Panhypopituitarism Induced by CTLA-4 and PD-1/PD-L1 Inhibitor Immunotherapy

A 63-year-old male patient treated with ipilimumab and nivolumab for renal cell carcinoma developed hypophysitis, an immune-related adverse effect of immunotherapy, presenting with symptoms such as general weakness, malaise, disorientation, and severe hyponatremia. Laboratory tests revealed central hypothyroidism, secondary adrenal insufficiency, and transient hypogonadotropic hypogonadism, which later resolved. The patient was treated with 3% NaCl and glucocorticoids, and discharged on oral hydrocortisone and levothyroxine. The case underscores the importance of clinicians being aware of and monitoring for immunotherapy-induced endocrinopathies, which can manifest with fatigue, headache, and hormonal deficiencies. While some pituitary function may recover, adrenal insufficiency often persists and can be life-threatening, necessitating prompt recognition and treatment.