Real-world efficacy of PD-1/PD-L1 inhibitors in patients with advanced pulmonary neuroendocrine carcinoma: a single-center analysis

Abstract

Background: Immunotherapy blocking programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) has revolutionized the treatment of extensive-stage small-cell lung cancer (SCLC), but only with limited real-world efficacy data; evidence from immunotherapy for other pulmonary neuroendocrine carcinoma (PNEC) is scarce. Objective: The purpose of this study is to evaluate the efficacy of receiving PD-1/PD-L1 inhibitors in patients with advanced PNEC and explore factors related to survival prognosis, providing clues for treatment for patients with advanced PNEC. Methods: In all, 203 patients with advanced PNEC who received PD-1/PD-L1 inhibitors between January 2019 and December 2021 were retrospectively analyzed. Kaplan–Meier curves were constructed for progression-free survival (PFS) and overall survival (OS). Results: For the 203 patients, the objective response rate (ORR) was 48.3%, the disease control rate (DCR) was 83.3%, the median PFS (mPFS) was 6.0 months, and the median OS (mOS) was 13.1 months. Among them, the histology was 166 SCLC, 13 large-cell neuroendocrine carcinoma, and 24 other unspecified PNEC. Histologically, no significant difference was observed in PFS ( p = 0.240) or OS ( p = 0.845). In first-line (1L) treatment ( N = 125), patients received chemoimmunotherapy and had an ORR of 64.8%, DCR of 92.0%, mPFS of 6.6 months, and mOS of 14.9 months. In second-line (2L) or later-line setting, the ORR, DCR, mPFS, and mOS were 21.8%, 69.2%, 4.4, and 9.4 months; immunotherapy plus small-molecule antiangiogenic agents showed significantly greater PFS than immunotherapy monotherapy or chemoimmunotherapy (6.4 vs 1.4 vs 3.7 months, p = 0.041). Patients without liver metastasis had superior PFS (7.0 vs 5.1 months, p < 0.001) and OS (19.2 vs 9.6 months, p < 0.001) than those with liver metastasis. Conclusion: In clinical practice, PD-1/PD-L1 inhibitors are effective in patients with advanced PNEC, regardless of the pathological histology. The efficacy of 1L immunochemotherapy is worthy of recognition, and the addition of small-molecule antiangiogenic agents to immunotherapy in 2L or later-line treatment provides a better survival trend. Design: Retrospective study.