Late-onset hypothalamic-pituitary dysfunction in a childhood cancer survivor treated with cranial irradiation.

Hypothalamic-pituitary dysfunction is a well-recognized late complication in childhood cancer survivors (CCSs) treated with cranial irradiation. We report a 42-year-old male with a history of acute lymphoblastic leukemia diagnosed at 5 years of age and treated with chemotherapy and 26 Gray whole-brain irradiation. He presented with right upper extremity paresis due to bilateral chronic subdural hematomas. Following burr-hole drainage for the left chronic subdural hematoma, he developed anorexia, fatigue, and hyponatremia and was referred to the endocrinology department. Endocrine evaluation demonstrated hypothalamic adrenal insufficiency, severe adult growth hormone deficiency, mild gonadal dysfunction, and mixed hypothyroidism. Magnetic resonance imaging revealed a suprasellar arachnoid cyst with compression of the pituitary gland. To our knowledge, this represents one of the longest reported intervals between childhood cancer treatment and the diagnosis of hypothalamic-pituitary dysfunction, which became clinically apparent 37 years after treatment following a prolonged asymptomatic period. This case suggests that hypothalamic-pituitary dysfunction may remain clinically silent and gradually progress for decades before becoming unmasked by the physiological stress, highlighting the need for prolonged, potentially lifelong, endocrine surveillance in CCS.