effect of tumor aggressiveness (lymphatic and/or vessel invasion) on survival and relapse in stage I and II non-small-cell lung cancer.
  
  
  METHODS
  We retrospectively analyzed prospectively collected data of 457 patients with stage I and II non-small-cell lung cancer from 1998 to 2008. Specimens were analyzed for intratumoral vascular invasion and lymphovascular space invasion. Overall survival and disease-free survival were estimated using the Kaplan-Meier method, and differences were determined by the logrank test. Cox regression analysis was performed to identify independent risk factors.
  
  
  RESULTS
  The incidence of intratumoral vascular invasion was 23.4%, and this correlated significantly with grade of differentiation, visceral pleural involvement, lymphovascular space invasion, and N status. The incidence of lymphovascular space invasion was 5.5%, and this correlated significantly with grade of differentiation, lymph nodes involved, and intratumoral vascular invasion. On multivariate analyses, intratumoral vascular invasion proved to be an significant independent risk factor for overall survival but not for disease-free survival. Lymphovascular space invasion was associated significantly with early tumor recurrence but not with overall survival.
  
  
  CONCLUSIONS
  Vascular and lymphatic invasion can serve as independent prognostic factors in completely resected non-small-cell lung cancer. Intratumoral vascular invasion and lymphovascular space invasion in early stage non-small-cell lung cancer are important factors in overall survival and early tumor recurrence. Further large scale studies with more recent patient cohorts and refined histological techniques are warranted.
authors.affiliation: Thoracic Oncology Research Group, St. James's Hospital, Dublin, Ireland.
authors.forename: Bassel S
authors.initials: BS
authors.lastname: Al-Alao
authors.forename: Kathy
authors.initials: K
authors.lastname: Gately
authors.forename: Siobhan
authors.initials: S
authors.lastname: Nicholson
authors.forename: Eilis
authors.initials: E
authors.lastname: McGovern
authors.forename: Vincent K
authors.initials: VK
authors.lastname: Young
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: O'Byrne
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001808:Blood Vessels / Q000473:pathology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D002454:Cell Differentiation; D016009:Chi-Square Distribution; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: Carcinoma; Lung neoplasms; Neoplasm invasiveness; Prognosis; Survival rate; non-small-cell lung