室管膜瘤的脂肪生成分化很少发生，报道病例很少。分级仅根据组织形态学进行，并且此类室管膜瘤中未描述分子亚型。新的分子分类将室管膜瘤分为九个不同的亚组，其中幕上位置的肿瘤通常表现出C11orf95-RELA、YAP1-MAMLD1和YAP1-FAM118B融合蛋白。一名 46 岁女性因头痛和右侧截瘫就诊。放射学检查显示左侧顶枕部有一个巨大的轴内肿块病变，组织学和免疫组织化学证实为间变性室管膜瘤，伴有广泛的脂肪生成变化。免疫组织化学和超微结构研究证实了肿瘤的室管膜起源。 C11orf95-RELA、YAP1-MAMLD1 和 YAP1-FAM118B 融合蛋白的分子研究结果为阴性。这是第一个关于融合阴性幕上间变性室管膜瘤与脂肪生成分化的文献。这一新发现需要通过类似研究进一步证实，以确定其对疾病结果的影响。

Lipogenic differentiation in ependymoma is an infrequent occurrence with very few reported cases. The grading was done solely based on the histomorphology and molecular subtyping was not described in such ependymomas. New molecular classification divided ependymomas in nine different subgroups, of which supratentorial location tumor usually exhibits C11orf95-RELA, YAP1-MAMLD1, and YAP1-FAM118B fusion proteins. A 46-year-old female presented with headache and right-sided parapresis. Radilogy revealed a large intraxial left parietooccipital mass lesion, which histologically and immuohistochemically confirmed as anaplastic ependymoma with extensive lipogenic changes. The ependymal origin of the tumor was corroborated by the immunohistochemistry and ultrastructural studies. Molecular studies for C11orf95-RELA, YAP1-MAMLD1, and YAP1-FAM118B fusion proteins were negative. This is the first documentation of fusion negative supratentorial anaplastic ependymoma with lipogenic differentiation. This novel finding needs further reinforcement by similar studies to identify its impact on the disease outcome.