EGFR and stomatitis: Solid evidence validated the application in NSCLC with EGFR mutant.[6,11,12] Prior to our study, there were few reports about dacomitinib with conventional dosage inducing hepatotoxity.[13] The common adverse effects included diarrhea, paronychia, dermatitis acneiform, stomatitis, and decreased appetite.[14] There were few reports of liver injury induced by dacomitinib.