All authors: Sunnybrook Health Sciences Centre, University of Toronto Faculty of Medicine, Toronto, Ontario, Canada.
J Clin Oncol. 2017 Sep 10;35(26):3039-3045. doi: 10.1200/JCO.2016.70.5319. Epub 2017 Apr 26.
Purpose To study the effect of the 2013 updates to the 2007 American Society of Clinical Oncology/College of American Pathologists recommendations for human epidermal growth factor receptor 2 (HER2) testing in breast cancer on testing patterns and interpretation in a large regional reference laboratory. Patients and Methods Patient cases with HER2 testing scores for breast biomarker evaluation were selected from our laboratory information system during two 12-month periods (2012 and 2014). The number of tests performed, type of specimens, proportion of HER2-positive and equivocal patient cases, and number of repeat tests on subsequent excisional specimens were examined and compared. Results Although the number of samples tested increased between 2012 and 2014 (2,201 v 2,558 patient cases; 2,278 v 2,659 tumors), HER2 positivity remained constant (15.7% v 15.5%, respectively). The number of repeat tests performed within 6 months more than doubled (122 [5.5%) of 2,201 v 302 [11.8%] of 2,558; P < .001), and the proportion of immunohistochemistry (IHC) 2+ tumors was significantly lower in 2014 than in 2012 (20.3% v 25.3%; P < .001). However, the proportion of patient cases with unresolved HER2 statuses (equivocal by IHC and in situ hybridization) was significantly higher in 2014 (four of 2,278 v 90 of 2,660; P < .001). Conclusion Our findings indicate that the 2013 updates to the American Society of Clinical Oncology/College of American Pathologists recommendations for HER2 testing in breast cancer did not affect the overall HER2-positivity rate or the proportion of patients eligible for HER2-targeted therapy. The proportion of tests and repeat tests performed increased, as did the number of patient cases categorized as ISH equivocal. The benefit of targeted therapy in the equivocal group is not proven, so targeted therapy should not be considered for patients in this category which should be redefined in future iterations of the recommendations.
研究 2013 年美国临床肿瘤学会/美国病理学家协会（ASCO/CAP）对人表皮生长因子受体 2（HER2）检测的 2007 年推荐更新对大型区域参考实验室中 HER2 检测模式和解释的影响。
从我们的实验室信息系统中选择两个 12 个月（2012 年和 2014 年）的患者病例，这些病例的 HER2 检测结果用于评估乳腺癌生物标志物。检查并比较了测试数量、标本类型、HER2 阳性和不确定患者病例的比例以及后续切除标本的重复测试数量。
尽管 2012 年至 2014 年测试的样本数量有所增加（2201 例患者病例与 2558 例患者病例；2278 例肿瘤与 2659 例肿瘤），但 HER2 阳性率保持不变（分别为 15.7%和 15.5%）。在 6 个月内进行的重复测试数量增加了一倍以上（2201 例中的 122 例[5.5%]与 2558 例中的 302 例[11.8%]；P<.001），并且 2014 年的免疫组织化学（IHC）2+肿瘤比例明显低于 2012 年（20.3%与 25.3%；P<.001）。然而，2014 年 HER2 状态不确定的患者病例比例明显更高（2278 例中有 4 例与 2660 例中有 90 例；P<.001）。
我们的研究结果表明，2013 年对 ASCO/CAP 乳腺癌 HER2 检测建议的更新并未影响总体 HER2 阳性率或符合 HER2 靶向治疗条件的患者比例。进行的测试和重复测试的比例增加，IHC 不确定和原位杂交（ISH）不确定的患者病例比例也增加。不确定组的靶向治疗获益尚未得到证实，因此不应考虑对该类患者进行靶向治疗，应在未来的建议迭代中对其进行重新定义。
