Elevation of Serum CA-125 in Mucinous Cystadenoma of the Ovary with Torsion: A Rare Occurrence and Review of the Literature

Aim: Benign neoplasms of the ovary originating from epithelial tissue are common tumors in adult women. They are, however, rarely seen in children or adolescent girls with elevation of serum carbohydrate antigen125 (CA-125). The present report describes a rare case of premenarchal women with a giant mucinous cystadenoma (MCA) of the ovary with torsion complicated with elevation of serum CA-125. Case: A 15-yearold, premenarchal, previously healthy girl was referred to our hospital with a 2-week history of left lower abdominal pain. Physical examinations showed a firm and mobile mass with tenderness in the left lower quadrant. Tumor markers showed CA-125 at 124.1 U/ml. An enhanced computed tomography scan showed a multiloculated tumor that was partly solid, compressing the small intestine, uterus, and urinary bladder, but no signs of organ invasion, lymph node swelling, or ascitis. Via a lower transverse incision, the right Fallopian tube was observed to have twisted 1620 ̊ counterclockwise, and a tense cyst measuring 22.0 × 12.0 × 10.5 cm and weighing 1.78 kg was found in the right ovary. Release from torsion and unilateral salpingooophorectomy with tumor removal was performed because blood flow to the right Fallopian tube did not improve after torsion release. The histopathological findings showed an MCA of the ovary without cell dysplasia. The patient did not receive adjuvant chemotherapy following surgery. There was no evidence of recurrence at 2 years. Disucussion: We need to consider MCA of the ovary when there is elevation of the serum CA-125 and an ovarian mass.