室管膜肿瘤组织分化谱系及分子分型进展

Histologic spectrum and molecular subgroups of ependymal tumors

室管膜肿瘤是临床较少见的神经上皮组织肿瘤,组织分化谱系多样,除目前世界卫生组织(WHO)承认的亚型和变异亚型外,尚有许多特殊变异亚型或组织分化模式,如巨细胞型、黑色素型、印戒细胞型、脂肪/空泡化生型、软骨化生(伴或不伴骨形成)型、嗜酸细胞型、上皮样等。病理科医师应注意上述特殊变异亚型的识别和鉴别诊断。基因组学和DNA甲基化谱系研究将室管膜肿瘤分为9种分子亚型,RELA融合基因阳性室管膜瘤被2016年WHO中枢神经系统肿瘤分类作为室管膜瘤的独特分子亚型。尽管分子亚型对预后的评价优于传统组织学分级,然而如何将分子遗传学特征与组织分化谱系整合尚待进一步深入研究。

Ependymal tumors are relatively infrequent neuroepithelial neoplasms,but they have a wide and complex histologic spectrum including subtypes and variants recognized by the current Word Health Organization （WHO）,and some special morphologic variants or growth patterns such as giant cell morphology,melanin differentiation,signet-ring,fat or vacude metaplasia,cartilage metaplasia with or without bone formation,oncocytic,epithelioid,and so on.Pathologists need to pay attention to identification and differential diagnosis of these special morphologic variants.Genomic and DNA methylation profiling studies have defined nine distinct molecular subgroups of ependymal tumors.RELA fusion-positive ependymoma has now been designated as one of the distinctive molecular variants of ependymoma by 2016 WHO classification of central nervous system tumors.Risk stratification by molecular subgrouping is superior to histological grading.However,how to integrated molecular genetic features into the histological spectrum need to be further researched.