卵巣類内膜境界悪性腫瘍の1例

A case of endometrioid borderline ovarian tumor

卵巣類内膜腫瘍は良性の子宮内膜症性嚢胞，悪性の類内膜癌として認められることが多く，類内膜境界悪性腫瘍は極めてまれである。異型のある子宮内膜腺上皮類似の細胞からなり，間質への明らかな浸潤は欠如する腫瘍である。今回，卵巣類内膜境界悪性腫瘍の1例を経験したので報告する。

The patient was a 60s woman. A large pelvic mass was pointed out by a checkup. Pelvic MRI revealed a solid and cystic mass measuring 18 cm in the left ovary. Solid regions showed low to high signal intensity on T2-weighted image. Although a part of solid region showed moderate high intensity on diffusion-weighted imaging, the mean ADC value slightly increased in the whole solid region. Hemorrhage indicating endometriosis was observed on T1-weighted image. She was finally diagnosed as endometrioid borderline ovarian tumor. In this case, diffusion weighted image and mean ADC value of the whole solid region were useful for the diagnosis of borderline tumor.