EGFR and non-small cell lung carcinoma: EGFR-TKIs are widely used in NSCLC with EGFR mutations, but there have been no randomized clinical trials to evaluate their efficacy in the treatment of CSCLC, only small case series studies have suggested that EGFR-TKIs may be helpful in the treatment of CSCLC and SCLC, so the efficacy of EGFR-TKIs in the treatment of CSCLC or SCLC may not be as good as in NSCLC [27, 28].