Progress of Immune Checkpoint Inhibitors 
in the Treatment of Advanced Pulmonary Neuroendocrine Tumors

Abstract

Pulmonary neuroendocrine tumors (PNETs) are a kind of epithelial tumors originating from pulmonary neuroendocrine cells, accounting for about 20% of primary lung tumors, including typical carcinoid, atypical carcinoid, small cell carcinoma, and large cell neuroendocrine carcinoma. The morphologic and clinical characteristics of these four types of PNETs are relatively highly heterogeneous. Immune checkpoint inhibitors (ICIs) have been shown robust antitumor activity in a variety of solid tumors. Treatment regimens of advanced PNETs have developed greatly in the past decade, but ICIs are still in their infancy in the field of PNETs. This review focuses on the landscape of current clinical trials and research as well as the situation of ICIs-related biomarkers in PNETs.

Keywords

• pulmonary neuroendocrine tumors
• immune checkpoint inhibitors
• biomarkers
• immnotherapy