恶性外周原始神经外胚层瘤免疫组织化学研究

目的　探讨恶性外周原始神经外胚层瘤 (PNET)的临床病理学特征和意义。方法　采用光镜和免疫组织化学 Dako Envision二步法 ,对 14例外周 PNET进行观察。结果　光镜下肿瘤组织由小圆形细胞构成 ,有 Homer- Wright(H- W)菊心团的排列 ;免疫组织化学标记 14例均有肿瘤细胞膜 CD99(MIC2 )强阳性及肿瘤细胞质 NSE强阳性。并有其他不同神经标记的表达 ,如 Cg A,Syn,MBP,部分病例有 Vim和 S- 10 0的阳性表达。结论　原始神经外胚层瘤 (PNET)是一种高度恶性的小圆形细胞肿瘤 ,诊断与其他骨与软组织的小圆细胞类肿瘤的鉴别诊断具有一定意义 ,PNET的治疗效果与方法仍有待探讨

Immunohistochemical study in malignant peripheral primitive neuro ectodermal tumor

Objective To study the clinicopathological characteristics of the malignant peripheral primitive neuroectodermal tumor(PNET).Method Fourteen cases of PNET were observed by light microscopy and Dako Envision two step method of immunohistochemistry.Results PNET was composed of small round cells and Homer Wright rosette.The positive expression was in 14/14 cases for CD99(MIC2)antibody and 14/14 for NSE;10/14 for chromogranin A;7/14 for synaptophysin;7/14 for MBP.Conclusion PNET is a rare highly malignant tumor of small round cells.The diagnosis of PNET is established by immumohistochemistry.The differential diagnosis of small round cell tumors is significant in a sense.The treatment of PNET awaits further study.