術前に予測して鏡視下に摘出しえた、ダグラス窩に見られた卵巣外成熟囊胞性奇形腫の一例

抄録

  Mature cystic teratomas derived from extragonadal lesions are rare. We report a case of extragonadal mature cystic teratoma (EMCT) in the pouch of Douglas (POD), which was predicted preoperatively and successfully resected by performing laparoscoic surgery. A 35-year-old woman was incidentally diagnosed with a mass measuring 6 cm in diameter in the right pelvis on ultrasonographic examination. Magnetic resonance imaging (MRI) findings were suggestive of mature cystic teratoma. Both normal ovaries were found adjacent to the mass. We considered the possibility of EMCT, and performed laparoscopic surgery.

  Intraoperatively, the cyst was found in the POD and both ovaries appeared normal. There were violin string-like adhesions between the cyst wall and the back of the uterus, right ovary, and serosa of the rectum. We dissected the adhesions with the rectum with the help of a gastroenterological surgeon, and dissected the other adhesions easily ourselves. The patient had an uneventful postoperative course and was discharged on the fourth post-operative day. Pathological examination of the resected mass revealed the mass to be EMCT.

  Only approximately 20 cases of EMCTs in POD have been reported till date. There are several hypotheses to explain their etiopathogenesis. We hypothesize that auto-amputation could be the mechanism that resulted in EMCT in this case. Though EMCTs are rare, we should consider performing detailed preoperative evaluations with EMCT as a differential diagnosis. Subsequently, we can plan an appropriate surgical approach beforehand, and perform laparoscopic surgery safely.