Yoon Nara, Do In-Gu, Cho Eun Yoon
Department of Pathology, Samsung Medical Center, Sungkyunkwan University College of Medicine, Seoul, Korea.
APMIS. 2014 Sep;122(9):755-60. doi: 10.1111/apm.12215. Epub 2013 Dec 20.
Easy and accurate HER2 testing is essential when considering the prognostic and predictive significance of HER2 in breast cancer. The use of a fully automated, quantitative FISH assay would be helpful to detect HER2 amplification in breast cancer tissue specimens with reduced inter-laboratory variability. We compared the concordance of HER2 status as assessed by an automated FISH staining system to manual FISH testing. Using 60 formalin-fixed paraffin-embedded breast carcinoma specimens, we assessed HER2 immunoexpression with two antibodies (DAKO HercepTest and CB11). In addition, HER2 status was evaluated with automated FISH using the Leica FISH System for BOND and a manual FISH using the Abbott PathVysion DNA Probe Kit. All but one specimen were successfully stained using both FISH methods. When the data were divided into two groups according to HER2/CEP17 ratio, positive and negative, the results from both the automated and manual FISH techniques were identical for all 59 evaluable specimens. The HER2 and CEP17 copy numbers and HER2/CEP17 ratio showed great agreement between both FISH methods. The automated FISH technique was interpretable with signal intensity similar to those of the manual FISH technique. In contrast with manual FISH, the automated FISH technique showed well-preserved architecture due to low membrane digestion. HER2 immunohistochemistry and FISH results showed substantial significant agreement (κ = 1.0, p < 0.001). HER2 status can be reliably determined using a fully automated HER2 FISH system with high concordance to the well-established manual FISH method. Because of stable signal intensity and high staining quality, the automated FISH technique may be more appropriate than manual FISH for routine applications.
在考虑HER2在乳腺癌中的预后和预测意义时，简便准确的HER2检测至关重要。使用全自动定量FISH检测有助于在乳腺癌组织标本中检测HER2扩增，同时降低实验室间的变异性。我们比较了通过自动FISH染色系统评估的HER2状态与手工FISH检测结果的一致性。我们使用60份福尔马林固定石蜡包埋的乳腺癌标本，用两种抗体（DAKO HercepTest和CB11）评估HER2免疫表达。此外，使用徕卡BOND FISH系统进行自动FISH检测HER2状态，并用雅培PathVysion DNA探针试剂盒进行手工FISH检测。除一份标本外，其余所有标本均成功用两种FISH方法染色。当根据HER2/CEP17比值将数据分为阳性和阴性两组时，对于所有59份可评估标本，自动和手工FISH技术的结果均相同。两种FISH方法在HER2和CEP17拷贝数以及HER2/CEP17比值方面显示出高度一致性。自动FISH技术的信号强度与手工FISH技术相似，易于解读。与手工FISH相比，自动FISH技术由于膜消化程度低，组织结构保存良好。HER2免疫组化和FISH结果显示出高度显著一致性（κ = 1.0，p < 0.001）。使用全自动HER2 FISH系统能够可靠地确定HER2状态，与成熟的手工FISH方法具有高度一致性。由于信号强度稳定且染色质量高，自动FISH技术可能比手工FISH更适合常规应用。
