Cushing's Syndrome – Carcinoid Tumour (CT) Fig. 23.20 Cushing's syndrome: ACTH-secreting carcinoid tumour of the lung demonstrated by CT. The 7mm nodule in the right costophrenic recess represents a small malignant carcinoid tumour secreting ACTH. It could not be seen on either chest radiography or conventional tomography. Removal of the tumour cured the patient. Reproduced by courtesy of the British Medical Journal. See also: • Cushing's Syndrome • Carcinoid Tumours