A patient-level synthesis of 40 published cases mapped nivolumab-induced hypophysitis, reporting predominant damage to the pituitary’s cortisol-regulating axis and strong responsiveness to corticosteroids. The analysis also found that recurrence with nivolumab re-challenge is rare. For oncology safety teams, a clearer side-effect profile helps refine monitoring protocols around endocrinopathies and supports risk-managed continuation strategies. Understanding which pituitary sub-axes are most affected also informs the choice and timing of hormone testing. The dataset represents a consolidated real-world experience base that can help clinical guideline committees and investigators design prospective monitoring studies.