Total laparoscopic resection of primary large retroperitoneal teratoma resembling an ovarian tumor in an adult.

Whereas most teratomas occur in the ovaries and testes of adolescents, they can be found in midline structures such as sacrococcygeum (congenitally), anterior mediastinum, retroperitoneum, and the pineal gland. Primary retroperitoneal teratomas are extremely rare in adults. A 27-year-old woman was referred to our hospital because of an incidentally found pelvic mass, considered to be an ovarian tumor by ultrasonography. Computed tomography strongly suggested a retroperitoneal cystic tumor because of anterior displacement of retroperitoneal organs. The large retroperitoneal mature teratoma was successfully resected laparoscopically without complication. In this case, despite a large tumor size and its approaching the rectum, total laparoscopic resection was the most feasible surgical choice.