脑回状神经鞘瘤的临床病理学研究

目的探讨脑回状神经鞘瘤(GSW)的临床病理学特征。方法对4例GSW进行临床特征、光镜表现、免疫组化情况及超微结构进行观察。结果 4例患者中男性、女性各2例,均位于头颈部(颈部及腮腺各2例),为缓慢生长的无痛性或轻微触痛,境界清楚的包块。大体标本肿瘤包膜完整,直径2~4 cm,切面呈灰黄色。镜下肿瘤组织呈实性片状分布,由圆形或卵圆形细胞构成,胞浆丰富、红染,胞核排列紧密,肿瘤细胞形成不规则梁索状或分枝状并相互吻合,极性明显且富于胞浆的突起分布于梁索状或分枝状胞核两侧,形成脑回状外观。免疫组化显示GSW表达Vimentin、S-100蛋白、CD56、Bcl-2、PGP9.5,弱阳性表达CD99,不表达calponin、β-catenin、desmin、CD34、MSA、SMA、GFAP、collagen IV、Cyclin D1、laminin、AE1/AE3及p63。电镜下显示GSW细胞具有神经鞘细胞特征。结论 GSW具有独特的形态学表现,其免疫表型及超微结构特征均具有神经鞘细胞分化的特点,因此推测该肿瘤可能为神经鞘瘤的一种新亚型。

Clinicopathologic study of gyriform schwannoma

Objective To investigate the clinical and pathological features of gyriform schwannoma(GSW).Methods The clinical features, performance of light microscopy, immunohistochemistry and ultrastructure of 4 cases of GSW were observed.Results There were two males and two females.Each of the 2 cases was located in the head and neck.GSW was a slowly growing painless mass or slight tenderness with clear boundary.The capsule of the tumor was integrity, with diameter of 2-4 cm, and the section was grayish yellow.The tumor tissues distributed as solid flakes, were composed of round or oval cells.The cytoplasm was rich and red, and the nuclei were arranged closely.Tumor cells were matched with each other in irregularly trabecular or branched manner.Protuberances with obvious polarity were distributed in trabecular or branched nuclei on both sides, forming gyriform appearance.Immunohistochemical method showed that there were expressions of Vimentin, S-100 protein, CD56, Bcl-2 and PGP9.5,with diffuse weakly-positive expression of CD99,and no expression of calponin, β-catenin, desmin, CD34, MSA, SMA, GFAP, collagen IV, CyclinD1, laminin, AE1/AE3 and p63.The electron microscopy observation showed that tumor cells possessed features of nerve sheath cells.Conclusion GSW has unique morphologic features and its immunophenotype and ultrastructural characteristics both possess characteristics of nerve sheath cell differentiation.Therefore, it is presumed that GSW is a new subtype of schwannoma.