EGFR and cancer: Ishikawa and colleagues examined AREG concentrations in the blood serum of non-small cell lung cancer patients treated with Gefitinib—an orally administered inhibitor of EGFR tyrosine kinase—and like in our study, they demonstrated a dependency between higher AREG concentrations and shorter patient overall survival, which is probably related with the EGFR signaling pathway involved in the proliferation, invasion, and survival of cancer cells [43].