From the Department of Pathology (Shet, Tambe, Phadatare, Panjwani, Desai), National Cancer Grid (Sengar, Pramesh), Tata Memorial Hospital, Mumbai, India.
Arch Pathol Lab Med. 2024 Sep 1;148(9):1028-1034. doi: 10.5858/arpa.2023-0260-OA.
CONTEXT.—: Biomarkers in breast cancer need strict monitoring given their role in patient management.
OBJECTIVE.—: To study the impact that regular participation in the National Cancer Grid (NCG) external quality assurance (EQA) system has on concordance rates for biomarkers in breast carcinoma.
DESIGN.—: Tissue microarrays (TMAs) containing breast carcinomas were circulated to participating laboratories that performed immunohistochemistry for breast biomarkers. The returned TMAs were then assessed for test concordance.
RESULTS.—: A total of 105 laboratories participated in the estrogen receptor (ER) and progesterone receptor (PR) EQA system cycles, and 99 centers participated in the human epidermal growth factor 2 (HER2) EQA system. In the ER EQA in the first cycle only 1 laboratory had a 100% concordance rate, which improved to 59 of 77 (76.6%) and 85 of 97 (87.6%) in the fourth and fifth cycles, respectively. In the PR EQA the 100% pass rate jumped from zero to 52 of 76 (68.4%) in the fourth cycle and 86 of 97 (88.6%) in the last cycle. For HER2 EQA, the 100% pass rates were seen in 7 of 23 laboratories (30.4%) in the first cycle, 49 of 78 laboratories (62.8%) in the fourth cycle, and 48 of 94 laboratories (51.1%) in fifth cycle of EQA. Centers that participated in the NCG EQA system for a longer period often changed testing methodology, with consequent improvement in their laboratory concordance rates. An increasing trend for the use of automated platforms and of the US Food and Drug Administration-approved antibody for HER2 testing was observed.
CONCLUSIONS.—: Our experience demonstrates that laboratory performance improves with participation in an EQA system even in less perfect settings, and this drives the placement of more proficient practices across the country.
生物标志物在乳腺癌患者管理中具有重要作用，需要对其进行严格监测。
研究定期参加国家癌症网格（NCG）外部质量保证（EQA）系统对乳腺癌中生物标志物一致性率的影响。
将包含乳腺癌的组织微阵列（TMA）分发给进行乳腺癌生物标志物免疫组织化学检测的参与实验室。然后评估返回的 TMA 以评估测试一致性。
共有 105 个实验室参加了雌激素受体（ER）和孕激素受体（PR）EQA 系统循环，99 个中心参加了人表皮生长因子 2（HER2）EQA 系统。在第一个 ER EQA 循环中，只有 1 个实验室的一致性率达到 100%，在第四个和第五个循环中分别提高到 77 个中的 59 个（76.6%）和 97 个中的 85 个（87.6%）。在 PR EQA 中，100%通过率从 0 跃升至第四个循环中的 76 个中的 52 个（68.4%）和最后一个循环中的 97 个中的 86 个（88.6%）。在 HER2 EQA 中，在第一个循环中有 23 个实验室中的 7 个（30.4%），在第四个循环中有 78 个实验室中的 49 个（62.8%）和第五个循环中有 94 个实验室中的 48 个（51.1%）达到 100%通过率。参与 NCG EQA 系统时间较长的中心通常会改变测试方法，从而提高实验室的一致性率。观察到用于 HER2 检测的自动化平台和美国食品和药物管理局批准的抗体的使用呈上升趋势。
我们的经验表明，即使在不太完善的环境中，实验室的性能也会随着参与 EQA 系统而提高，这推动了全国更熟练实践的普及。
