EGFR and breast cancer: LMR has also been suggested as a prognostic factor in advanced-stage lung cancer patients receiving platinum-based chemotherapies[20], and in patients with breast cancer following neo-adjuvant chemotherapies.[17] To the best of our knowledge, this is the first study demonstrating that LMR is a prognostic factor in patients with advanced-stage, EGFR-mutant NSCLC receiving EGFR-TKIs.