Thymic carcinoid tumor with Cushing's syndrome. Report of a case with electron microscopic and immunoperoxidase studies for neuron-specific enolase and corticotropin.

Abstract

A partially encapsulated, 11-cm-diameter anterior mediastinal mass was resected from a 26-year-old man who appeared with signs and symptoms of Cushing's syndrome. Electron microscopic study disclosed cytoplasmic neurosecretory granules and positive immunoperoxidase reactions for neuron-specific enolase and corticotropin in the tumor cells. A lymph node metastasis was detected 11/2 years after the operation. It appears that a thymic carcinoid tumor is a specific entity.