Farias Albert J, Du Xianglin L
Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston (UTHealth), Houston, Texas.
Cancer Epidemiol Biomarkers Prev. 2017 Aug;26(8):1266-1275. doi: 10.1158/1055-9965.EPI-17-0280. Epub 2017 May 17.
There are racial disparities in breast cancer mortality. Our purpose was to determine whether racial/ethnic differences in use and discontinuation of adjuvant endocrine therapy (AET) differed by hormone receptor status and whether discontinuation was associated with mortality. We conducted a retrospective cohort study with SEER/Medicare dataset of women age ≥65 years diagnosed with stage I-III breast cancer in Medicare Part-D from 2007 to 2009, stratified by hormone receptor status. We performed multivariable logistic regressions to assess racial differences for the odds of AET initiation and Cox proportional hazards models to determine the risk of discontinuation and mortality. Of 14,902 women, 64.5% initiated AET <12 months of diagnosis. Among those with hormone receptor-positive cancer, 74.8% initiated AET compared with 5.6% of women with negative and 54.0% with unknown-receptor status. Blacks were less likely to initiate [OR, 0.76; 95% confidence interval (CI), 0.66-0.88] compared with whites. However, those with hormone receptor-positive disease were less likely to discontinue (HR, 0.89; 95% CI, 0.80-0.98). Women who initiated with aromatase inhibitors had increased risk of discontinuation compared with women who initiated tamoxifen (HR, 1.12; 95% CI, 1.05-1.20). Discontinuation within 12 months was associated with higher risk of all-cause (HR, 1.75; 95% CI, 1.74-2.00) and cancer-specific mortality (HR, 2.76; 95% CI, 1.74-4.38) after controlling for race/ethnicity. There are racial/ethnic differences in AET use and discontinuation. Discontinuing treatment was associated with higher risk of all-cause and cancer-specific mortality regardless of hormone receptor status. This study underscores the need to study factors that influence discontinuation and the survival benefits of receiving AET for hormone receptor-negative breast cancer. .
乳腺癌死亡率存在种族差异。我们的目的是确定辅助内分泌治疗（AET）的使用和停药情况在种族/族裔上的差异是否因激素受体状态而异，以及停药是否与死亡率相关。我们利用2007年至2009年医疗保险D部分中年龄≥65岁、诊断为I - III期乳腺癌的女性的SEER/医疗保险数据集进行了一项回顾性队列研究，并按激素受体状态进行分层。我们进行了多变量逻辑回归以评估AET起始几率的种族差异，并采用Cox比例风险模型来确定停药和死亡风险。在14902名女性中，64.5%在诊断后<12个月开始使用AET。在激素受体阳性癌症患者中，74.8%开始使用AET，而激素受体阴性患者为5.6%，受体状态未知的患者为54.0%。与白人相比，黑人开始使用AET的可能性较小[比值比（OR），0.76；95%置信区间（CI），0.66 - 0.88]。然而，激素受体阳性疾病患者停药的可能性较小（风险比，0.89；95% CI，0.80 - 0.98）。与开始使用他莫昔芬的女性相比，开始使用芳香化酶抑制剂的女性停药风险增加（风险比，1.12；95% CI，1.05 - 1.20）。在控制种族/族裔因素后，12个月内停药与全因死亡（风险比，1.75；95% CI，1.74 - 2.00）和癌症特异性死亡（风险比，2.76；95% CI，1.74 - 4.38）的较高风险相关。AET的使用和停药存在种族/族裔差异。无论激素受体状态如何，停药都与全因死亡和癌症特异性死亡的较高风险相关。本研究强调了研究影响停药的因素以及激素受体阴性乳腺癌接受AET的生存获益的必要性。
