Symbiant Pathology Expert Centre, Alkmaar, The Netherlands.
PLoS One. 2013 Dec 4;8(12):e82018. doi: 10.1371/journal.pone.0082018. eCollection 2013.
HER-2 is a prognostic and predictive marker, but as yet no technique is perfectly able to identify patients likely to benefit from HER-2 targeted therapies. We aimed to prospectively assess the added value of first-line co-testing by IHC, and multiplex ligation-dependent probe amplification (MLPA) and chromogenic in situ hybridization (CISH).
As local validation, HER-2 MLPA and CISH were compared in 99 breast cancers. Next, we reviewed 937 invasive breast cancers, from 4 Dutch pathology laboratories, that were prospectively assessed for HER-2 by IHC and MLPA (and CISH in selected cases).
The validation study demonstrated 100% concordance between CISH and MLPA, if both methods were assessable and conclusive (81.8% of cases). Significant variation regarding percentages IHC 0/1+ and 2+ cases was observed between the laboratories (p<0.0001). Overall concordance between IHC and MLPA/CISH was 98.1% (575/586) (Kappa = 0.94). Of the IHC 3+ cases, 6.7% failed to reveal gene amplification, whereas 0.8% of the IHC 0/1+ cases demonstrated gene amplification. Results remained discordant after retrospective review in 3/11 discordant cases. In the remaining 8 cases the original IHC score was incorrect or adapted after repeated IHC staining.
MLPA is a low-cost and quantitative high-throughput technique with near perfect concordance with CISH. The use of MLPA in routinely co-testing all breast cancers may reduce HER-2 testing variation between laboratories, may serve as quality control for IHC, will reveal IHC 0/1+ patients with gene amplification, likely responsive to trastuzumab, and identify IHC 3+ cases without gene amplification that may respond less well.
HER-2 是一种预后和预测标志物，但目前尚无技术能够完美地识别出可能受益于 HER-2 靶向治疗的患者。我们旨在前瞻性评估免疫组织化学（IHC）和多重连接依赖性探针扩增（MLPA）以及显色原位杂交（CISH）一线联合检测的附加价值。
作为局部验证，我们比较了 99 例乳腺癌中 HER-2 MLPA 和 CISH 的检测结果。接下来，我们回顾了 937 例来自 4 家荷兰病理实验室的浸润性乳腺癌，这些病例前瞻性地通过 IHC 和 MLPA（并在选定病例中进行 CISH）进行了 HER-2 评估。
验证研究表明，如果两种方法均可评估且结论一致（81.8%的病例），则 CISH 与 MLPA 之间具有 100%的一致性。不同实验室之间观察到 IHC 0/1+和 2+病例的百分比存在显著差异（p<0.0001）。IHC 与 MLPA/CISH 之间的总体一致性为 98.1%（575/586）（Kappa=0.94）。IHC 3+病例中有 6.7%的病例未能显示基因扩增，而 IHC 0/1+病例中有 0.8%的病例显示基因扩增。在 3/11 例不一致病例进行回顾性复查后，结果仍然不一致。在其余 8 例中，原始的 IHC 评分不正确或在重复 IHC 染色后进行了调整。
MLPA 是一种低成本、高通量的定量技术，与 CISH 具有近乎完美的一致性。在常规联合检测所有乳腺癌中使用 MLPA 可能会减少实验室之间的 HER-2 检测差异，可作为 IHC 的质量控制手段，将显示基因扩增的 IHC 0/1+患者，可能对曲妥珠单抗有反应，并识别出可能反应较差的 IHC 3+病例而无基因扩增。
