鼻NK/T细胞淋巴瘤的免疫表型、EBV感染及TCRγ基因重排的检测

Immunophenotype and Epstein-Barr Virus Infection and Detection Rearrangement of T Cell Receptor γ(TCRγ) Gene in Nasal NK/T-cell Lymphoma

目的检测鼻NK/T细胞淋巴瘤(NK/TCL)的免疫表型、EBV感染及TCRγ基因重排,为诊断和鉴别诊断提供依据。方法收集诊断鼻NK/TCL48例患者石蜡包埋标本,用免疫组化SP法标记LCA、CD79α、CD20、CD56、CD3、CD45RO及EBV抗体研究其免疫表型;EBER探针原位杂交方法检测EBV编码的小分子RNA(EBER);聚合酶链式反应扩增方法检测TCRγ基因重排。结果48例鼻NK/TCL均表达LCA,CD3、CD45RO、CD56和EBV阳性率分别为44%、52%、73%和19%,CD79α和CD20均阴性;EBER阳性率为81%;TCRγ基因重排阳性率为19%。结论鼻NK/TCL免疫表型不一致,并非所有病例CD56阳性,石蜡切片中CD3阳性定位于细胞质;EBER在肿瘤细胞中高表达,提示它们可能为NK细胞来源;部分TCRγ基因重排阳性病例应为鼻NK样T细胞淋巴瘤。

Objective To explore the immunophenotype and Epstein-Parr Virus（EBV） infection of nasal NK/T cell lymphoma and the significance of detection rearrangement of TCR γgene in diagnosis and differential diagnosis of nasal NK/T cell lymphoma. Methods Fouty-eight cases of nasal NK/T cell lymphoma were studied, immunophenotype was analyzed by immunohistochemical staining for LCA,CD79α, CD20,CD56,CD3 ,CD45RO and EBV with SP method. In situ hybridization （ISH） with EBER1/2RNA probes was perfomed. TCR γgene rearrangement was analyzed by polymerase chain reaction（PCR） technique. Results All the cases of nasal NK/T cell lymphoma were LCA positive. 44% of the cases expressed CD3 with positive signal located in the cytoplasm, which was different from peripheral T cell lymphoma. 52% and 73% and 19% of the cases were CD45RO and CD56 and EBV respectively. EBER was dedected in 81% of the cases. The positive amplification of clonal TCR γgene in 9 out of 48 samples （19%） from nasal NK/T cell lymphoma. Conclusion The immunophenotypes of nasal NK/T cell lymphoma showed less consistency. CD56 was not always positive of this tumor. The high frequency of EBER showed that these cells may have originated from NK cells. There is TCR γ gene support nasal NK-like T-cell lymphoma.