摘要目的:探讨SS18-SSX融合特异性抗体和C-末端SSX抗体在滑膜肉瘤中的表达情况及诊断价值。方法:收集东部战区总医院病理科2013年8月至2020年12月诊断的51例经分子检测证实的滑膜肉瘤和94例其他类型的软组织肿瘤，采用免疫组织化学EnVision法检测SS18-SSX和C-末端SSX的表达情况。结果:51例滑膜肉瘤中，48例（48/51）显示SS18-SSX强和弥漫的细胞核表达，阳性率为94.1%；而在94例非滑膜肉瘤肿瘤中均为阴性。C-末端SSX在所有滑膜肉瘤（51/51）中均为强和弥漫的细胞核表达，阳性率为100%；而在94例非滑膜肉瘤肿瘤中有6例（6/94，6.4%）也存在不同程度的表达，包括2例平滑肌肉瘤、2例纤维肉瘤、1例恶性外周神经鞘膜瘤和1例胚胎性横纹肌肉瘤。SS18-SSX诊断滑膜肉瘤的灵敏度和特异度分别为94.1%和100%；而C-末端SSX的灵敏度和特异度分别为100%和93.6%。结论:SS18-SSX融合特异性抗体和C-末端SSX抗体均为诊断滑膜肉瘤高度灵敏和特异的标志物，可以替代荧光原位杂交技术或其他分子病理检测用于绝大多数滑膜肉瘤的诊断。

abstractsObjective:To investigate the expression and diagnostic value of SS18-SSX fusion-specific antibody and SSX C-terminal antibody in synovial sarcoma (SS).Methods:Immunohistochemical (IHC) EnVision method was used to detect the expression of SS18-SSX fusion-specific antibody and SSX C-terminal antibody in 51 genetically confirmed cases of SS and 94 non-SS tumors diagnosed at Nanjing Jinling Hospital from August 2013 to December 2020.Results:IHC staining for SS18-SSX fusion-specific antibody revealed strongly diffuse nuclear staining in 48 of 51 (48/51, 94.1%) SS cases, whereas none of the 94 non-SS tumors showed any staining. IHC staining for SSX C-terminal antibody showed strongly diffuse nuclear staining in all 51 (51/51, 100%) SS cases; six of the 94 (6/94, 6.4%) non-SS tumors showed variable staining, including two cases each of leiomyosarcoma and fibrosarcoma, and one case each of malignant peripheral nerve sheath tumor and embryonal rhabdomyosarcoma. The sensitivity and specificity of SS18-SSX fusion-specific antibody in diagnosing SS were 94.1% and 100% and these of SSX C-terminal antibody were 100% and 93.6%, respectively.Conclusions:SS18-SSX fusion-specific antibody and SSX C-terminal antibody are highly sensitive and specific markers for SS. Immunohistochemistry using these antibodies may replace FISH or molecular genetic testing in most cases.