The radiological investigation of occult ectopic ACTH-dependent Cushing's syndrome.
The radiological features of 14 patients with Cushing's syndrome due to 'occult' ectopic ACTH syndrome have been reviewed. In 11 of the 14 patients (79%), the ACTH-producing tumour was located in the thorax. Bronchial carcinoid tumours (eight patients) were the single most common source of 'occult' ectopic ACTH production with thymic carcinoid tumours (two patients) and mediastinal metastases from a medullary carcinoma of the thyroid gland (one patient) accounting for the other intrathoracic tumours. The tumours were usually small with five of the eight bronchial carcinoid tumours measuring between 4 and 10 mm in diameter. Since it remains difficult to distinguish between pituitary-dependent Cushing's disease and 'occult' ectopic ACTH-dependent Cushing's syndrome both clinically and biochemically, the role of radiology remains vital.
Department of Academic Radiology, St Bartholomew's Hospital, West Smithfield, London.
J M
JM
Vincent
P J
PJ
Trainer
R H
RH
Reznek
A J
AJ
Marcus
J E
JE
Dacie
P
P
Armstrong
G M
GM
Besser
D000182:ACTH Syndrome, Ectopic / Q000000981:diagnostic imaging*; D000293:Adolescent; D000328:Adult; D000368:Aged; D001984:Bronchial Neoplasms / Q000000981:diagnostic imaging; D002276:Carcinoid Tumor / Q000000981:diagnostic imaging; D002277:Carcinoma / Q000000981:diagnostic imaging; D003528:Carcinoma, Adenoid Cystic / Q000000981:diagnostic imaging; D003480:Cushing Syndrome / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000000981:diagnostic imaging* / Q000378:metabolism; D013953:Thymus Neoplasms / Q000000981:diagnostic imaging; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed