Purpose Gene-expression profiles increasingly are used in addition to conventional prognostic factors to guide adjuvant chemotherapy (CT) decisions. The Dutch guideline suggests use of validated gene-expression profiles in patients with estrogen receptor (ER) -positive, early-stage breast cancer without overt lymph node metastases. We aimed to assess the impact of a 70-gene signature (70-GS) test on CT decisions in patients with ER-positive, early-stage breast cancer. Patients and Methods In a prospective, observational, multicenter study in patients younger than 70 years old who had undergone surgery for ER-positive, early-stage breast cancer, physicians were asked whether they intended to administer adjuvant CT before deployment of the 70-GS test and after the test result was available. Results Between October 1, 2013, and December 31, 2015, 660 patients, treated in 33 hospitals, were enrolled. Fifty-one percent of patients had pT1cN0, BRII, HER2-Neu-negative breast cancer. On the basis of conventional clinicopathological characteristics, physicians recommended CT in 270 (41%) of the 660 patients and recommended withholding CT in 107 (16%) of the 660 patients. For the remaining 43% of patients, the physicians were unsure and unable to give advice before 70-GS testing. In patients for whom CT was initially recommended or not recommended, 56% and 59%, respectively, were assigned to a low-risk profile by the 70-GS (κ, 0.02; 95% CI, -0.08 to 0.11). After disclosure of the 70-GS test result, the preliminary advice was changed in 51% of patients who received a recommendation before testing; the definitive CT recommendation of the physician was in line with the 70-GS result in 96% of patients. Conclusion In this prospective, multicenter study in a selection of patients with ER-positive, early-stage breast cancer, 70-GS use changed the physician-intended recommendation to administer CT in half of the patients.

中文翻译：

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使用 70 基因特征对雌激素受体阳性早期乳腺癌患者辅助化疗决策的影响：一项前瞻性队列研究的结果

目的 除了常规预后因素外，越来越多地使用基因表达谱来指导辅助化疗 (CT) 决策。荷兰指南建议在没有明显淋巴结转移的雌激素受体 (ER) 阳性早期乳腺癌患者中使用经过验证的基因表达谱。我们旨在评估 70 基因特征 (70-GS) 测试对 ER 阳性早期乳腺癌患者 CT 决策的影响。患者和方法 在一项针对 70 岁以下因 ER 阳性早期乳腺癌接受手术的患者的前瞻性、观察性、多中心研究中，医生被问及他们是否打算在部署 70-GS 前进行辅助 CT测试并在测试结果可用后。结果 2013 年 10 月 1 日至 2015 年 12 月 31 日期间，招募了 660 名在 33 家医院接受治疗的患者。51% 的患者患有 pT1cN0、BRII、HER2-Neu 阴性乳腺癌。根据常规临床病理特征，660 名患者中有 270 名（41%）医生推荐 CT，660 名患者中有 107 名（16%）推荐不进行 CT。对于其余 43% 的患者，医生在 70-GS 测试之前不确定并且无法提供建议。在最初推荐或不推荐 CT 的患者中，分别有 56% 和 59% 的患者被 70-GS 分配为低风险特征（κ，0.02；95% CI，-0.08 至 0.11）。在 70-GS 检测结果公布后，51% 的患者在检测前收到了建议，其中的初步建议发生了变化；医生的最终 CT 推荐与 96% 的患者的 70-GS 结果一致。结论 在这项针对 ER 阳性、早期乳腺癌患者的前瞻性、多中心研究中，70-GS 的使用改变了医生对一半患者进行 CT 的建议。