Retrospective Analysis of Nivolumab-Induced Isolated Adrenocorticotropin Deficiency.

To investigate the clinical features of nivolumab-induced isolated adrenocorticotropin deficiency and to provide a reference for the diagnosis, treatment and rational use of nivolumab, clinical reports of nivolumab induced isolated adrenocorticotropin deficiency were collected by searching the database until August 31, 2025. Clinical data were collected and retrospectively analyzed. Seventy-one patients were enrolled, with a median age of 66 years (range: 26-87), and 73.2% of whom were male and 67.6% from Japan. Melanoma (36.6%) was the main indication for nivolumab. The median time from initiation of nivolumab to the onset of isolated adrenocorticotropin deficiency was 24 weeks (range: 3-60) and the median was 8 cycles (range: 2-33). Fatigue (76.1%), anorexia (66.2%) and nausea (23.9%) were the most common symptoms of isolated adrenocorticotropin deficiency. Laboratory tests revealed hyponatremia (50.7%) and eosinophilia (28.2%). Pituitary magnetic resonance imaging showed no abnormality in most patients (71.8%). Thyroid dysfunction (26.8%) often coexists with isolated adrenocorticotropin deficiency. These patients had a good prognosis after receiving a physiological dose of hydrocortisone. Nivolumab-induced isolated adrenocorticotropin deficiency is a rare disorder with possible racial differences. The possibility of isolated adrenocorticotropin deficiency should be considered in patients with fatigue and fatigue during treatment. Serum sodium and eosinophil ratios should also be closely monitored. The prognosis is good after hydrocortisone replacement therapy.