In an article published in 2016,¹ we described our method for resolving group 4 equivocal results after fluorescence in situ hybridization (FISH) testing under the 2013 ASCO/College of American Pathologists (CAP) guidelines for HER2 testing in breast cancer.² We had a total of 2,851 breast cancer tissue samples that had been submitted for human epidermal growth factor receptor 2 (HER2) testing in our reference laboratory. That study included 405 samples (14.2%) in group 4 (HER2/centromere ratio < 2 with average HER2 copy number ≥ 4.0 but < 6.0), of which 212 (7.4% of all samples tested by FISH) were ultimately reported as HER2 positive after D17S122 (Mayo Clinic, Rochester, MN) reflex FISH testing. That study also included 35 samples (1.3%) in group 2 (HER2/centromere ratio > 2 and average HER2 copy number < 4.0) and 86 samples (3%) in group 3 (HER2/centromere ratio < 2 and average HER2 copy number ≥ 6.0). The group 2 and group 3 samples were reported as being FISH positive without further reflex testing.

中文翻译：

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在参考实验室环境中（过去，现在和将来）通过荧光原位杂交测试的第4组不确定的HER2样品。

在2016年发表的一篇文章^1中，我们描述了根据2013 ASCO /美国病理学家学院（CAP）的乳腺癌原位杂交（CAP）指南进行荧光原位杂交（FISH）测试后解决第4组模棱两可结果的方法。^2个我们总共有2,851份乳腺癌组织样品已提交给我们的参考实验室进行人表皮生长因子受体2（HER2）测试。该研究包括第4组的405个样本（14.2％）（HER2 /着丝粒比率<2，平均HER2拷贝数≥4.0但<6.0），其中212个（FISH检测的所有样本的7.4％）最终被报告为HER2阳性在D17S122（明尼苏达州罗彻斯特市梅奥诊所）进行反射性FISH测试后。该研究还包括第2组（HER2 /着丝粒比率> 2和平均HER2拷贝数<4.0）中的35个样本（1.3％）和第3组（HER2 /着丝粒比率<2和平均HER2拷贝数）的86个样本（3％） ≥6.0）。据报道，第2组和第3组样品未经进一步反射测试即为FISH阳性。