ABSTRACT
A 70-year-old woman who developed a moon face was hospitalized. At admission, adrenocorticotropic hormone (ACTH) and serum cortisol levels were elevated. A high-dose dexamethasone suppression test demonstrated that cortisol secretion was uninhibited. Furthermore, chest computed tomography revealed an anterior mediastinal mass. On the basis of these results, ectopic ACTH syndrome was diagnosed and complete resection of the thymic tumor was performed. Histological examination revealed large cell neuroendocrine carcinoma of the thymus and positive immunoreactivity for ACTH. However, despite complete excision of the thymic tumor, ACTH and serum cortisol levels were high. Therefore, we investigated whether the lesion had recurred or metastasized; however, the results were inconclusive. Finally, laparoscopic bilateral adrenalectomy was performed to control the hypercortisolemia. After the surgery, the serum cortisol level was well-controlled and the general condition of the patient was good.