CSF Analysis in EGFR Mutant Non-Small Cell Lung Cancer With Leptomeningeal Disease

Leptomeningeal disease is malignant seeding of the leptomeninges and presents with a variety of symptoms frequently impacting quality of life. With improvement in treatment options, rates of leptomeningeal disease are increasing and currently found in up to 9% of EGFR mutant NSCLC. Systemic therapy may be more effective if it can target the correct molecular aberration. The molecular characterization of central nervous system disease may differ from disease outside of the central nervous system. The aim of this pilot trial is to evaluate for molecular differences between cerebral spinal fluid (CSF) and blood circulating tumor DNA (ctDNA) through the use of ddPCR and BC Cancer NGS panel molecular testing.