Although lung cancer is the leading cause of cancer-related death worldwide,[1] the recent discovery of driver oncogene alterations such as epidermal growth factor receptor mutations or anaplastic lymphoma kinase rearrangements and the identification of their targeted inhibitors have dramatically improved outcomes in a subset of highly selected lung cancer patients.[2–4] Consequently, the emergence of personalized therapies for non-small cell lung cancer underscores the need for cytologic or tissue verification of lung cancer. This evidence concerns the gene EGFR and lung cancer.