Sahlgrenska Breast Center, Department of Surgery, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden.
Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
BMC Cancer. 2021 Apr 21;21(1):439. doi: 10.1186/s12885-021-08171-2.
Routine clinical management of breast cancer (BC) currently depends on surrogate subtypes according to estrogen- (ER) and progesterone (PR) receptor, Ki-67, and HER2-status. However, there has been growing demand for reduced immunohistochemistry (IHC) turnaround times. The Xpert® Breast Cancer STRAT4* Assay (STRAT4)*, a standardized test for ESR1/PGR/MKi67/ERBB2 mRNA biomarker assessment, takes less than 2 hours. Here, we compared the concordance between the STRAT4 and IHC/SISH, thereby evaluating the effect of method choice on surrogate subtype assessment and adjuvant treatment decisions.
In total, 100 formalin-fixed paraffin-embedded core needle biopsy (CNB) samples and matching surgical specimens for 98 patients with primary invasive BC were evaluated using the STRAT4 assay. The concordance between STRAT4 and IHC was calculated for individual markers for the CNB and surgical specimens. In addition, we investigated whether changes in surrogate BC subtyping based on the STRAT4 results would change adjuvant treatment recommendations.
The overall percent agreement (OPA) between STRAT4 and IHC/SISH ranged between 76 and 99% for the different biomarkers. Concordance for all four biomarkers in the surgical specimens and CNBs was only 66 and 57%, respectively. In total, 74% of surgical specimens were concordant for subtype, regardless of the method used. IHC- and STRAT4-based subtyping for the surgical specimen were shown to be discordant for 25/98 patients and 18/25 patients would theoretically have been recommended a different adjuvant treatment, primarily receiving more chemotherapy and trastuzumab.
A comparison of data from IHC/in situ hybridization and STRAT4 demonstrated that subsequent changes in surrogate subtyping for the surgical specimen may theoretically result in more adjuvant treatment given, primarily with chemotherapy and trastuzumab.
目前，乳腺癌（BC）的常规临床管理依赖于根据雌激素受体（ER）和孕激素受体（PR）、Ki-67 和 HER2 状态的替代亚型。然而，人们对减少免疫组织化学（IHC）周转时间的需求不断增加。Xpert®乳腺癌 STRAT4* 检测（STRAT4*）是一种用于评估 ESR1/PGR/MKi67/ERBB2 mRNA 生物标志物的标准化检测，耗时不到 2 小时。在这里，我们比较了 STRAT4 与 IHC/SISH 的一致性，从而评估了方法选择对替代亚型评估和辅助治疗决策的影响。
总共评估了 98 例原发性浸润性 BC 患者的 100 例福尔马林固定石蜡包埋核心针活检（CNB）样本和匹配的手术标本，使用 STRAT4 检测。计算了 CNB 和手术标本中单个标志物的 STRAT4 和 IHC 的一致性。此外，我们还研究了基于 STRAT4 结果的替代 BC 亚型分类的变化是否会改变辅助治疗建议。
STRAT4 与 IHC/SISH 的总百分比一致性（OPA）在不同的生物标志物之间在 76%至 99%之间。手术标本和 CNB 中所有四个生物标志物的一致性分别为 66%和 57%。无论使用何种方法，手术标本中共有 74%的亚型是一致的。基于 IHC 和 STRAT4 的手术标本的亚分型显示为 25/98 例患者不一致，18/25 例患者理论上会被推荐不同的辅助治疗，主要是接受更多的化疗和曲妥珠单抗。
IHC/原位杂交和 STRAT4 数据的比较表明，手术标本替代亚型的后续变化可能会导致更多的辅助治疗，主要是化疗和曲妥珠单抗。
