A leopard can't change its spots: can a T790M mutation-positive cancer change its spots after epidermal growth factor receptor-tyrosine kinase inhibitor therapy?

Drug therapies for non-small cell lung cancer (NSCLC) have greatly progressed in recent years. Especially, the identification of epidermal growth factor receptor ( EGFR ) mutation has transformed the management of patients with EGFR-mutant NSCLC, who are sensitive to EGFR tyrosine kinase inhibitor (EGFR-TKI).