Difficulties in diagnosis and management of ectopic Cushing syndrome

A 18-year-old man presented to a local hospital with muscle weakness, facial edema, and a 6 kg weight gain over 2 months. After a complete work-up, he was diagnosed with pituitary Cushing syndrome and treated with a bilateral adrenalectomy for Cushing syndrome and pituitary radiotherapy for Nelson syndrome. Twenty-five years later, his ectopic source of adrenocorticotropic hormone was revealed as a pulmonary neuroendocrine tumor, and a pulmonary resection was performed. Subsequently, a biochemical and clinical remission including hyperpigmentation was achieved.