A case of benign retroperitoneal cyst of Müllerian type in kidney transplant patient.

Müllerian cysts of the retroperitoneum, which considered to be a subtype of urogenital cysts, are extremely rare disease entities. Herein we have presented successful excision from a second kidney transplantation from a brain-dead donor to a 38-year-old woman with previous kidney graft failure. During the second cadaveric kidney transplantation operation, two fist-sized cysts were found in the left retroperitoneal pelvic space extending from the left common iliac artery to the prevesical region, which compromised the iliac vessels for vascular anastomosis. After complete cyst excision, vascular anastomoses were performed. Histologically, the cysts were lined with benign Müllerian-type epithelium. We report a rare case of benign retroperitoneal cyst of the Müllerian type, which was incidentally found during kidney transplant surgery.