Subsequent to the first report of IGF-1R activation in 2010 [21], AXL [37], Notch3 [50], and fibroblast growth factor receptor 3 (FGFR3) [38] are identified as receptor tyrosine kinases (RTKs) that cause drug tolerance in lung cancers with EGFR mutations. The gene discussed is AXL; the disease is lung carcinoma.