Among women diagnosed with stage I–IIIa, node-negative, hormone receptor (HR)-positive breast cancer (BC), Oncotype DX recurrence scores (ODX RS) inform chemotherapy treatment decisions. Differences in recurrence scores or testing may contribute to racial disparities in BC mortality among women with HR+ tumors. We identified 12,081 non-Hispanic White (NHW) and non-Hispanic Black (NHB) BC patients in Georgia (2010–2014), eligible to receive an ODX RS. Logistic regression was used to estimate the odds of chemotherapy receipt by race and ODX RS. Cox proportional hazard regression was used to calculate the hazard ratios (HRs) comparing BC mortality rates by race and recurrence score. Receipt of Oncotype testing was consistent between NHB and NHW women. Receipt of chemotherapy was generally comparable within strata of ODX RS—although NHB women with low scores were slightly more likely to receive chemotherapy (OR = 1.16, 95% CI 0.77, 1.75), and NHB women with high scores less likely to receive chemotherapy (OR = 0.77, 95% CI 0.48, 1.24), than NHW counterparts. NHB women with a low recurrence score had the largest hazard of BC mortality (HR = 2.47 95% CI 1.22, 4.99) compared to NHW women. Our data suggest that additional tumor heterogeneity, or other downstream treatment factors, not captured by ODX, may be drivers of racial disparities in HR+ BC.

在诊断为 I-IIIa 期、淋巴结阴性、激素受体 (HR) 阳性乳腺癌 (BC) 的女性中，Oncotype DX 复发评分 (ODX RS) 可为化疗治疗决策提供依据。复发评分或检测的差异可能会导致 HR+ 肿瘤女性 BC 死亡率的种族差异。我们在乔治亚州（2010-2014 年）确定了 12,081 名非西班牙裔白人 (NHW) 和非西班牙裔黑人 (NHB) BC 患者，他们有资格接受 ODX RS。Logistic 回归用于按种族和 ODX RS 估计接受化疗的几率。Cox 比例风险回归用于计算按种族和复发评分比较 BC 死亡率的风险比 (HR)。NHB 和 NHW 女性接受的 Oncotype 测试结果一致。ODX RS 各层内化疗的接受情况总体相当——尽管低分的 NHB 女性接受化疗的可能性稍高（OR = 1.16，95% CI 0.77，1.75），而高分的 NHB 女性接受化疗的可能性较小（OR = 1.16，95% CI 0.77，1.75）。 OR = 0.77, 95% CI 0.48, 1.24)，高于 NHW 同行。与 NHW 女性相比，复发评分较低的 NHB 女性 BC 死亡风险最大（HR = 2.47，95% CI 1.22，4.99）。我们的数据表明，ODX 未捕获的额外肿瘤异质性或其他下游治疗因素可能是 HR+ BC 种族差异的驱动因素。