Peng Rongxue, Zhang Kuo, Lin Guigao, Li Jinming
National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology, No.1 Da Hua Road, Dongdan, Beijing, 100730, People's Republic of China.
Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, P R China.
Diagn Pathol. 2024 Dec 20;19(1):161. doi: 10.1186/s13000-024-01588-w.
Accurate detection of human epidermal growth factor receptor 2 (HER2) gene amplification via fluorescence in situ hybridization (FISH) is necessary to determine HER2 status. Although many attempts have been made to increase the consistency of the results, the actual situation still needs to be determined. To investigate the latest interlaboratory variability of HER2 FISH testing for breast cancer, a multicenter proficiency-testing ring study was conducted in China.
A total of ten samples, each exhibiting distinct HER2 signal patterns and genetic heterogeneity, were distributed to 169 laboratories for HER2 FISH analysis. Data comprising both the results of the tests and feedback from questionnaires were compiled for comprehensive evaluation.
The overall agreement among the participating laboratories was substantial to almost perfect, with a Fleiss' kappa value of 0.765-0.911. However, it is important to note that cases with characteristics of HER2 signals near the critical cutoff range or with genetic heterogeneity showed lower congruence, poorer reproducibility, and higher variability (Fleiss' kappa: 0.582). Our questionnaire showed that 52.2% (86/168) of the participants did not perform validation after their operation procedures or interpretation criteria were updated, and 75.6% (121/160) of the participants did not establish standard interpretation procedures. Since these laboratories showed worse performance (P < 0.05), the lack of validation and interpretation procedures was speculated to be the possible underlying cause.
This study presents the latest landscape of interlaboratory variability and accuracy of HER2 FISH testing in China and highlights potential causes for the variability. Despite many years of effort, the standardization of HER2 status determination still has a long way to go.
通过荧光原位杂交（FISH）准确检测人表皮生长因子受体2（HER2）基因扩增对于确定HER2状态至关重要。尽管已进行了许多尝试以提高结果的一致性，但实际情况仍有待确定。为了调查中国乳腺癌HER2 FISH检测的最新实验室间变异性，开展了一项多中心能力验证循环研究。
总共十个样本，每个样本都呈现出不同的HER2信号模式和基因异质性，被分发给169个实验室进行HER2 FISH分析。收集包括测试结果和问卷反馈在内的数据进行综合评估。
参与实验室之间的总体一致性很高，几乎达到完美，Fleiss卡方值为0.765 - 0.911。然而，需要注意的是，HER2信号特征接近临界截断范围或具有基因异质性的病例一致性较低、重现性较差且变异性较高（Fleiss卡方：0.582）。我们的问卷显示，52.2%（86/168）的参与者在操作程序或解释标准更新后未进行验证，75.6%（121/160）的参与者未建立标准解释程序。由于这些实验室表现较差（P < 0.05），推测缺乏验证和解释程序可能是潜在原因。
本研究展示了中国HER2 FISH检测的实验室间变异性和准确性的最新情况，并突出了变异性的潜在原因。尽管经过多年努力，HER2状态测定的标准化仍有很长的路要走。
