InterpretationSomatic mutations in BRAF have been found in up to 10% of all NSCLC, more common in adenocarcinomas. D594 is a highly conserved residue within the kinase domain of BRAF and mutation of this residue appears to result in kinase inactivation. In vitro study has shown that kinase-dead BRAF forms a constitutive complex with CRAF in the presence of activated RAS leading to MEK and ERK signaling.While clinical trials targeting BRAF-mutant NSCLC have mostly focused on patients with V600E-mutant disease, in vitro studies suggests potential sensitivity to targeted agents in cell lines with inactivating BRAF non-V600 mutations. However, established clinical activity of targeted BRAF and MEK inhibition in patients with these mutations has yet to be fully elucidated and further study is warranted. Clinical correlation is recommended.