title: A rare cause of Cushing's syndrome: an ACTH-secreting phaeochromocytoma.
abstract: Excess glucocorticoid levels cause Cushing's syndrome (CS) and may be due to pituitary, adrenal or ectopic tumours. Adrenocorticotropic hormone (ACTH) levels are useful in identifying adrenal tumours. In rare cases, ACTH-producing phaeochromocytomas are the cause of CS. We present two cases of ACTH-secreting phaeochromocytoma as the underlying cause of CS. In both cases, female patients presented with the classical clinical signs of CS and an adrenal mass. High ACTH levels raised the suspicion of an ACTH-secreting phaeochromocytoma. The diagnosis was confirmed by urinary catecholamine levels and positive fluorine-18-L-dihydroxyphenylalanine (18F-DOPA) positron emission tomography (PET) CT (Case 1) and fluorodeoxyglucose PET-CT (Case 2). Both patients were treated with an α-blocker prior to surgical intervention. The two cases underline the importance of thorough diagnostic workup in patients with CS. An ACTH-secreting phaeochromocytoma should be checked for in patients with an adrenal mass and elevated ACTH levels.
authors.affiliation: Odense University Hospital, Odense, Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Folkestad
authors.affiliation: Odense University Hospital, Odense, Denmark.
authors.forename: Marianne Skovsager
authors.initials: MS
authors.lastname: Andersen
authors.affiliation: Department of Nuclear Medicine, Odense University Hospital, Odense C, Denmark.
authors.forename: Anne Lerberg
authors.initials: AL
authors.lastname: Nielsen
authors.affiliation: Department of Endocrinology, Odense University Hospital, Odense C, Denmark.
authors.forename: Dorte
authors.initials: D
authors.lastname: Glintborg
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000378:metabolism; D000311:Adrenal Glands / Q000000981:diagnostic imaging; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D010673:Pheochromocytoma / Q000150:complications* / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000378:metabolism; D047748:Pituitary ACTH Hypersecretion / Q000209:etiology*; D011877:Radionuclide Imaging
chemical_list: D000324:Adrenocorticotropic Hormone