·临床医学图像·
RELA融合基因阳性室管膜瘤
图1 光学显微镜观察显示,肿瘤细胞密度较高,可见假“菊形团”样结构,亦可见分支状血管HE染色×100图2光学显微镜观察显示,肿瘤细胞胞质弥漫性表达L1CAM,胞膜灶性表达L1CAM免疫组织化学染色(EnVision二步法)×200Figure 1Optical microscopy findings showed primary ependymoma with hypercellularity,perivascular pseudorosettes and fine branching vasculature.HE staining×100Figure 2Optical microscopy findings showed the tumor cells were diffusely positive for L1CAM in cytoplasm and focally positive for L1CAM in membrane.Immunohistochemical staining(EnVision)×200
2016年,世界卫生组织(WHO)中枢神经系统肿瘤分类将RELA融合基因阳性室管膜瘤定义为一种以RELA融合基因为特征的幕上室管膜瘤,占儿童幕上室管膜瘤的70%,而在成人中比例较低。发生于颅后窝和脊髓的室管膜瘤无RELA融合基因。组织学形态无特异性,肿瘤呈现标准幕上室管膜瘤结构和细胞学特征,形成假“菊形团”样结构;可见特异性分支状毛细血管排列(图1)或细胞透明样变性。免疫组织化学染色,肿瘤细胞胞质表达胶质纤维酸性蛋白(GFAP)和上皮膜抗原(EMA)、弥漫性表达细胞黏附分子L1(L1CAM),胞膜灶性表达L1CAM(图2),且与RELA融合基因相关性良好。
(天津市环湖医院病理科阎晓玲供稿)
Ependymoma,RELA fusion⁃positive
YAN Xiao⁃ling
Department of Pathology,Tianjin Huanhu Hospital,Tianjin 300350,China(Email:ll934065@126.com)
10.3969/j.issn.1672⁃6731.2017.04.014