Combined hormone replacement therapy use in relation to breast cancer mortality.

描述(由申请人提供)：项目摘要越来越明显地表明，正在接受联合激素替代疗法(CHRT)的妇女患乳腺癌的风险增加，然而，这种激素使用形式对乳腺癌死亡率的潜在影响尚未得到彻底的研究，目前我们对这种影响的了解(如果有的话)是不完整的。我们建议对加拿大萨斯喀彻温省1990年至2007年的乳腺癌死亡进行一项基于人群的嵌套病例对照研究，方法是将几个省级数据文件联系起来，包括人口登记、生命统计登记、萨斯喀彻温省癌症登记、处方药计划、医院服务、医生服务和乳腺癌筛查计划。在萨斯喀彻温省卫生保健(一个公共资助的卫生保健系统)登记的每个人都有一个唯一的卫生服务号，使个人的记录能够在这些数据文件中链接。这些数据的可获得性将使我们能够相对有效地评估乳腺癌死亡风险与CHRT使用的持续时间、近期和类型的关系，包括总体上和特定组织类型(导管和小叶)的乳腺癌。 公共卫生相关性： 近年来的流行病学研究发现，在接受联合激素替代治疗(CHRT)的绝经后妇女中，乳腺癌发病率增加。然而，尚不清楚的是，发病率的增加将在多大程度上转化为乳腺癌死亡率的增加--只有一项研究比较了启动和不启动CHRT的非乳腺癌女性的乳腺癌死亡率--这项研究的结果也没有定论。由于CHRT继续被广泛使用(目前约有200万美国妇女正在接受这种治疗)，而且CHRT的益处必须与风险进行权衡，因此评估CHRT使用者的乳腺癌死亡率是一项重要的工作。

DESCRIPTION (provided by applicant): Project Summary It has become increasingly evident that women who are taking combined hormone replacement therapy (CHRT) are at an increased risk of developing breast cancer, however, the potential impact of this form of hormone use on breast cancer mortality has not been thoroughly studied, and, at present our knowledge of this impact (if any) is incomplete. We propose to conduct a population-based nested case-control study of breast cancer deaths from 1990 through 2007 in Saskatchewan, Canada by linking several provincial-level data files, including the population registry, vital statistics registry, Saskatchewan Cancer Registry, Prescription Drug Plan, hospital services, physician services, and the Breast Cancer Screening Program. Each person registered with Saskatchewan Health (a publicly funded health care system) has a unique Health Services Number which enables an individual's records to be linked across these data files. The availability of these data will permit a relatively efficient assessment of the risk of breast cancer death in relation to the duration, recency, and type of CHRT use, both overall and for specific histologic types (ductal and lobular) of breast cancer. PUBLIC HEALTH RELEVANCE: Relevance In recent years epidemiologic studies are reasonably clear in their findings of an increased breast cancer incidence in postmenopausal women who have taken combined hormone replacement therapy (CHRT). However, what is not clear is the degree to which the increase in incidence will translate into an increase in breast cancer mortality - only a single study has compared mortality rates from breast cancer among women without breast cancer who do and do not initiate CHRT - and the results from this study were inconclusive. Because CHRT continues to be widely used (some two million American women are receiving this treatment at the present time), and because CHRT has benefits that have to be weighted against the risks, an assessment of breast cancer mortality in CHRT users represents an important undertaking.