title: Prognostic significance of visceral pleural involvement in early-stage lung cancer.
abstract: BACKGROUND
  Visceral pleural invasion (VPI) may impact non-small cell lung cancer (NSCLC) survival. However, previous studies are mixed as to whether VPI is an independent prognostic factor in early-stage cancers and whether its effect is size dependent. In the current American Joint Committee on Cancer (AJCC) staging system, VPI leads to upstaging of cancers < 3 cm but not of those 3 to 7 cm in size.
  
  
  METHODS
  Using the Surveillance, Epidemiology, and End Results (SEER) registry, we identified 16,315 patients with stage I-II NSCLC treated with lobectomy. We used the Kaplan-Meier method and Cox regression to assess the association of VPI with lung cancer-specific (primary outcome) and overall survival. Based on these results, we created a revised VPI staging classification.
  
  
  RESULTS
  Overall, 3,389 patients (21%) had VPI. Kaplan-Meier analysis stratified by tumor size showed worse cancer-specific survival in patients with VPI (P < .0001). VPI was independently associated with decreased lung cancer-specific survival (hazard ratio, 1.38; 95% CI, 1.29-1.47) after controlling for tumor size and other confounders; this effect was not size dependent. In our revised classification, tumors < 7 cm with VPI were upstaged to the next T category.
  
  
  CONCLUSIONS
  VPI is a prevalent finding associated with worse prognosis in early-stage lung cancer, even among patients with tumors > 3 cm, a factor not captured in the current staging system. Patients with VPI may be considered candidates for more aggressive treatment.
authors.affiliation: Division of General Internal Medicine, Icahn School of Medicine at Mount Sinai, New York, NY. Electronic address: slakha@post.harvard.edu.
authors.forename: Sameer
authors.initials: S
authors.lastname: Lakha
authors.affiliation: Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Gomez
authors.affiliation: Department of Thoracic Surgery, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Raja M
authors.initials: RM
authors.lastname: Flores
authors.affiliation: Division of General Internal Medicine, Icahn School of Medicine at Mount Sinai, New York, NY; Division of Pulmonary, Critical Care, and Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Juan P
authors.initials: JP
authors.lastname: Wisnivesky
mesh_terms: D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000556:secondary* / Q000628:therapy; D016001:Confidence Intervals; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D010994:Pleura / Q000473:pathology; D010997:Pleural Neoplasms / Q000401:mortality* / Q000556:secondary* / Q000628:therapy; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D018426:SEER Program; D016019:Survival Analysis