Thanks for sharing this Interesting case. Based on your gross description, this tumor is composed both solid and cytstic areas. However, your  photomicrographs showed only solid pattern. I wonder what is cytic components look like. My guess will be that cytic part is mucinous cystic glands or mcinous cystadenoma. If my guess is right, then this is a simple "brenner tumor" which is often companied with mucinous glandular components. If cystic part is something else, then I have to reconsider my diagnosis to make sure we exclude other neopleasms.

 翻译杨斌老师的点评：

谢谢分享，根据描述，肿瘤为囊实性，图示实性区，想知道囊性区的形态。我猜是粘液性囊性腺体或粘液性囊腺瘤。如果猜对了，这例就是单纯的"brenner tumor" ，它通常合并粘液性腺样成分。如果囊性区是其他成分，我会重新考虑诊断，以排除其他肿瘤。

上级医院会诊结果:左侧卵巢卵泡膜纤维瘤

免组化:CK(-,上皮区+)

             EMA(-,上皮区+)

            VIM(-/+,性索分化区-)

            Inhibinin(纤维瘤区及上皮区-,性索分化区+)

           CD99(-)

            钙网蛋白(弱+,性索区`)

Thanks for your feedback. To me the unusual and misleading part is "partially cystic" grossly, since it is very unusual to have a cystic component of a so-called "fibroma-thecoma". If this tumor is not cystic, then thecoma, carcinoid and sex-cord tumor will be on the top differentials. This case may be one of those outliers which do not follow the textbook, I guess. Thanks for sharing and I learned a lot from this case.