腹腔鏡下生検が確定診断に有用であった横隔膜内膜症の一例

抄録

　Endometriosis is a benign gynecological disorder characterized by the implantation of ectopic endometrial tissue outside the uterine cavity. Endometriotic lesions are commonly found in the pelvic cavity. Extra-pelvic endometriosis occurs much less frequently, and diaphragmatic endometriosis is estimated to affect 0.19-1.5% of all endometriosis cases.

　We present a case of diaphragmatic endometriosis diagnosed by laparoscopic surgery. A 45-year-old woman was referred to our hospital for the investigation of a right ovarian tumor. Enhanced computed tomography incidentally revealed nodular lesions in the right diaphragm and left pelvis, which suggested malignant dissemination. Positron emission tomography showed slightly abnormal fluorine-18-deoxyglucose accumulation. A surgical biopsy was required to confirm the diagnosis, and laparoscopic surgery was performed. Intraoperative findings suggested endometriosis, and a diaphragmatic mass was partially resected. Histopathological and immunohistochemical findings were consistent with endometriosis without malignant transformation.

　It is quite difficult to make a preoperative diagnosis of diaphragmatic endometriosis due to the lack of specific radiological characteristics. This case highlights the importance of considering endometriosis in the differential diagnoses when a diaphragmatic lesion is found, and the efficacy of laparoscopic biopsy to confirm the diagnosis.