Institute of Pathology, Medizinische Hochschule Hannover, Carl Neuberg Str. 1, 30625, Hannover, Germany.
Virchows Arch. 2011 Sep;459(3):283-9. doi: 10.1007/s00428-011-1132-8. Epub 2011 Aug 2.
Interlaboratory variation in human epidermal growth factor receptor 2 (HER2) testing provides a challenge for targeted therapy in breast and gastric cancer. Assessment of positivity rates among laboratories could help monitor their performance and define reference values for positivity rates to be expected in a geographic region. Pathologists regularly determined the number of HER2-positive cases (HER2 3+, HER2 2+/amplified or amplified) in their laboratory, and figures were continuously entered into a central website. The overall positivity rate of each participant was calculated and compared with the average rates of all other institutes (n = 42). A total of 18,081 test results on breast cancer and 982 on gastric cancer were entered into the system. Positivity rates for HER2 in breast cancer ranged from 7.6% to 31.6%. Statistically, the results from six institutions qualified as outliers (p < 0.000005). From the remaining institutions encompassing 10,916 assessments, the mean proportion of positive cases was 16.7 ± 3.2% (99% confidence interval 16.6-16.8). The results from six institutions were in between the 95% and 99.5% confidence intervals. For gastric cancer, there was one outlier and the mean positivity rate was 23.2 ± 5.7%. The proportion of HER2-positive breast cancer cases is considerably lower than could have been expected from published studies. By assessing the positivity rates and comparing them with that of all breast or gastric cancers in a given population, pathologists will be alerted to a potential systematic error in their laboratory assay, causative for over- or underestimation of cancer cases suited for anti-HER2 therapy.
实验室间人表皮生长因子受体 2（HER2）检测的变异性给乳腺癌和胃癌的靶向治疗带来了挑战。评估实验室之间的阳性率有助于监测其性能，并为特定地区的阳性率设定参考值。病理学家定期确定其实验室中 HER2 阳性病例的数量（HER2 3+、HER2 2+/扩增或扩增），并将数据连续输入中央网站。计算每个参与者的总体阳性率，并与所有其他机构的平均率进行比较（n=42）。共输入了 18081 例乳腺癌和 982 例胃癌的检测结果。乳腺癌 HER2 的阳性率范围为 7.6%至 31.6%。从统计学上看，有 6 家机构的结果为离群值（p<0.000005）。在包含 10916 次评估的其余机构中，阳性病例的平均比例为 16.7±3.2%（99%置信区间 16.6-16.8）。来自 6 家机构的结果在 95%和 99.5%置信区间之间。对于胃癌，有一个离群值，阳性率平均为 23.2±5.7%。HER2 阳性乳腺癌病例的比例明显低于预期。通过评估阳性率并将其与特定人群中所有乳腺癌或胃癌的阳性率进行比较，病理学家将警惕其实验室检测中可能存在的系统误差，从而导致对适合抗 HER2 治疗的癌症病例的过度或低估。
