title: Pseudo-tumours of the thymus after correction of hypercortisolism in patients with ectopic ACTH syndrome: a report of five cases.
abstract: We report the cases of four patients with occult, and one patient with overt, ectopic ACTH syndrome. Cushing's syndrome was cured by removal of the ACTH secreting tumour, op'DDD, ketoconazole or bilateral adrenalectomy. Six to 14 months after remission of hypercortisolism, follow-up computed tomography or magnetic resonance imaging of the thorax revealed in all five patients an anterior mediastinal mass 3-5 cm in length that suggested a thymic carcinoma. Exploratory thoracotomy was performed in four cases and allowed the removal of an enlarged, but normal, thymus. Histological examination revealed no tumour but showed benign thymic hyperplasia with negative immunostaining for ACTH. Thymic enlargement spontaneously disappeared 11 months after its demonstration in the patient who did not undergo thoracotomy. The mechanism of this abnormality is thought to be thymic depletion resulting from high plasma cortisol concentrations followed by 'rebound' thymic hyperplasia when cortisol levels fall. Physicians involved in the management of patients with Cushing's syndrome must be aware of this entity in order to avert a diagnostic thoracotomy.
authors.affiliation: Centre Hospitalier Universitaire de Bordeaux, Department of Endocrinology A, Bordeaux-Pessac, France.
authors.forename: A
authors.initials: A
authors.lastname: Tabarin
authors.forename: B
authors.initials: B
authors.lastname: Catargi
authors.forename: P
authors.initials: P
authors.lastname: Chanson
authors.forename: S
authors.initials: S
authors.lastname: Hieronimus
authors.forename: J B
authors.initials: JB
authors.lastname: Corcuff
authors.forename: F
authors.initials: F
authors.lastname: Laurent
authors.forename: M
authors.initials: M
authors.lastname: Harter
authors.forename: J
authors.initials: J
authors.lastname: Drouillard
authors.forename: P
authors.initials: P
authors.lastname: Roger
mesh_terms: D000182:ACTH Syndrome, Ectopic / Q000097:blood / Q000188:drug therapy*; D000328:Adult; D003480:Cushing Syndrome / Q000628:therapy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013952:Thymus Hyperplasia / Q000175:diagnosis / Q000209:etiology*; D013953:Thymus Neoplasms / Q000175:diagnosis; D014057:Tomography, X-Ray Computed
chemical_list: D006854:Hydrocortisone