EGFR and non-small cell lung carcinoma: Despite the close association between EGFR mutations and EGFR-TKIs responsiveness, NSCLC patients, who had no detectable EGFR mutations, have been reported to benefit from the EGFR-TKIs [7]–[9] and erlotinib remains an important second-line treatment option in the clinical practice guidelines for NSCLC, irrespective of biological characteristics [10]–[12].