title: Clinical outcomes of surgery after induction treatment in patients with pathologically proven N2-positive stage III non-small cell lung cancer.
abstract: BACKGROUND
  To assess the effect of preoperative neoadjuvant therapy on resectability, downstaging, and the prognosis in patients with stage IIIA-N2 non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Eighty-four patients who underwent resections after induction therapy [76 with neoadjuvant chemotherapy (CTx) and 8 with induction chemoradiotherapy (CRTx)] for clinically evident [larger than 1 cm on computed tomography (CT)] and pathologically confirmed ipsilateral N2 positive NSCLC (stage IIIA) between January 2009 and July 2013 were reviewed retrospectively.
  
  
  RESULTS
  Partial response (PR) was observed in 39 patients (46.4%). Standard lobectomy was performed in 63 cases (75.0%), and extensive resection was conducted in 21 cases (25.0%), including four pneumonectomies. Pathologic nodal downstaging (pN2 to pN0-1) was confirmed in 38 cases (45.2%). After induction therapy plus resection, 5-year progression-free survival (PFS) and overall survival (OS) in cases with radical resections were 37.9% and 34.2%, respectively. Patients who underwent lobectomy or pathologic nodal downstaging had better prognosis than those who had extensive resection or persistent N2 in PFS (P=0.036; P=0.025) and OS (P=0.023; P=0.024). On univariate analysis, lobectomy and pathological nodal downstaging were favourably predictive factors both in PFS and OS. Cox multivariate analyses identified only pathologic nodal downstaging to predict better PFS, and lobectomy to be significantly prognostic for OS.
  
  
  CONCLUSIONS
  These data suggest that neoadjuvant therapy was feasible, and helpful for tumor and pathologic nodal downstaging with promising rates of survival in patients with stage IIIA-N2 NSCLC. After induction therapy, patients with potentially radical lobectomy were more likely to benefit from operation. Pathological nodal downstaging of pN2 to pN0-1, rather than clinical response was predictive of a favorable outcome, and was correlated with a better chance of survival.
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai 200030, China.
authors.forename: Haitang
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai 200030, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Yao
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai 200030, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai 200030, China.
authors.forename: Heng
authors.initials: H
authors.lastname: Zhao
keywords: Non-small cell lung cancer (NSCLC); downstaging; neoadjuvant; surgery; survival