RESUMEN
INTRODUCTION: The optimal management of large cell neuroendocrine cancer of the lung (LCNEC) is unclear, and data regarding anti-programmed cell death protein 1 (PD-1) antibodies are scarce. This study reports the clinical efficacy of a PD-1 inhibitor in patients with advanced LCNEC. METHODS: All patients with stage III to IV LCNEC treated with at least one previous cycle of chemotherapy between January 1, 2015 and December 31, 2018 were reviewed retrospectively. Patients were divided into two groups depending on their exposure to nivolumab as second-line treatment or beyond. The primary objective was to assess nivolumab's efficacy. RESULTS: A total of 51 patients with advanced LCNEC from eight centers were analyzed, including 17 who received nivolumab. The PD-1 inhibitor was used as second-line treatment in 77% of cases, with a median number of eight doses (range: 1-62). After nivolumab treatment, the median overall survival was 12.1 months (95% confidence interval [CI]: 7.10-14.20). The objective response rate was 29.4% (95% CI: 10.3-56.0), and median progression-free survival was 3.9 months (95% CI: 1.68-7.17). The programmed death-ligand 1 status was unknown. There was no difference in the efficacy of first-line chemotherapy; the objective response rate was 23.5% (n = four of 17) in the nivolumab group versus 32.4% (n = 11 of 34) in the conventional treatment group, and progression-free survival was 3.5 months (95% CI: 1.7-4.4) versus 2.1 months (95% CI: 1.4-4.2), respectively. CONCLUSIONS: In a real-world setting, nivolumab seems to be an effective second-line treatment in patients with advanced LCNEC. Large prospective studies in this setting are still required.