Clinical characteristics of adrenal insufficiency as an immune-related adverse event in non-small-cell lung cancer

Adrenal insufficiency (AI) is an immune-related adverse event of immune checkpoint inhibitors and on occasion could be serious. There have been few reports of clinical information regarding AI associated with anti-programmed cell death protein-1 (anti-PD-1) antibody in non-small-cell lung cancer (NSCLC) patients. Patients with advanced NSCLC treated with anti-PD-1 antibodies between December 2015 and October 2017 were identified from the medical records of our institution. We investigated the frequency, symptoms, test results, and treatment outcomes of AI, and prognosis of patients who developed AI. In total, 282 NSCLC patients were treated with anti-PD-1 antibodies, and 4 patients (1.4%) were diagnosed as AI and 6 patients (2.1%) as suspicious of AI according to the laboratory data or clinical findings. The median follow-up period was 13.6 months. All patients with AI and suspicious of AI were treated with corticosteroid replacement, and performance status (PS) was improved in 50% of patients. Two of 10 patients were thought to have central AI. Six patients of 10 patients continued to receive anti-PD-1 antibodies with corticosteroid hormone replacement after diagnosis. The median progression-free survival and overall survival were 10.2 and 15.4 months, respectively. In conclusion, the incidence of AI among NSCLC patients treated with anti-PD-1 antibodies was similar to previous studies. Corticosteroid replacement improved PS, symptoms, and laboratory data of patients with AI and suspicious of AI. Corticosteroid replacement may contribute to continuation of anti-PD-1 antibodies and survival outcome was preferable in patients with AI and suspicious of AI receiving corticosteroid treatment.