title: Density of tumor-infiltrating lymphocytes correlates with disease recurrence and survival in patients with large non-small-cell lung cancer tumors.
abstract: BACKGROUND
  The density of tumor-infiltrating lymphocytes (TIL) in lung cancer is variable and may have an impact on disease course. We reviewed the histology of lobectomy specimens from patients with pathologic stage IA-IB non-small-cell lung cancer to determine the impact of TILs on recurrence and survival.
  
  
  METHODS
  Two hundred nineteen lobectomies performed between 2002 and 2005 for stage IA-IB non-small-cell lung cancer were reviewed. Patients were stratified according to tumor size. Infiltrating patterns were graded as follows: group 1 (none to mild infiltrate) or group 2 (moderate to severe infiltrate). Recurrence rates and disease-free survival were compared between groups in each tumor size cohort.
  
  
  RESULTS
  A higher density of TILs was associated with lower disease recurrence (60%, group 1 versus 21%, group 2, P=0.02) and improved 5-y disease-free survival (35.9%, group 1 versus 75.6%, group 2, P=0.04) in patients with tumors 5 cm or greater in diameter. There were no correlations in patients with smaller tumors.
  
  
  CONCLUSIONS
  A higher degree of TILs within large node-negative non-small-cell lung cancer correlates with decreased risk of disease recurrence and improved disease-free survival. This subset of patients with tumor infiltration needs to be examined more closely with regards to outcomes of adjuvant chemotherapy.
authors.affiliation: Heart, Lung, and Esophageal Surgery Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Arman
authors.initials: A
authors.lastname: Kilic
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Landreneau
authors.forename: James D
authors.initials: JD
authors.lastname: Luketich
authors.forename: Arjun
authors.initials: A
authors.lastname: Pennathur
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Schuchert
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D002452:Cell Count; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D016246:Lymphocytes, Tumor-Infiltrating / Q000473:pathology*; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D009367:Neoplasm Staging; D011013:Pneumonectomy; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome