K M Colleran1, M R Burge, L A Crooks, R I Dorin. 1. Department of Medicine, Albuquerque VA Medical Center and University of New Mexico School of Medicine, 87108, USA.
Abstract
BACKGROUND: Small cell carcinomas of pulmonary or extrapulmonary origin are neuroendocrine tumors classically associated with ectopic hormone production, particularly ACTH secretion resulting in Cushing's syndrome. However, ectopic Cushing's syndrome has not previously been reported in the setting of small cell carcinoma of the vagina. METHODS: A primary vaginal tumor with hepatic metastases was evaluated with light microscopy. Serum cortisol and plasma ACTH levels were evaluated by radioimmunoassay and immunoradiometric assay, respectively, during a standard high-dose (8 mg) overnight dexamethasone suppression test. RESULTS: Vaginal small cell carcinoma with hepatic metastases was demonstrated. Electrolyte abnormalities, elevated cortisol and ACTH levels, and failure to suppress ACTH secretion during high-dose dexamethasone administration confirmed the diagnosis of ectopic ACTH syndrome. CONCLUSIONS: This case report establishes a clinical association between vaginal small cell carcinoma and ectopic Cushing's syndrome, confirming the neuroendocrine potential of this malignancy and features common to small cell neoplasms originating in other sites.
BACKGROUND: Small cell carcinomas of pulmonary or extrapulmonary origin are neuroendocrine tumors classically associated with ectopic hormone production, particularly ACTH secretion resulting in Cushing's syndrome. However, ectopic Cushing's syndrome has not previously been reported in the setting of small cell carcinoma of the vagina. METHODS: A primary vaginal tumor with hepatic metastases was evaluated with light microscopy. Serum cortisol and plasma ACTH levels were evaluated by radioimmunoassay and immunoradiometric assay, respectively, during a standard high-dose (8 mg) overnight dexamethasone suppression test. RESULTS:Vaginal small cell carcinoma with hepatic metastases was demonstrated. Electrolyte abnormalities, elevated cortisol and ACTH levels, and failure to suppress ACTH secretion during high-dose dexamethasone administration confirmed the diagnosis of ectopic ACTH syndrome. CONCLUSIONS: This case report establishes a clinical association between vaginal small cell carcinoma and ectopic Cushing's syndrome, confirming the neuroendocrine potential of this malignancy and features common to small cell neoplasms originating in other sites.