Combinational immunotherapy based on immune checkpoints inhibitors in small cell lung cancer: is this the beginning to reverse the refractory situation?

Small cell lung cancer (SCLC), a particular neuroendocrine tumor, occupies 13% of lung cancers, with the highest mortality among cancers. Immune checkpoints inhibitors (ICIs) based on programmed cell death protein-1 (PD-1)/programmed cell death one ligand (PD-L1) inhibitors and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors have been one of the most favorable therapies in SCLC. Simultaneously, not all the patients respond to...