Pituitary insufficiency, inappropriate antidiuretic hormone (ADH) secretion, and carcinoma of the bronchus

Abstract

A 50-year-old man presented with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and clinical and biochemical hypopituitarism. The clinical assessment was confirmed at autopsy where a bronchogenic oatcell carcinoma was found to have metastasized to the pituitary gland and hypothalamus. In addition, electron microscopy of the tumor revealed neurosecretory-type granules, and assay of the tumor showed it to be the source of ADH, which was probably arginine vasopressin. This appears to be a rare case showing: 1. clinical hypopituitarism due to secondary malignant deposits in the pituitary itself; 2. the combination of a bronchial carcinoma producing both SIADH and hypopituitarism and only the second reported case demonstrating 3. secretory granules of endocrine type on electron microscopy in an ADH-secreting bronchial carcinoma.