Oat cell carcinoma of the urinary bladder with ectopic adrenocorticotropic hormone production

A case of primary oat cell carcinoma of the urinary bladder with ectopic adrenocorticotropic hormone (ACTH) secretion in a 55-year-old woman is reported. Cystoscopy revealed a large necrotic tumor in the bladder; the tumor was partially electroresected. At autopsy, a large residual tumor infiltrating the wall of the bladder was found. It had metastasized to the lymph nodes, left ovary, liver, spinal canal, bone marrow, and hypophysis. Bilateral adrenocortical hyperplasia was found. Microscopically, the tumor was identical morphologically to oat cell carcinoma, and the cells contained argyrophilic hormone granules and immunohistochemically demonstrable ACTH. Apparently, oat cell carcinomas with endocrinologic activity have not been reported previously in the urinary bladder.