[Papillary cystadenoma of the epididymis accompanied by testicular atrophy: one case report].

Papillary cystadenoma of the epididymis is a rare benign tumor, accounting for only 4 per cent of all epididymal tumors. Histologically, it can be confused with metastatic renal cell carcinoma. This extremely rare lesion may occur sporadically or as a manifestation of von Hippel-Lindau(VHL) disease. The present paper reported a case of papillary cystadenoma accompanied by testicular atrophy with no signs of VHL syndrome or infertility. To date, no similar case was reported in the literature. The tumor measured 5.0 cm x 4.0 cm x 4.0 cm and was located in the right epididymis. Histopathologic examination of a surgically removed specimen indicated a primary papillary cystadenoma. Histomorphologically, these tumors are characterized by cysts with colloid-like contents and papillary formations of light epithelium. Since metastatic renal cell carcinoma may be histologically similar to papillary cystadenoma, the importance of long-term urologic follow-up for possible presentation of renal cell carcinoma is discussed.