Abstract
BACKGROUND: Ataxia telangiectasia mutated (ATM) mutations represent the most common homologous recombination deficiency (HRD) mutation in non-small cell lung cancer (NSCLC). However, their therapeutic role in NSCLC has not been established. CASE: Here, we present a case of a 91-year-old male with metastatic NSCLC who progressed on multiple lines of treatment. Next-generation sequencing revealed ATM mutations, leading to the initiation of olaparib, which successfully achieved remission over a two-year period. CONCLUSION: This case underscores the promising role of olaparib in treating NSCLC with HRD, particularly ATM mutations, highlighting the importance of molecular testing and targeted therapies.