Clinical Outcomes of Postoperative Adjuvant Chemotherapy for Surgically Resected High-Grade Pulmonary Neuroendocrine Carcinoma

Abstract

Introduction: Data on the clinical outcomes of patients receiving adjuvant chemotherapy for surgically resected high-grade pulmonary neuroendocrine carcinoma (HGNEC) (large-cell neuroendocrine carcinoma and small-cell lung cancer) are limited. This study aimed to evaluate the prognostic significance of adjuvant chemotherapy in patients with HGNEC. Methods: We retrospectively analyzed patients with surgically resected HGNEC at five institutions in Japan between January 2006 and May 2016. Results: A total of 143 patients were enrolled. Among them, 65 received adjuvant chemotherapy. Four patients who participated in clinical trials were excluded; the remaining 61 patients were included in the study. Fifty-six patients received adjuvant small-cell lung cancer-based chemotherapy. Twenty-five of 29 patients who relapsed after postoperative adjuvant chemotherapy received chemotherapy. The most commonly administered chemotherapy agent was amrubicin. The 3-year relapse-free and overall survival rates were 55.2% and 66.8%, respectively. The median relapse-free and overall survival times for the 25 patients who received chemotherapy after relapse were 12.9 and 27.5 months, respectively. Among them, 22 relapsed within 2 years. Patients who received platinum-doublet chemotherapy after relapse tended to have better time to progression disease and overall survival than those who received single-agent chemotherapy. Conclusions: Most patients with HGNEC received small-cell lung cancer-based regimens as postoperative adjuvant chemotherapy. Those who relapsed after adjuvant chemotherapy were mainly treated with amrubicin. Our findings suggest that platinum-doublet chemotherapy tends to improve the time to progression disease and overall survival in patients who relapse after postoperative adjuvant chemotherapy.