ACTH and cortisol levels were strikingly high (60.8 pmol/L and 1575 nmol/L, respectively) on the admission day (day 1) (Table 2), which may be explained by physical stress and diabetic ketoacidosis; however, having learned from a previously reported a case of nivolumab-induced hypophysitis leading to secondary adrenal insufficiency after transient ACTH elevation [5], we frequently monitored the patient ACTH and cortisol levels. Here, POMC is linked to hypophysitis.