EGFR and lung adenocarcinoma: Frequent overexpression and activation of EGFR has also been reported in histologically normal and hyperplastic bronchial epithelium from smokers [13], bronchial preneoplasia [14], and in histologically normal bronchial epithelium adjacent to lung adenocarcinomas [15], indicating the possibility that alterations in EGFR signaling represent an early event and may represent a target for chemopreventive agents.