FISH analysis for EWSR1 gene rearrangement in Ewing sarcoma/PNET

目的探讨新开发的探针在福尔马林固定、石蜡包埋组织中检测染色体易位引起的EWS重排结果在Ewing肉瘤(ES)/PNET、结扎性小圆细胞瘤（DSRCT）和透明细胞肉瘤（CCS）临床诊断中的应用价值。本研究共纳入16例ES/PNETs、6例dsrct和6例CCSs。3例低分化滑膜肉瘤（SSs）、3例肺泡横纹肌肉瘤（RMSs）和3例神经母细胞瘤（NBs）作为阴性对照。使用市售的EWSR1 （22q12）双色分离重排探针对FFPE组织切片进行间期FISH分析。结果，16例ES/PNETs中有14例（87.5%）、6例DRSCTs中有6例（100%）和6例CCSs中有5例（83%）存在EWS基因重排的融合信号和橙色和绿色分裂信号，但在低分化的SSs、肺泡RMSs和NBs中未检测到。该探针对FFPE组织中EWS基因的检测具有敏感性和特异性，在ES/PNET、DSRCT和CCS的常规临床诊断中具有一定的应用价值。同样，我们研究了33个RMSs（19个胚胎RMSs，包括3个硬化型RMSs和14个叶片RMSs）。19个胚胎RMSs中有18个（94.7%）检测到荧光信号，14个胚胎RMSs中有13个（92%）检测到荧光信号。8%)肺泡RMSs。在13例肺泡型RMSs中有12例（92.3%）检测到分裂信号，但在胚胎型RMSs中没有检测到分裂信号，包括3例硬化型RMSs。胚胎RMSs和肺泡RMSs均存在扩增和多倍体。我们的FISH研究强调了商用断裂探针在检测rms上FKHR基因重排方面的优异性能。在erms和ARMSs中均检测到扩增和多倍体，因此计数细胞核信号时要小心。FISH检测在所有三种硬化型中均未发现FKHR基因重排，支持硬化性RMSs可能包括胚胎性RMSs。少

To investigate the usefulness of newly developed probes to detect EWS rearrangement results from chromosomal translocations by the FISH technique using formalin fixed, paraffin embedded tissue in the clinical diagnosis of Ewing sarcoma (ES)/PNET, desmoplastic small round cell tumor (DSRCT) and clear cell sarcoma (CCS). Sixteen ES/PNETs, 6 DSRCTs and 6 CCSs were studied in this study. Three poorly differentiated synovial sarcomas (SSs), 3 alveolar rhabdomyosarcomas (RMSs) and 3 neuroblastomas (NBs) served as negative controls. Interphase FISH analysis was performed on FFPE tissue sections with a commercially available EWSR1 (22q12) dual colour, break apart rearrangement probe. As a result, the presence of one fused signal and one split signal of orange and green, which demonstrated rearrangement of the EWS gene, was detected in 14 of 16 (87.5%) ES/PNETs, 6 of 6 (100%) DRSCTs and 5 of 6 (83%) CCSs, but was not detected in the poorly differentiated SSs, alveolar RMSs and NBs. Interphase F … More ISH using this newly developed probe is sensitive and specific for detecting the EWS gene on FFPE tissues and is of value in the routine clinical diagnosis of ES/PNET, DSRCT and CCS.Similarly, we studied 33 RMSs (19 embryonal RMSs including three of sclerosing type and 14 alveloar RMSs). The fluorescence signals were detected for 18 of 19 (94.7%) Embryonal RMSs and 13 of 14 (92. 8%) alveolar RMSs. A split signal pattern was detected in 12 of 13 (92.3%) alveolar RMSs, but in none of embryonal RMSs including three of sclerosing type. Amplification and polyploidy were found to be present in both of embryonal RMSs and alveolar RMSs. Our FISH study highlighted an excellent performance of the commercial break apart probe for detecting rearrangement of the FKHR gene on RMSs. Amplification and polyploidy were detected in both of ERMSs and ARMSs, so be careful when counting the signals of the nuclei. No rearrangement of the FKHR gene found in all three of sclerosing type by FISH assay supported sclerosing RMSs might include embryonal RMSs. Less