A misleading cause of pseudo-thymic tumor in ectopic Cushing's syndrome.

A 27-year-old man was referred with typical features of severe Cushing's syndrome. A bilateral adrenalectomy was performed. Three months later, a triangular nodular mediastinal enlargement, evocative of a right anterior thymic tumor, was discovered. Thymectomy was undertaken. Histological examination revealed diffuse thymic hyperplasia with negative immunostaining for adrenocorticotropic hormone. Five years later, a right endobronchial tumor corresponding to a carcinoid tumor was removed.