PDF(Pubmed)
Abstract：
BACKGROUND: Associations between reproductive factors and risk of breast cancer differ by subtype defined by joint estrogen receptor (ER), progesterone receptor (PR), and HER2 expression status. Racial and ethnic differences in the incidence of breast cancer subtypes suggest etiologic heterogeneity, yet data are limited because most studies have included non-Hispanic White women only.
METHODS: We analyzed harmonized data for 2,794 breast cancer cases and 4,579 controls, of whom 90% self-identified as African American, Asian American or Hispanic. Questionnaire data were pooled from three population-based studies conducted in California and data on tumor characteristics were obtained from the California Cancer Registry. The study sample included 1,530 luminal A (ER-positive and/or PR-positive, HER2-negative), 442 luminal B (ER-positive and/or PR-positive, HER2-positive), 578 triple-negative (TN; ER-negative, PR-negative, HER2-negative), and 244 HER2-enriched (ER-negative, PR-negative, HER2-positive) cases. We used multivariable unconditional logistic regression models to estimate subtype-specific ORs and 95% confidence intervals associated with parity, breast-feeding, and other reproductive characteristics by menopausal status and race and ethnicity.
RESULTS: Subtype-specific associations with reproductive factors revealed some notable differences by menopausal status and race and ethnicity. Specifically, higher parity without breast-feeding was associated with higher risk of luminal A and TN subtypes among premenopausal African American women. In contrast, among Asian American and Hispanic women, regardless of menopausal status, higher parity with a breast-feeding history was associated with lower risk of luminal A subtype. Among premenopausal women only, luminal A subtype was associated with older age at first full-term pregnancy (FTP), longer interval between menarche and first FTP, and shorter interval since last FTP, with similar OR estimates across the three racial and ethnic groups.
CONCLUSIONS: Subtype-specific associations with reproductive factors overall and by menopausal status, and race and ethnicity, showed some differences, underscoring that understanding etiologic heterogeneity in racially and ethnically diverse study samples is essential. Breast-feeding is likely the only reproductive factor that is potentially modifiable. Targeted efforts to promote and facilitate breast-feeding could help mitigate the adverse effects of higher parity among premenopausal African American women.
METHODS: We analyzed harmonized data for 2,794 breast cancer cases and 4,579 controls, of whom 90% self-identified as African American, Asian American or Hispanic. Questionnaire data were pooled from three population-based studies conducted in California and data on tumor characteristics were obtained from the California Cancer Registry. The study sample included 1,530 luminal A (ER-positive and/or PR-positive, HER2-negative), 442 luminal B (ER-positive and/or PR-positive, HER2-positive), 578 triple-negative (TN; ER-negative, PR-negative, HER2-negative), and 244 HER2-enriched (ER-negative, PR-negative, HER2-positive) cases. We used multivariable unconditional logistic regression models to estimate subtype-specific ORs and 95% confidence intervals associated with parity, breast-feeding, and other reproductive characteristics by menopausal status and race and ethnicity.
RESULTS: Subtype-specific associations with reproductive factors revealed some notable differences by menopausal status and race and ethnicity. Specifically, higher parity without breast-feeding was associated with higher risk of luminal A and TN subtypes among premenopausal African American women. In contrast, among Asian American and Hispanic women, regardless of menopausal status, higher parity with a breast-feeding history was associated with lower risk of luminal A subtype. Among premenopausal women only, luminal A subtype was associated with older age at first full-term pregnancy (FTP), longer interval between menarche and first FTP, and shorter interval since last FTP, with similar OR estimates across the three racial and ethnic groups.
CONCLUSIONS: Subtype-specific associations with reproductive factors overall and by menopausal status, and race and ethnicity, showed some differences, underscoring that understanding etiologic heterogeneity in racially and ethnically diverse study samples is essential. Breast-feeding is likely the only reproductive factor that is potentially modifiable. Targeted efforts to promote and facilitate breast-feeding could help mitigate the adverse effects of higher parity among premenopausal African American women.
摘要：
背景：生殖因素与乳腺癌风险之间的关联因联合雌激素受体（ER）定义的亚型而异，孕激素受体（PR），和HER2表达状态。乳腺癌亚型发病率的种族和种族差异提示病因异质性，但数据有限,因为大多数研究仅包括非西班牙裔白人女性.
方法：我们分析了2,794例乳腺癌病例和4,579例对照的协调数据，其中90%的人自称是非洲裔美国人，亚裔美国人或西班牙裔。问卷数据来自在加利福尼亚进行的三项基于人群的研究，肿瘤特征的数据来自加利福尼亚癌症登记处。研究样本包括1,530个管腔A（ER阳性和/或PR阳性，HER2阴性)，442腔B（ER阳性和/或PR阳性，HER2阳性），578三负(TN；ER阴性，PR-阴性,HER2阴性)，和244HER2富集（ER阴性，PR-阴性,HER2阳性）病例。我们使用多变量非条件逻辑回归模型来估计亚型特异性OR和与奇偶校验相关的95%置信区间。母乳喂养,和其他生殖特征取决于更年期状况和种族和民族。
结果：与生殖因素的亚型特异性关联显示出更年期状态和种族和民族之间存在一些显着差异。具体来说,在绝经前非裔美国女性中,无母乳喂养的产次较高与腔A和TN亚型的风险较高相关.相比之下,在亚裔美国人和西班牙裔女性中，无论更年期状态如何，具有母乳喂养史的更高的平差与腔A型亚型的风险较低相关.仅在绝经前女性中，管腔A亚型与首次足月妊娠（FTP）时年龄较大有关，月经初潮和第一次FTP之间的间隔较长，和自上次FTP以来的较短间隔，在三个种族和族裔群体中，OR估计相似。
结论：亚型特异性关联与生殖因素总体和绝经状态，种族和民族，显示出一些差异，强调了解种族和种族多样性研究样本的病因异质性至关重要.母乳喂养可能是唯一可能改变的生殖因素。促进和促进母乳喂养的有针对性的努力可以帮助减轻绝经前非裔美国妇女中更高的均等的不利影响。
方法：我们分析了2,794例乳腺癌病例和4,579例对照的协调数据，其中90%的人自称是非洲裔美国人，亚裔美国人或西班牙裔。问卷数据来自在加利福尼亚进行的三项基于人群的研究，肿瘤特征的数据来自加利福尼亚癌症登记处。研究样本包括1,530个管腔A（ER阳性和/或PR阳性，HER2阴性)，442腔B（ER阳性和/或PR阳性，HER2阳性），578三负(TN；ER阴性，PR-阴性,HER2阴性)，和244HER2富集（ER阴性，PR-阴性,HER2阳性）病例。我们使用多变量非条件逻辑回归模型来估计亚型特异性OR和与奇偶校验相关的95%置信区间。母乳喂养,和其他生殖特征取决于更年期状况和种族和民族。
结果：与生殖因素的亚型特异性关联显示出更年期状态和种族和民族之间存在一些显着差异。具体来说,在绝经前非裔美国女性中,无母乳喂养的产次较高与腔A和TN亚型的风险较高相关.相比之下,在亚裔美国人和西班牙裔女性中，无论更年期状态如何，具有母乳喂养史的更高的平差与腔A型亚型的风险较低相关.仅在绝经前女性中，管腔A亚型与首次足月妊娠（FTP）时年龄较大有关，月经初潮和第一次FTP之间的间隔较长，和自上次FTP以来的较短间隔，在三个种族和族裔群体中，OR估计相似。
结论：亚型特异性关联与生殖因素总体和绝经状态，种族和民族，显示出一些差异，强调了解种族和种族多样性研究样本的病因异质性至关重要.母乳喂养可能是唯一可能改变的生殖因素。促进和促进母乳喂养的有针对性的努力可以帮助减轻绝经前非裔美国妇女中更高的均等的不利影响。
