Papillary cystadenoma of the epididymis.

The case of a 30-year-old man with papillary cystadenoma of the epididymis is presented. This extremely rare lesion is often associated with von Hippel-Lindau disease, although in this case there were no such signs or symptoms. The gross and microscopic features of this lesion and theories of its origin are reviewed. The constant microscopic features are: efferent duct ectasia with papillary formation, a lining of cuboidal epithelium, often with clear vacuolated cytoplasm, and a stroma of hyalinized fibrous tissue infiltrated by inflammatory cells.