脑室外神经细胞瘤临床病理特征分析

Analysis of Clinical Pathologic Features of Extraventricular Neurocytoma

【目的】探讨脑室外神经细胞瘤（extraventricularneurocytoma，EVN）的病理形态学、免疫表型、鉴别诊断。【方法】对2例EVN的临床表现、影像学、组织形态、免疫组化等进行分析。【结果】2例EVN中男女各1例，年龄为21和32岁。发生在左额叶及鞍区各1例。组织学形态改变：均可见由具有少突胶质细胞样细胞（01igodendrocytelikecells，OLC）构成的蜂窝状结构，局灶或弥漫的神经节细胞分化，毛细血管丰富，血管壁增厚伴透明样变性。2例肿瘤细胞弥漫表达Syn，NSE，NeLlN和S-100，而NF，Olig-2，GFAP灶性阳性，Ki-67阳性细胞〈2％。【结论】EVN与中枢神经细胞瘤相比，组织学形态更加多样，更容易被误诊其他含0LC的肿瘤，特征性的组织学特点及免疫表型有助于鉴别。

[Objective] To explore the pathomorphology, immunophenotypes and differential diagnosis of extraventricular neurocytoma（EVN）. [Methods]The clinical manifestations, image, histomorphology and im- munohistochemistry of 2 patients with EVN were analyzed. [Results] The 2 patients were 1 male and 1 fe- male. The ages of patients were 21 and 32 years old, respectively. The sites of involvement included left fron- tal lobe in one patient and saddle area in one patient. Histomorphology showed that honeycomb structure com- posed by oligodendrocyte like cells（OLC）, focal or suffused ganglion cell differentiation, rich capillary, thick- ened vessel wall with hyaloids degeneration were seen. Syn, NSE, NeuN and S-100 were diffusively expressed in tumor cells of 2 patients. NF, Olig-2 and GFAP were locally positive. Ki-67 positive cells were less than 2%. [Conclusion] Compared with the central neurocytoma, EVN is more diverse in histomorphology, and more easily misdiagnosed as other tumors with OLC. The characteristic histological features and immunohisto- chemical findings may help for differential diagnosis.