Ectopic adrenal cortical adenoma in the spinal region: case report and review of the literature.

Ectopic adrenal cortical neoplasms are extremely rare; few involve the central nervous system (CNS). We report a 17-month-old girl with spinal adrenal cortical neoplasms. She was unable to crawl or stand and was irritable at night. Her appearance was asymmetrical; the right side of her face and her lower right leg were enlarged. In addition, she manifested hyperplasia of the thymus, fibrous hyperplasia of the bladder, and hamartoma in the liver. However, all abnormalities were asymptomatic. Magnetic resonance imaging (MRI) revealed well-circumscribed masses within the dura mater at the T12-L1 and L3-L4 level. Histology disclosed that the lesions were composed of sheets and nests of round and polygonal cells with mostly round regular nuclei; eosinophilic to clear cytoplasm was abundant. Immunohistochemically, the tumor cells were strongly positive for inhibin-alpha, positive for synaptophysin and vimentin, and negative for GFAP, EMA, S-100, NSA, and chromogranin A. In addition, the nuclei stained positive for steroidogenic factor 1 (Ad4BP/SF-1), which is involved in adrenal steroidogenesis. This case confirms the occurrence of adrenocortical adenoma in the CNS. We suggest that this tumor should be considered in the differential diagnosis of CNS tumors.