EGFR and lung adenocarcinoma: Postoperative specimen pathological examination verified the disease as lung adenocarcinoma, with immunohistochemical results (CK5/6(−), P40(−), TIF-1( +), Napsin-A( +), P53( +), Ki-67(+ , 3%), EGFR( +)), all resected lymph nodes were negative(Fig. 2).