Virilizing ovarian dermoid cyst with leydig cells.

BACKGROUND: The clinical observation of virilization is a rare finding that has a number of possible explanations. Overall, ovarian tumors causing virilization are exceedingly rare and mostly occur in post-menopausal women. In fact, there are no reported cases of virilization from a testosterone-producing ovarian dermoid in the adolescent female age group. The most frequent germ cell tumor derived from the ovaries is the benign cystic teratoma (dermoid) which accounts for 25% of all ovarian neoplasms. Teratomas consist of tissues that recapitulate the ectoderm, endoderm, and mesoderm. Usually the tumors are asymptomatic, but they occasionally can cause severe pain if there is torsion or if sebaceous material perforates the cyst wall, leading to reactive peritonitis. CASE: A 12-year-old female was found to have a large 3 5 x 19 x 12 cm ovarian mature cystic teratoma arising from her right ovary. The patient also displayed evidence of masculinization demonstrated by a deepening voice and clitoromegaly. The dermoid was producing large amounts of testosterone from a nest of Leydig cells found pathologically in the mass. CONCLUSION: Benign cystic teratomas can produce active hormones, albeit rarely. This is a finding important to consider when ovarian cystectomy is performed for removal of a benign cystic teratoma.