Abstract
Retroperitoneal mucinous cystadenomas are rare lesions (less than 50 reported) characterized by presence of ovary like stroma of unknown origin. However, germinal component of ovary has never been found in them. The pancreas occasionally gives rise to mucinous cystadenomas, but they are always intrapancreatic. We report a unique case of a rare retroperitoneal mucinous cystadenomas with presence of ovarian follicles in a 45-year-old lady who presented with an abdominal mass. This was successfully excised. Though retroperitoneal mucinous cystadenomas are rare, presence of ovarian follicle (germ cell) in them has never been reported before.