Objective  To investigate the prognostic factors and survival of patients with combined small cell lung cancer (C-SCLC) after they underwent complete resection.

  Methods  The clinical records of C-SCLC patients who were subjected to complete resection and systematic nodal dissection in one institution between January 2010 and December 2014 were retrospectively reviewed.

  Results  Seventy-eight patients with histologically diagnosed C-SCLC were identified. The most common combined component was large cell neuroendocrine carcinoma (LCNEC) (n=42), followed by squamous cell carcinoma (SCC) (n=18), adenocarcinoma (AC) (n=10), and adenosquamous carcinoma (ASC) (n=8). The overall survival (OS) rate of the entire cohort was 39.1%. Multivariate analyses using Cox's proportional hazard models revealed that size < 3 cm vs. >3 cm; hazard ratio (HR)=0.406; 95% confidence interval (CI)=0.202-0.816; P=0.011, performance status ( < 2 vs. >2; HR=0.113; 95% CI=0.202-0.631; P=0.013), combined non-small cell lung cancer (NSCLC) components (LCNEC vs. non-LCNEC, HR=3.00; 95% CI=0.096-0.483; P < 0.001), stage ⅢA vs. Ⅰ; HR=0.195, 95%CI: 0.063-0.602; P=0.004) and adjuvant therapy (yes vs. no, HR=0.402; 95% CI=0.195-0.831; P=0.014) were significant prognostic factors of OS.

  Conclusion  The mixed NSCLC components within C-SCLC significantly influence survival. Adjuvant therapy is beneficial for patients with complete resection of C-SCLC.