原发性中枢神经母细胞瘤的MRI表现

MRI manifestations of primary cerebral neuroblastoma

目的探讨中枢神经母细胞瘤的MRI表现特点,以提高对该病的认识。方法回顾性分析经手术病理证实的6例神经母细胞瘤的MRI表现,并与手术、病理相对照。结果6例肿瘤分别位于额叶2例、顶叶1例、胼胝体1例、侧脑室1例、松果体1例。肿瘤体积多较大,常伴坏死、囊变或出血。肿瘤实性部分T1WI呈等或稍低信号,T2WI呈稍高信号,增强扫描均明显强化。肿瘤组织镜下均以小圆形、未分化细胞组成,核浓染,胞浆稀少,部分瘤细胞呈不典型菊形团排列,瘤细胞团之间可见小血管明显增生。免疫组化检查6例均有神经元特异性烯醇化酶(NSE)、突触素(Syn)、神经微丝蛋白(NF)表达,均无胶质纤维酸性蛋白(GFAP)表达。结论中枢神经母细胞瘤的MRI表现有一定的特征性,最后诊断有赖于病理和免疫组化。

Objective To investigate the MRI features of primary cerebral neuroblastoma. Methods MRI manifestations of 6 primary cerebral neuroblastomas diagnosed via operation and pathological examination were retrospectively analyzed. Results The location of 6 tumors were in the frontal lobe （n=2）, parietal lobe （n= 1）, corpus callosum （n= 1）, lateral ventricle （n= 1）, pineal （n= 1）, respectively. The tumors were often quite large in volume with some cystic and necrotic areas. Intratumoral hemorrhage was occasionally seen. Solid components of tumors were isointense or mild hypointense on TlWI and mild hyperintense on T2WI, and were contrast enhanced significantly. Microscopically neuroblastomas were composed of sheets of small, undifferentiated cells with hyperchromatic nuclei, scanty cytoplasm. Atypical Homer-Wright rosettes and significant hyperplastic small blood vessel were usually presented. All the tumors expressed NSE, Syn and NF, and did not express GFAP. Conclusion The MR imaging of primary cerebral neuroblastoma have some characteristics, but the last di- agnose relies on pathological and immunohistochemical examinations.