Bilateral Mature Ovarian Teratoma with Torsion in a Premenarchal Girl.

Mature cystic teratoma is the most common type of ovarian tumor in children. Adnexal torsion is the main complication of mature ovarian teratoma. The synchronous bilateral incidence of mature cystic teratoma in premenarchal girls is known to be rare. However, the incidence of adnexal torsion is higher in young girls. A 10-year-old girl presenting with acute abdomen was managed by emergency laparotomy. Bilateral mature ovarian teratoma with adnexal torsion of the right ovary was found. The right ovarian tissue was not viable due to torsion and an oophorectomy was necessary. Cystectomy with preservation of the ovarian tissue of the left ovary was performed. Histopathological diagnosis was bilateral synchronous mature teratoma with necrosis of the right adnexa. Although the risk of malignancy of torsed ovaries and mature teratomas in premenarchal girls is low, their removal is recommended to prevent adnexal torsion. Decision between ovarian tissue sparing surgery or oophorectomy depends on the risk of malignancy, fertility preservation and the avoidance of early menopause.