Immunotherapy Benefit in a Patient With Non-Small Cell Lung Cancer and a Rare BRAF Mutation.

Immunotherapy is less effective in non-small cell lung cancer (NSCLC) with driver mutations in epidermal growth factor receptor or anaplastic lymphoma kinase and some may extrapolate this trend to other driver mutations. Up to 4% of NSCLC cases contain a mutation. Most mutations are V600E, and little is known about the impact of treatment in rare G469A mutations. We present a case of a patient found to have G469A mutated NSCLC. She was diagnosed with Stage IIIB NSCLC and treated with concurrent chemotherapy and radiation. Post-treatment imaging demonstrated disease progression and she was started on nivolumab, resulting in a dramatic and prolonged response which is ongoing after 76 cycles. Her substantial response and prolonged benefit suggest that -mutated NSCLC may respond better than - or -driven disease to immunotherapy. Due to the rarity of specific mutations, this case adds to the limited current published literature on NSCLC harbouring a G469A mutation and suggests that immunotherapy is a reasonable treatment option.