IHC与FISH检测浸润性乳腺癌患者HER2蛋白表达和基因扩增的差异性分析

目的:探讨并比较免疫组织化学法（IHC）与荧光原位杂交法（FISH）检测浸润性乳腺癌人表皮生长因子受体-2（HER2）蛋白表达和基因扩增的差异性。方法:采用IHC法和FISH法分别检测桂西地区120例乳腺癌患者石蜡标本中HER2蛋白表达与基因扩增情况，比较IHC与FISH检测结果一致性并进行结果相关性分析。对检测不一致的病例重新检测及判读，分析差异原因。结果:120例乳腺癌患者中IHC 33例阳性（3+）中FISH检测阳性33例，阳性符合率100%；IHC 61例不确定（2+）中FISH检测阳性24例，阳性符合率39.34%；IHC 26例阴性（0/1+）中FISH检测阴性21例，阴性符合率80.77%。结果显示，除IHC（2+）外，IHC检测HER2蛋白表达与FISH检测HER2基因扩增有较好的一致性（P＜0.05）。造成两种检测方法差异的原因可能有标本固定不及时，抗体浓度偏低等。结论:IHC法检测HER2与FISH法一致性较好。临床实践中可根据实际情况，结合使用，以便指导临床治疗。

Difference and correlation between IHC and FISH in detecting HER2 protein expression and gene amplification in invasive breast cancer

Objective:To investigate the difference and correlation between immunohistochemistry(IHC)and fluorescence in situ hybridization(FISH)in detecting human epidermal growth factor receptor-2(HER2)protein expression and gene amplification in invasive breast cancer.Methods:HER2 protein expression and gene amplification in 120 breast cancer patients in western area of Guangxi were detected by IHC method and FISH method respectively.The consistency of IHC and FISH test results was compared and the correlation analysis was conducted.The cases with inconsistent test were re-tested and interpreted,and the reasons for the difference were analyzed.Results:Among the 120 breast cancer patients,in 33 cases with positive IHC(3+),33 cases had positive FISH test,with the positive coincidence rate of 100%.Among the 61 cases with IHC equivocal(2+),24 were positive for FISH test,with the positive coincidence rate of 39.34%.The results showed that in addition to IHC(2+),the HER2 protein expression detected by IHC was consistent with the HER2 gene amplification detected by FISH.Among the 26 were negative for IHC(0/1+)and 21 were negative for FISH test,with the negative coincidence rate of 80.77%(P<0.05).The reasons for the difference between the two detection methods included samples was not fixed in time,low concentration of primary antibody and updated guidelines.Conclusion:The consistency between IHC and FISH method was better.In clinical practice,genetic testing methods can be selected according to the actual situation,to guiding clinical treatment.