EGFR T790M resistance mutation in non small-cell lung carcinoma

Lung cancer patients carrying sensitive epidermal growth factor receptor (EGFR) mutations show dramatic responses to tyrosine kinase inhibitors (TKIs). However, the majority of patients whose disease responds to drugs eventually develop resistance to these EGFR-TKIs. The T790M gatekeeper mutation in the EGFR tyrosine kinase domain accounts for half of resistance to these drugs. In some patients, this mutation is also detected as a primary event before drug exposure, at a frequency that is highly dependent on the technique used. This review will focus on the methods that have been used to detect the T790M mutation, and its potential clinical applications both in TKI naïve patients and in patients with an acquired resistance. •The EGFR T790M mutation can be detected in some treatment naïve NSCLC.•The reported frequencies are highly dependent on the techniques used.•Patients presenting the T790M mutation respond to tyrosine kinase inhibitors.•The T790M mutation accounts for half of resistance to tyrosine kinase inhibitors.•New inhibitors seem to be efficient in patients who acquired the T790M mutation.