Efficacy and Safety of Initial Low‐Dose, Extended‐Interval Nivolumab Monotherapy in a 91‐Year‐Old Patient With Locally Advanced NSCLC and Poor Performance Status: A Case Report

The incidence of non‐small cell lung cancer (NSCLC) increases with age, with approximately half of the cases diagnosed in individuals aged 70 and older. In numerous clinical trials, immune checkpoint inhibitors (ICIs) have demonstrated significant efficacy in treating NSCLC without driver gene mutations. However, elderly lung cancer patients, particularly those aged 80 and above, are underrepresented in clinical trials, resulting in limited information on the efficacy and safety of ICIs in this population. This report details the clinical course of a 91‐year‐old patient with locally advanced NSCLC and an Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 2. The patient received nivolumab monotherapy at a dose of 200 mg every 3 weeks for the first four cycles, and then the dose was adjusted to 240 mg every 3 weeks from the fifth cycle, with a total of 32 treatment cycles administered. Treatment was well‐tolerated without significant immune‐related adverse events (irAEs). A durable partial response (PR) was achieved, with progression‐free survival (PFS) exceeding 31 months. The patient maintained a favorable quality of life throughout the treatment period. This case suggests that initial low‐dose, extended‐interval individualized nivolumab therapy may serve as a treatment option for the oldest old patients with advanced NSCLC and poor PS.