Abstract

A case of strumal carcinoid arising in the wall of a mucinous cystadenoma of the left ovary was studied by histological and histochemical techniques. Histologically the tumor was characterized by the presence of carcinoid element of trabecular type merged imperceptibly with thyroid follicle-like structure filled with colloidal materials. Both tumor cells of the carcinoid component and lining cell of the thyroid follicular structure showed intracytoplasmic granules with argentaffin as well as argyrophilic reactions. The stroma of the tumor failed to reveal amyloid on crystal violet and Congo red stains. Histogenesis of a strumal carcinoid was discussed in details with emphasis on monophyletic development of both carcinoid and follicular structures.