In large clinical trials, like Checkmate 214, high-grade hypophysitis and all-cause adrenal insufficiency were rare [5], yet cohort studies highlight a higher prevalence of ICI-related pituitary dysfunctions (13.7-19% with anti-CTLA-4/anti-PD-1 combination therapy; 1-6% in monotherapies) [6, 7]. The gene discussed is CTLA4; the disease is Adrenal insufficiency.