EGFR and cancer: Especially, specific molecular targeted agents have shown significant effect in certain patient subpopulations, such as the effect of EGFR inhibitors in EGFR-mutated non-small-cell lung cancers (NSCLC) (Solassol et al., 2019), BRAF inhibitors in advanced BRAF V600-mutated melanoma (Kim et al., 2014), and PARP inhibitors in cancer patients carrying BRCA mutations (Fong et al., 2009).