Neurohormonal peptides and argyrophil cells in an androblastoma of the ovary. An ovarian epithelial tumour is described with a compound histological structure containing features of an androblastoma with well differentiated Sertoli-Leydig cell structures and features resembling a carcinoid tumour. Scattered argyrophil cells were demonstrated in both components of the tumour. Neurohormonal peptides were found immunocytochemically in a minor fraction of the argyrophil cells. These included pancreatic polypeptide (PP), glucagon/enteroglucagon and enkephalin. These findings indicate a high degree of multipotentiality of the progenitor cells of the neoplasm.