The reason for this may be two-fold: first, more recent results showed that SCLC patients did not receive a long-term overall survival benefit from individual PD-1/PD-L1 therapies, and FDA-approved indications for these drugs were withdrawn [15,16,17,18,19]; secondly, the presence of the founder EGFR mutation in subsequent biopsies of these patients suggests that these tumors retain NSCLC-mutant characteristics, which now poorly respond to immune checkpoint inhibitors [20,21,22]. This evidence concerns the gene EGFR and non-small cell lung carcinoma.