Trends in management of locally advanced large cell neuroendocrine carcinoma of the lung.

Abstract

e21073 Background: Large cell neuroendocrine carcinoma (LCNEC) is a rare pulmonary malignancy with clinicopathologic features of both non-small cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). The optimal treatment approach for LCNEC is not well established, likely a result of the histology’s underrepresentation in randomized clinical trials. Given the paucity of available data regarding LCNEC management, we queried the National Cancer Database (NCDB) to describe trends in management, identify predictors of treatment receipt, and compare outcomes in patients receiving chemotherapy (ChT) and chemoradiotherapy (CRT). Methods: We identified patients with locally advanced (Stage III) LCNEC of the lung treated with definitive ChT or CRT between the years of 2004-2015. Odds ratios were calculated to determine predictors of CRT receipt. Multivariable cox regression was used to determine predictors of overall survival. Results: Using the above criteria, 6,802 patients were identified, 46% of whom received CRT (n = 3,153) while 39% (n = 2,644) received ChT alone. Median age of the entire cohort was 68 years old. Most patients had T4 (35%) and N2 (59%) disease. Median overall survival was 11.9 months (11.3-12.6) in patients receiving ChT compared to 16.1 months (15.4-16.9) in patients receiving CRT (p < 0.0001). Overall survival at 1, 3, and 5 years was 50%, 20%, and 13% versus 60%, 27%, and 18%, in patients receiving ChT and CRT, respectively. Older patients and those with higher comorbidity scores were less likely to receive CRT; whereas patients with higher education level, treatment receipt at an academic/research program facility, N2 disease, and later treatment year were more likely to receive CRT. On multivariable analysis, older age, greater comorbidity score, presence of N2 disease, and presence of T4 disease were all associated with decreased OS, whereby female sex, private insurance, higher income, lower T stage, and more recent treatment were associated with increased overall survival. CRT receipt was an independent predictor of increased overall survival. Conclusions: Definitive CRT was an independent predictor of increased overall survival in patients with locally advanced LCNEC of the lung. Findings from our study may help guide potential areas of future investigation to help define an ideal treatment approach for LCNEC.