閉経後に生じた単房性卵巣腫瘍茎捻転を良性の診断で腹腔鏡下に摘出し、後に卵巣高異型度漿液性癌と診断した１例

抄録

　Ovarian torsion is frequently found in benign cases of non-adhered ovarian tumors. When only a simple cyst without surface nodules is detected by preoperative ovarian imaging, we tend to classify the tumor as benign. We herein report a case of a simple ovarian cyst that presented as ovarian torsion and was found to be a high-grade serous carcinoma by laparoscopic adnexectomy in a postmenopausal woman.

Case: A 74-year-old woman (postmenopausal age: 55 years, gravida 1 para 1) was referred to our hospital because of a right ovarian tumor detected by abdominal computed tomography. Magnetic resonance imaging showed a 12-cm simple cyst, and no findings suggestive of malignancy, such as a nodule on the tumor surface, were detected. The levels of tumor markers were as follows: CA 125, 19 U/ml and CA19-9, 9.9 U/ml. A right ovarian laparoscopic adnexectomy was performed because the tumor was considered benign. Laparoscopic findings showed that the tumor was twisted twice around the ovary ligament and no adhesion or peritoneal dissemination to the surrounding organs were evidenced. Pathological examination revealed a high-grade serous carcinoma of the ovary. At a later date, we performed staging laparotomy and no carcinoma cells were found in the organs. Therefore, we classified the ovarian cancer as stage IA according to the International Federation of Gynecology and Obstetrics.

Conclusion: We reported a case of a simple ovarian tumor presenting as ovarian torsion detected as a carcinoma by laparoscopic adnexectomy in a postmenopausal woman. Ovarian torsion occurrence should be considered a risk factor for postoperative ovarian carcinoma.