The T790M mutation is a specific alteration in the EGFR (Epidermal Growth Factor Receptor) gene, often associated with resistance to certain cancer therapies. This mutation involves a substitution of methionine for threonine at position 790. It is most commonly observed in patients with non-small cell lung cancer (NSCLC) who have initially responded to EGFR tyrosine kinase inhibitors (TKIs) but later developed resistance.
