Clinical characteristics and immunotherapy efficacy in advanced lung cancer patients with immune checkpoint inhibitor-related adrenal insufficiency

To investigate the clinical characteristics and treatment efficacy in advanced lung cancer patients with adrenal insufficiency (AI) induced by immune checkpoint inhibitors (ICIs). A retrospective study was conducted on advanced lung cancer patients who developed AI following ICI treatment at Lishui Central Hospital between January 2019 and November 2024. Patients from both the Oncology and Respiratory & Critical Care Departments were included. Clinical data, laboratory results, imaging findings, and the association between secondary AI onset and treatment efficacy were analyzed. A total of 35 patients were included in the study. Of these, 2 patients (5.7%) achieved complete response, 8 patients (22.9%) achieved partial response, 24 patients (68.6%) had stable disease and 1 case (2.9%) showed progressive disease. The overall response rate was 31.8%, with a duration of response of 100%. The median progression-free survival (PFS) for all patients was 10.9 months (95% CI: 6.959-14.841). PFS significantly differed between patients who developed secondary AI within 3 months of ICI initiation and those who developed it later (8.0 months vs 11.0 months, P = .033). Secondary AI is a rare but significant immune-related adverse event associated with ICIs. Advanced lung cancer patients with secondary AI tend to exhibit a more favorable response to immunotherapy. The timing of AI onset appears to critically influence ICI efficacy, with late-onset AI (>3 months) correlating with markedly prolonged PFS - a novel prognostic association not previously reported.