A case of an omental mature cystic teratoma that was removed with laparoscopic operation

Abstract

Mature cystic teratomas commonly arise from the ovaries. In addition to ovaries, these teratomas are the known to originate from the testis, sacrococcygeal region, retroperitoneum, mesentery, mediastinum, and intracranial space. However, a mature cystic teratoma of the omentum is rare. We report a case of an omental mature cystic teratoma that was preoperatively diagnosed to have an ovarian origin and was removed with laparoscopic operation. A 39-year-old woman, gravida 1 para 1, visited our hospital owing to a diagnosis of ovarian tumor. Magnetic resonance imaging (MRI) revealed a cystic tumor of 6 cm diameter, adjacent to the left front of the uterus. The right ovary was also normal sized, whereas the left ovary was not identified in the MRI image. Laparoscopic operation was indicated for the removal of the left ovarian teratoma. Intraperitoneal observation revealed a cystic tumor, fibrously attached to the omentum and had no association with both ovaries. The feeding vessel to the omental tumor was not clearly identified. The right ovary had a normal appearance, and the left ovary was atrophic with a streak appearance. There were no other tumors nor other disseminated lesions in the peritoneum. The laparoscopic operation was completed with the resection of the omental tumor. The postoperative pathological result indicated a mature cystic teratoma of the omentum. The literature reports on omental mature cystic teratomas in Japan are limited to a dozen cases. There are two hypotheses on the occurrence of a teratoma from the omentum: primary origin from the omental supernumerary ovary and ovarian origin with autoamputation. To our knowledge, this is the first report on the laparoscopic management of an omental teratoma in Japan. Mature cystic teratomas can cause malignant transformation and should be treated carefully and surgically removed. [Adv Obstet Gynecol, 68 (1) : 29-35, 2016 (H28.2)]