Metastatic carcinoid tumor fo the lung producing Cushing's syndrome.

The clinical and pathologic features of a patient with Cushing's syndrome and a primary pulmonary tumor are presented. The Cushing's syndrome presented almost one year after removal of the lung tumor and chemotherapy for cerebral metastasis. The cause of the Cushing's syndrome was unclear, but failure to suppress with high-dose dexamethasone therapy indicated it was due to a primary adrenal tumor or ectopic ACTH production. Surgery revealed a large tumor in the right adrenal with a much smaller tumor in the left adrenal gland, and metastatic bronchial carcinoid with Cushing's syndrome due to ectopic ACTH production was diagnosed. The clinical significance of this is discussed with regard to routine light microscopy and patients who present with endocrine syndromes and tumors of questionable cause.