Of these 4 patients, 1 was suspected of harboring a cavernous sinus adenoma, 2 were found to have lung tumors secreting ACTH, and 1 remained with an undiagnosed etiology.
Ectopic adrenocorticotropic hormone (ACTH) secretion represents 5%-10% of cases of Cushing's syndrome (CS), and approximately 50%-60% of these arise from neuroendocrine lung tumours, including small-cell lung cancer (SCLC).
We presented a case of EAS in which ACTH production by a lung tumour was reduced by metyrapone (MTP) and also reviewed previous cases of ectopic ACTH production suppressed via steroidogenesis inhibition.
To investigate further the morphological evidence for expression of the pro-opiomelanocortin (POMC) gene in neuroendocrine lung tumours, we have examined a series of 46 small cell carcinomas and 13 carcinoid tumours of the lung by in situ hybridization for POMC mRNA using a digoxigenin-labelled oligoprobe.
In addition, larger POMC-like mRNA species between 1200 to 1500 bases were detected in adrenal, testis, ovary, placenta, two pheochromocytomas, and three squamous cell lung tumors.(ABSTRACT TRUNCATED AT 250 WORDS)