Stålhammar Gustav, Rosin Gustaf, Fredriksson Irma, Bergh Jonas, Hartman Johan
Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden; Department of Clinical Pathology, Karolinska University Hospital, Stockholm, Sweden.
Histopathology. 2014 Jun;64(7):971-80. doi: 10.1111/his.12344. Epub 2014 Feb 5.
The aim of this study was to investigate in primary breast cancer the congruency of routine clinical predictive biomarker evaluations, including ER, PR and Ki67, obtained using immunocytochemistry (ICC) and immunohistochemistry (IHC).
Clinicopathological data were collected on all women diagnosed with primary breast cancer at Karolinska University Hospital in 2011. A total of 346 patients were included in a retrospective paired comparison of predictive biomarker evaluations on direct smear ICC and IHC. This showed a low congruency between findings with the two methods, especially evident for Ki67 (κ = 0.35-0.42). By suggested adjustments to ICC cut-offs, we managed to improve the inter-rater agreement of Ki67 classification slightly to κ = 0.46.
Our findings suggest that routine clinical ICC and IHC evaluations of predictive biomarkers produce discordant results. Consequently, basing therapeutic decisions on cytology with cut-offs defined for IHC induces a risk that patients will receive suboptimal therapy. However, our analysis shows that local adjustments to biomarker cut-off levels may improve congruency and increase the probability of correct classifications.
本研究旨在调查原发性乳腺癌中，使用免疫细胞化学（ICC）和免疫组织化学（IHC）获得的常规临床预测生物标志物评估（包括雌激素受体、孕激素受体和Ki67）的一致性。
收集了2011年在卡罗林斯卡大学医院被诊断为原发性乳腺癌的所有女性的临床病理数据。对346例患者进行了直接涂片ICC和IHC预测生物标志物评估的回顾性配对比较。结果显示，两种方法的结果一致性较低，尤其是Ki67（κ=0.35-0.42）。通过对ICC临界值的建议调整，我们设法将Ki67分类的评分者间一致性略微提高到κ=0.46。
我们的研究结果表明，预测生物标志物的常规临床ICC和IHC评估会产生不一致的结果。因此，基于为IHC定义的临界值进行细胞学治疗决策，会使患者接受次优治疗的风险增加。然而，我们的分析表明，对生物标志物临界值水平进行局部调整可能会提高一致性，并增加正确分类的概率。
