EGFR-L681Q

MCG

The L861Q mutation results in an amino acid substitution at position 861 in EGFR, from a leucine (L) to a glutamine (Q). This mutation occurs within exon 21, which encodes part of the kinase domain, and occurs with a frequency of approximately 2% in EGFR-mutated lung tumors (Mitsudomi and Yatabe 2010).

This mutation is associated with increased sensitivity to the EGFR TKIs, erlotinib (Tarceva) and gefitinib (Iressa; Lynch et al. 2004).