Adrenocortical adenoma with rhabdoid features

Abstract

We report a case of an aldosterone producing adrenocortical adenoma with rhabdoid features in a 16-year-old girl. Grossly, the tumor measured 30 mm in diameter and weighed 24 g. Histologically, the tumor was composed of approximately equal parts of tumor cells with rhabdoid features arranged in a solid and trabecular pattern and cells characterized by compact eosinophilic cytoplasm, solid growth with focal necroses, and increased mitotic activity. The lipid-rich tumor cells with ample clear vacuolized cytoplasm represent a minor component. Immunohistochemically, all the tumor cells showed the same results and were positive for vimentin, synaptophysin, Melan A, and α-inhibin. Cytokeratin CAM 5.2 was positive only focally. Chromogranin A, actin, α-actin, S100 protein, EMA, and cytokeratin AE1/AE3 were negative. Rhabdoid features have been described in many tumors of variable histogenesis; however, to the best of our knowledge, the presence of rhabdoid phenotype has never been described in either adrenocortical adenoma or carcinoma.