A case of intratesticular endometrioid papillary cystadenocarcinoma.

We report a case of intratesticular endometrioid papillary cystadenocarcinoma. A 73-year-old man was admitted for a painless right scrotal swelling. Ultrasonography and computed tomography revealed a large cystic mass in the right testis. Right scrotum puncture revealed xanthochromic fluid with negative cytology. Three months later, follow-up computed tomography showed enlargement of the cystic mass. Right high orchiectomy was performed because a testicular malignancy was suspected. The pathological diagnosis was endometrioid papillary cystadenocarcinoma, and the cells were strongly positive for the estrogen and progesterone receptors. Testicular neoplasms resembling common ovarian-type epithelial tumors are very rare. This is the first report of endometrioid papillary cystadenocarcinoma of the testis.