title: Long-term outcomes after lobectomy for non-small cell lung cancer when unsuspected pN2 disease is found: A National Cancer Data Base analysis.
abstract: OBJECTIVE
  There are few studies evaluating whether to proceed with planned resection when a patient with non-small cell lung cancer (NSCLC) unexpectedly is found to have N2 disease at the time of thoracoscopy or thoracotomy. To help guide management of this clinical scenario, we evaluated outcomes for patients who were upstaged to pN2 after lobectomy without induction therapy using the National Cancer Data Base (NCDB).
  
  
  METHODS
  Survival of NSCLC patients treated with lobectomy for clinically unsuspected mediastinal nodal disease (cT1-cT3 cN0-cN1, pN2 disease) from 1998-2006 in the NCDB was compared with "suspected" N2 disease patients (cT1-cT3 cN2) who were treated with chemotherapy with or without radiation followed by lobectomy, using matched analysis based on propensity scores.
  
  
  RESULTS
  Unsuspected pN2 disease was found in 4.4% of patients (2047 out of 46,691) who underwent lobectomy as primary therapy for cT1-cT3 cN0-cN1 NSCLC. The 5-year survival was 42%, 36%, 21%, and 28% for patients who underwent adjuvant chemotherapy (n = 385), chemoradiation (n = 504), radiation (n = 300), and no adjuvant therapy (n = 858), respectively. Five-year survival of the entire unsuspected pN2 cohort was worse than survival of 2302 patients who were treated with lobectomy after induction therapy for clinical N2 disease (30% vs 40%; P < .001), although no significant difference in 5-year survival was found in a matched-analysis of 655 patients from each group (37% vs 37%; P = .95).
  
  
  CONCLUSIONS
  This population-based analysis suggests that, in the setting of unsuspected pN2 NSCLC, proceeding with lobectomy does not appear to compromise outcomes if adjuvant chemotherapy with or without radiation therapy can be administered following surgery.
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC.
authors.forename: Chi-Fu Jeffrey
authors.initials: CF
authors.lastname: Yang
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC.
authors.forename: Arvind
authors.initials: A
authors.lastname: Kumar
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Gulack
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Mulvihill
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC.
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Hartwig
authors.affiliation: Department of Biostatistics, Duke University, Durham, NC.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, NC.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: D'Amico
authors.affiliation: Department of Cardiothoracic Surgery, Stanford University Medical Center, Stanford, Calif. Electronic address: berry037@stanford.edu.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Berry
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D002423:Cause of Death; D017024:Chemotherapy, Adjuvant; D015331:Cohort Studies; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000188:drug therapy / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008482:Mediastinum; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D019990:Perioperative Care / Q000379:methods; D011013:Pneumonectomy / Q000379:methods; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
keywords: lung cancer surgery; unsuspected N2