Department of Epidemiology and Biostatistics, University of California, San Francisco.
Department of Public Health Sciences, University of California, Davis.
JAMA Oncol. 2017 Sep 1;3(9):1228-1236. doi: 10.1001/jamaoncol.2016.6326.
Many established breast cancer risk factors are used in clinical risk prediction models, although the proportion of breast cancers explained by these factors is unknown.
To determine the population-attributable risk proportion (PARP) for breast cancer associated with clinical breast cancer risk factors among premenopausal and postmenopausal women.
DESIGN, SETTING, AND PARTICIPANTS: Case-control study with 1:10 matching on age, year of risk factor assessment, and Breast Cancer Surveillance Consortium (BCSC) registry. Risk factor data were collected prospectively from January 1, 1996, through October 31, 2012, from BCSC community-based breast imaging facilities. A total of 18 437 women with invasive breast cancer or ductal carcinoma in situ were enrolled as cases and matched to 184 309 women without breast cancer, with a total of 58 146 premenopausal and 144 600 postmenopausal women enrolled in the study.
Breast Imaging Reporting and Data System (BI-RADS) breast density (heterogeneously or extremely dense vs scattered fibroglandular densities), first-degree family history of breast cancer, body mass index (>25 vs 18.5-25), history of benign breast biopsy, and nulliparity or age at first birth (≥30 years vs <30 years).
Population-attributable risk proportion of breast cancer.
Of the 18 437 women with breast cancer, the mean (SD) age was 46.3 (3.7) years among premenopausal women and 61.7 (7.2) years among the postmenopausal women. Overall, 4747 (89.8%) premenopausal and 12 502 (95.1%) postmenopausal women with breast cancer had at least 1 breast cancer risk factor. The combined PARP of all risk factors was 52.7% (95% CI, 49.1%-56.3%) among premenopausal women and 54.7% (95% CI, 46.5%-54.7%) among postmenopausal women. Breast density was the most prevalent risk factor for both premenopausal and postmenopausal women and had the largest effect on the PARP; 39.3% (95% CI, 36.6%-42.0%) of premenopausal and 26.2% (95% CI, 24.4%-28.0%) of postmenopausal breast cancers could potentially be averted if all women with heterogeneously or extremely dense breasts shifted to scattered fibroglandular breast density. Among postmenopausal women, 22.8% (95% CI, 18.3%-27.3%) of breast cancers could potentially be averted if all overweight and obese women attained a body mass index of less than 25.
Most women with breast cancer have at least 1 breast cancer risk factor routinely documented at the time of mammography, and more than half of premenopausal and postmenopausal breast cancers are explained by these factors. These easily assessed risk factors should be incorporated into risk prediction models to stratify breast cancer risk and promote risk-based screening and targeted prevention efforts.
许多已确立的乳腺癌风险因素被用于临床风险预测模型中，尽管这些因素解释的乳腺癌比例尚不清楚。
确定绝经前和绝经后妇女中与临床乳腺癌风险因素相关的乳腺癌人群归因风险比例（PARP）。
设计、地点和参与者：这是一项病例对照研究，1:10 年龄匹配、危险因素评估年份和乳腺癌监测联合会（BCSC）登记处。从 1996 年 1 月 1 日至 2012 年 10 月 31 日，前瞻性地从 BCSC 社区乳腺成像机构收集风险因素数据。共纳入 18437 例浸润性乳腺癌或导管原位癌患者为病例，并与 184309 例无乳腺癌的患者相匹配，共纳入 58146 例绝经前和 144600 例绝经后妇女。
乳腺成像报告和数据系统（BI-RADS）乳腺密度（异质性或极密集与散在纤维腺体密度）、一级乳腺癌家族史、体重指数（>25 与 18.5-25）、良性乳腺活检史和未婚或初产年龄（≥30 岁与<30 岁）。
乳腺癌的人群归因风险比例。
在 18437 例乳腺癌患者中，绝经前妇女的平均（SD）年龄为 46.3（3.7）岁，绝经后妇女为 61.7（7.2）岁。总体而言，4747 例（89.8%）绝经前和 12502 例（95.1%）绝经后乳腺癌患者至少有 1 个乳腺癌风险因素。所有风险因素的综合 PARP 在绝经前妇女中为 52.7%（95%CI，49.1%-56.3%），在绝经后妇女中为 54.7%（95%CI，46.5%-54.7%）。乳腺密度是绝经前和绝经后妇女最常见的风险因素，对 PARP 的影响最大；如果所有乳腺密度不均匀或极密集的妇女转变为散在纤维腺体密度，39.3%（95%CI，36.6%-42.0%）的绝经前和 26.2%（95%CI，24.4%-28.0%）的绝经后乳腺癌可以得到预防。在绝经后妇女中，如果所有超重和肥胖妇女的体重指数都低于 25，22.8%（95%CI，18.3%-27.3%）的乳腺癌可以得到预防。
大多数患有乳腺癌的妇女在接受乳房 X 线摄影时至少有 1 个常规记录的乳腺癌风险因素，超过一半的绝经前和绝经后乳腺癌是由这些因素引起的。这些易于评估的风险因素应纳入风险预测模型，以分层乳腺癌风险，并促进基于风险的筛查和有针对性的预防工作。
