Gastric bypass surgery for treatment of hypothalamic obesity after craniopharyngioma therapy

Background: A 14-year-old boy presented with daytime somnolence, intermittent emesis and hypothyroidism. Neuroimaging revealed a calcified suprasellar intracranial mass, suspected to be a craniopharyngioma. Subtotal resection of the tumor confirmed the diagnosis. Extreme obesity (BMI >60 kg/m²) and hyperinsulinemia followed tumor resection and cranial irradiation. Dietary interventions were unsuccessful, and pharmacologic intervention (i.e. octreotide) only slowed the rate of weight gain.Investigations: Radiography documented the suprasellar mass. Following surgical resection and radiotherapy, hypothalamic-pituitary deficiencies were found. Preprandial and postprandial excursions of insulin, active ghrelin and leptin were measured before and after gastric bypass surgery.Diagnosis: Panhypopituitarism, hypothalamic obesity and hyperinsulinemia following craniopharyngioma therapy.Management: Severe caloric restriction, octreotide, and pituitary hormone replacement did not produce weight loss. Gastric bypass surgery led to reduced food cravings, significant weight loss, and amelioration of obesity-related comorbidities. Correction of fasting hyperinsulinemia, normalization of postprandial insulin responses, and reductions in active ghrelin and leptin concentrations were also observed.