Ectopic Cushing's syndrome and pulmonary carcinoid tumour identified by [111In-DTPA-D-Phe1]octreotide.

The differential diagnosis and management of Cushing''s syndrome remain difficult, particularly for ectopic adrenocorticotropin (ACTH) syndromes resulting from small bronchial carcinoids. We report the case of a 41-year-old man with ectopic ACTH-dependent Cushing''s syndrome. Two computed tomography scans of the thorax were normal and magnetic resonance imaging of the chest showed a 6-mm hyperintense T1-weighted area close to the left pulmonary hilus, interpreted as probably vascular by the radiologists. An [111In-DTPA-D-Phe1]octreotide scintigraphy scan demonstrated a positive image for somatostatin receptors in exactly the same location and surgery confirmed the presence of a small ACTH-secreting carcinoid tumour in the upper left lung lobe which was resected. Surgery cured the hypercorticism of the patient. The differential diagnosis of Cushing''s syndrome and the procedure for localisation of an ACTH source are discussed.     

Anterior pituitary function after adrenalectomy in patients with Cushing's syndrome.

We assessed anterior pituitary function in five patients with Cushing''s syndrome before and after the removal of cortisol-secreting adrenal adenomas. Before surgery, all patients lacked response of growth hormone to hypoglycaemia, four had low responses of thyrotrophin to thyrotrophin releasing hormone, three had hypogonadism and two had low prolactin reserve. After successful removal of the adrenal adenoma, all patients developed postoperative hypoadrenocorticism and recovered all impaired anterior pituitary hormones within a period of 3 months. Our results point to a direct inhibiting action of glucocorticoids at the pituitary level as the explanation for the impaired anterior pituitary function. Moreover, direct gonadal suppression by glucocorticoids may be an additional mechanism of hypogonadism in some patients.     

Mediastinal carcinoid tumour with unusual manifestations

A rare case of mediastinal carcinoid tumour with superior vena cava obstruction, and osteolytic as well as osteoblastic secondaries in the bones is described. The relevant literature is reviewed.     

A patient with co-existing bronchial carcinoid tumour and bilateral phaeochromocytoma.

We report a 31-year-old Chinese man with bronchial carcinoid tumour and bilateral phaeochromocytoma. His sister also gave a history of bilateral carotid body paraganglioma. This case demonstrates the importance of screening for other endocrine disorders in patients with foregut carcinoid tumours.     

Lung carcinoid related Cushing's syndrome: report of three cases and review of the literature

Three patients with lung carcinoid related Cushing''s syndrome (LCRCS) treated at Frenchay Hospital, Bristol between 1984 and 1994 are described. The first patient presented with hyperpigmentation 13 years after bilateral adrenalectomy. The second patient had no recurrence or metastases 14 years after removal of a typical carcinoid tumour. The last patient survived nine years after diagnosis of liver metastasis. The possibility of LCRCS should be considered in every patient proved to have Cushing''s disease and bilateral adrenal enlargement on abdominal computed tomography. Biochemical sets of investigation (for example, adrenocorticotrophic hormone (ACTH) stimulation, dexamethasone suppression, and metyrapone response) could be misleading and should not be relied upon solely. Search for an ectopic ACTH source should be called off only when ACTH has been demonstrated in the surgically removed specimen, and most importantly, when the serum ACTH concentration returns to normal after surgery. Lung carcinoid tumours are compatible with long survival, and liver metastasis could prove indolent and slowly growing.


     

Cutaneous scleroderma in association with carcinoid syndrome.

A case of scleroderma in a woman with carcinoid syndrome is described and the similarities between our case and those in the literature are reviewed. The carcinoid tumours were all of midgut origin and liver metastases were present. All subsequently developed fibrotic heart disease and none had clinical features or autoantibodies suggestive of systemic sclerosis. The association between carcinoid syndrome and particular features of scleroderma is likely to be more than fortuitous.     

Bilateral adrenal myelolipomas with Cushing's syndrome

A 24-year-old woman with non-pituitary dependent Cushing's syndrome was found to have bilateral adrenal myelolipomas at surgery. These benign tumors consist of bone marrow and fat and are uncommon incidental findings that are discovered by computed tomography. Myelolipomas have rarely been associated with Cushing's syndrome, but the cause of the syndrome has not always been defined, because the reports preceded modern diagnostic methods. Careful examination of the adrenal glands from our patient showed a fusion of myelolipoma elements and adrenal cells without distinct adenomas or the typical nodular pattern of adrenal hyperplasia. This report suggests that adrenal myelolipomas and atypical hyperplasia of the zona fasciculata may be anatomically and functionally related.     

Diagnostic difficulties in periodic Cushing's syndrome.

A 22-year-old black woman presented with symptoms suggestive of Cushing''s syndrome three years after chemotherapy for a presumed teratoma with cervical lymphadenopathy. Initially, the absence of clinical signs and the demonstration of two normal 24 h urinary free cortisols appeared to exclude the diagnosis, but an ectopic adrenocorticotropin-producing thymic carcinoid was subsequently removed surgically. Cushing''s syndrome due to ectopic adrenocorticotropin production can be difficult to diagnose, particularly if there is periodic hormonogenesis.     

Adrenal incidentaloma: subclinical Cushing's syndrome.

Adrenal incidentalomas present a significant differential diagnostic challenge. All patients with an incidentally discovered adrenal lesion should be carefully considered and re-evaluated to exclude extra-adrenal malignancy. Tumours with hypersecretory syndromes require excision, whilst those tumours more than 6 cm in size, particularly if they exhibit other features of malignancy on computed tomography (CT), magnetic resonance imaging (MRI) or scintigraphy, should also be excised. In all cases screening for phaeochromocytomas should be performed, and in the context of hypertension and spontaneous hypokalaemia, a primary aldosterone-secreting tumour requires exclusion. However, the natural history and treatment regimens for those individuals demonstrating ''subclinical Cushing''s syndrome'' is far from clear. Size, as determined by CT or MR scanning, does not in itself reliably distinguish benign from malignant disease. Scintigraphy may be a useful adjunct, with discordant patterns suggesting malignant disease. Fine needle aspiration should not routinely be used but may be useful in cases of doubt about other extra adrenal malignancy.