Vladimír Bartoš, Barbora Šafeková, Dušan Pokorný
Primary tumours of the epididymis are rare and comprise about 5 % of all intrascrotal neoplasms. Most of them are benign lesions, with a papillary cystadenoma (PCA) being the second most common type. The authors describe a 20-year-old man with an unremarkable medical history, who was diagnosed to have a solid cystic tumour mass arising on the upper pole of the left epididymis. Microscopically, it consisted of the cysts of various sizes filled with an acellular eosinophilic material. The epithelium was composed of cuboidal and columnar cells with cytoplasmic clearing, which formed prominent intracystic papillary projections. Immunohistochemically, they were reactive for CK7 and PAX-8 and negative for RCC antigen and AMACR. Histopathology and immunophenotype of the lesion were consistent with PCA of the epididymis. Although epididymal PCA occurs only sporadically, it should be included in the differential diagnosis of intrascrotal paratesticular tumour lesions. Though it is a prognostically favourable benign tumour, a bilateral involvement may be one of the features of von Hippel-Lindau disease.