Large müllerian duct remnant in an adult.

A 20-year-old man presented with a 1-month history of frequently terminal hematuria. Ultrasonography revealed 9 x 5 cm cystic lesion behind bladder and above the prostate. Magnetic resonance imaging showed the midline drop-shaped cyst originating within the prostate gland and separating from the seminal vesicles, in keeping with a müllerian duct remnant. The patient underwent surgical resection of the cyst. The histopathologic staining pattern displayed features consistent with a müllerian duct remnant.