Answer: Clear cell renal cell carcinoma, Metastatic to adrenal gland

Histology: Although some of the histologic features raise the differential diagnosis of a primary adrenal cortical neoplasm, the clinical history of a prior radical nephrectomy, the immunophenotype (negative Melan A, and synaptophysin) together with the presence of charcteristic “bleeding” follicular structures lined by cells containing optically cleared cytoplasm all favor a metastatic renal cell carcinoma. The presence of a prior Fuhrman grade 3 RCC was histologically confirmed.

Discussion: Adrenal Gland is a common site for metastatic tumors from variable primary sites. Lung and breast primaries account for 60% of cases followed by GI tract, renal and melanoma primaries. Additional markers that can be helpful in establishing an adrenal primary origin include positive Inhibin and Calretinin and negative pancytokeratin (in some cases) and EMA reactions.