Accessory Adrenal Cortex in Kidney with Clear Cell Renal Cell Carcinoma

Abstract

The accessory adrenocortical tissue is most often encountered around the adrenal glands themselves or sex organs. The frequency of accessory adrenal tissue in kidney is unknown but is apparently rare. We present a case of accessory adrenal gland in kidney involved by primary renal cell carcinoma. A 50-year-old male underwent radical nephrectomy for an incidentally detected renal mass. On pathologic examination, there was an accessory adrenal gland underneath the renal capsule in addition to clear cell renal cell carcinoma in the upper pole. Immunohistochemical staining results (inhibin+, D2-40+, CD10-, and CK-) were consistent with adrenal cortical tissue. It is important to be aware of the existence of accessory pararenal or intrarenal adrenal tissue. Ectopic adrenal tissue with clear cytoplasm may be misdiagnosed as renal cell carcinoma. In addition, a renal cell carcinoma involving accessory intrarenal adrenal tissue may be overstaged as renal cell carcinoma invading adrenal gland.