Division of Hematology and Oncology, University of Illinois at Chicago, Chicago.
Translational Oncology Program, University of Illinois Cancer Center, Chicago.
JAMA Oncol. 2021 Mar 1;7(3):370-378. doi: 10.1001/jamaoncol.2020.7320.
Given the widespread use of the 21-gene recurrence score for identifying candidates for adjuvant chemotherapy, it is important to examine the performance of the Oncotype DX Breast Recurrence Score test in diverse patient populations to validate this approach for tailoring treatment in women in racial/ethnic minority groups.
To examine whether breast cancer-specific mortality for women with hormone-dependent breast cancer differs by race/ethnicity across risk categories defined by the Oncotype DX Breast Recurrence Score test and whether the prognostic accuracy of the 21-gene recurrence score differs by race/ethnicity.
DESIGN, SETTING, AND PARTICIPANTS: This retrospective, population-based cohort study used the Surveillance, Epidemiology, and End Results Oncotype DX 2004-2015 database to obtain breast cancer-specific survival data on US women 18 years and older who were diagnosed with first primary stage I to III, estrogen receptor-positive breast cancer between January 1, 2004, and December 31, 2015, and had tumor testing through the Genomic Health Clinical Laboratory. Data were analyzed from April 20 to September 27, 2020.
The primary outcome was breast cancer-specific mortality among women from different racial/ethnic groups stratified by the 21-gene recurrence score risk categories. Secondary analyses compared the prognostic accuracy of the recurrence score among the different racial/ethnic groups.
A total of 86 033 patients with breast cancer (mean [SD] age, 57.6 [10.6] years) with Oncotype DX Breast Recurrence Score test information were available for the analysis, including 64 069 non-Hispanic White women (74.4%), 6719 non-Hispanic Black women (7.8%), 7944 Hispanic women (9.2%), 6950 Asian/Pacific Islander women (8.0%), and 351 American Indian/Alaska Native women (0.4%). Black women were significantly more likely than non-Hispanic White women to have a recurrence score greater than 25 (17.7% vs 13.7%; P < .001). Among women with axillary node-negative tumors, competing risk models adjusted for age, tumor characteristics, and treatment found higher breast cancer-specific mortality for Black compared with non-Hispanic White women within each recurrence score risk stratum, with subdistribution hazard ratios of 2.54 (95% CI, 1.44-4.50) for Black women with recurrence scores of 0 to 10, 1.64 (95% CI, 1.23-2.18) for Black women with recurrence scores of 11 to 25, and 1.48 (95% CI, 1.10-1.98) for Black women with scores greater than 25. The prognostic accuracy of the recurrence score was significantly lower for Black women, with a C index of 0.656 (95% CI, 0.592-0.720) compared with 0.700 (95% CI, 0.677-0.722) (P = .002) for non-Hispanic Whites.
In this cohort study, Black women in the US were more likely to have a high-risk recurrence score and to die of axillary node-negative breast cancer compared with non-Hispanic White women with comparable recurrence scores. The Oncotype DX Breast Recurrence Score test has lower prognostic accuracy in Black women, suggesting that genomic assays used to identify candidates for adjuvant chemotherapy may require model calibration in populations with greater racial/ethnic diversity.
重要性：鉴于广泛使用 21 基因复发评分来识别辅助化疗的候选者，因此，有必要在不同的患者人群中检验 Oncotype DX 乳腺复发评分检测的性能，以验证这种针对少数民族群体中女性的治疗方法。
目的：检测激素依赖性乳腺癌患者的乳腺癌特异性死亡率是否因种族/民族而在 Oncotype DX 乳腺复发评分定义的风险类别中存在差异，以及 21 基因复发评分的预后准确性是否因种族/民族而存在差异。
设计、地点和参与者：本回顾性、基于人群的队列研究使用监测、流行病学和最终结果 Oncotype DX 2004-2015 数据库，获取 2004 年 1 月 1 日至 2015 年 12 月 31 日期间美国年龄在 18 岁及以上、被诊断为 I 期至 III 期、雌激素受体阳性乳腺癌且肿瘤经基因组健康临床实验室检测的女性的乳腺癌特异性生存数据。数据于 2020 年 4 月 20 日至 9 月 27 日进行分析。
主要结局和测量：主要结局是根据 21 基因复发评分风险类别，不同种族/民族组女性的乳腺癌特异性死亡率。次要分析比较了不同种族/民族组复发评分的预后准确性。
结果：共分析了 86033 名接受过 Oncotype DX 乳腺复发评分检测的乳腺癌患者（平均[标准差]年龄为 57.6[10.6]岁），其中包括 64069 名非西班牙裔白人女性（74.4%）、6719 名非西班牙裔黑人女性（7.8%）、7944 名西班牙裔女性（9.2%）、6950 名亚裔/太平洋岛民女性（8.0%）和 351 名美洲印第安人/阿拉斯加原住民女性（0.4%）。黑人女性的复发评分大于 25 的比例明显高于非西班牙裔白人女性（17.7%比 13.7%；P < .001）。在腋窝淋巴结阴性肿瘤的女性中，经年龄、肿瘤特征和治疗调整的竞争风险模型发现，黑人女性的乳腺癌特异性死亡率在每个复发评分风险分层内均高于非西班牙裔白人女性，其亚分布风险比为 2.54（95%CI，1.44-4.50），复发评分 0 至 10 的黑人女性、11 至 25 的黑人女性和评分大于 25 的黑人女性分别为 1.64（95%CI，1.23-2.18）和 1.48（95%CI，1.10-1.98）。黑人女性的复发评分预后准确性显著降低，黑人女性的 C 指数为 0.656（95%CI，0.592-0.720），而非西班牙裔白人女性为 0.700（95%CI，0.677-0.722）（P = .002）。
结论和相关性：在这项队列研究中，美国黑人女性与具有可比复发评分的非西班牙裔白人女性相比，更有可能具有高风险的复发评分和死于腋窝淋巴结阴性乳腺癌。Oncotype DX 乳腺复发评分检测在黑人女性中的预后准确性较低，这表明用于确定辅助化疗候选者的基因组检测可能需要在种族/民族多样性更大的人群中进行模型校准。
