A Paratesticular Multicystic Tumor of the Tunica Vaginalis Testis as Rare Paratesticular Cystadenoma.

The cystadenoma of the testis and paratestis arising from an unequivocal oviduct-like structure, which is morphologically almost identical with those of the ovarian surface epithelium. These are very rare benign tumors of young adults. They present as asymptomatic cystic lesions. Bilateral paratesticular cystadenomas are strongly associated with von Hippel-Lindau syndrome and correlate with infertility. It is a neoplasm with low malignant potential. Most cystadenomas are benign but a few cases of malignant transformation of embryonic remnants have been reported in the appendix testis, including cases of adenocarcinoma, cystadenocarcinoma, and a low malignant müllerian-type epithelial tumor. We report the rare case of a 63-year-old man with a paratesticular multicystic cystadenoma of the male adnexa without association to von Hippel-Lindau disease.