Clinical Features and Progression Pattern of Acquired T790M-positive Compared With T790M-negative EGFR Mutant Non–small-cell Lung Cancer: Catching Tumor and Clinical Heterogeneity Over Time Through Liquid Biopsy

Clinical features and disease course of patients with epidermal growth factor receptor (EGFR)-mutant non–small-cell lung cancer progressing to first-line EGFR-tyrosine kinase inhibitors might be heterogeneous. Age younger than 65, common EGFR mutations, overall response, and typical progression pattern might predict the T790M-positive status. Serial liquid biopsies during treatment could be useful in this population, especially when tissue rebiopsy is not feasible.