REGIONAL VARIATIONS IN BREAST CANCER RATES IN CALIFORNIA

观察到的乳腺癌发病率的区域差异一直是公共卫生关注的一个来源，也是传统上对可能与疾病病因有关的因素产生假设的一个来源。加州内部的差异与全国范围内的差异相似。该提案旨在探索可能解释加州观察到的区域差异的因素。该研究的具体目的是：利用地理信息系统（GIS）和分组数据源来评估社会人口因素（如收入、教育）、环境毒物(如：（如农药、汽车尾气），以及确定的风险因素（如家族史、生殖风险因素）对加州乳腺癌发病率地区差异的影响；通过纳入一项针对加州教师的大型前瞻性队列研究的个体风险因素信息，进一步评估目标1中确定的区域关联，该研究专门用于研究乳腺癌的风险因素；并开展一项生物标志物亚研究，旨在探索乳腺癌研究中新兴兴趣的两种特定暴露（即植物雌激素和多环芳烃）的生物标志物的城市/农村差异。全州分组分析将依赖多种数据来源，包括世界上最大的癌症登记处，两个全州风险因素调查，多个全州环境数据集和人口普查数据。个人层面的风险因素信息将来自133,400名参加加州教师研究（CTS）队列的女教师，她们分布在整个州。生物标志物亚研究将在该队列中进行，并将在130名城市和130名农村CTS成员中进行，以评估与乳腺癌区域差异可能相关的饮食和环境标志物暴露。这些多种数据来源，加上地理信息系统的使用，提供了一个独特的机会，将个人风险因素信息与潜在的重要社区因素结合起来，这是迄今为止没有其他研究做过的。此外，生物标志物亚研究将使我们能够在城市/农村乳腺癌发病率差异的背景下评估两种关于乳腺癌病因学的新兴和有趣的假设。

Observed regional variations in breast cancer incidence have been a source of public health concern as well as traditionally a source of hypothesis generation for factors which might be implicated in disease etiology. Rate differences within California are similar to differences noted on the national scale. This proposal is designed to explore factors that may explain the observed regional variations within California. The specific aims of the study are to: use a geographic information system (GIS) and grouped data sources to evaluate the potential influence of sociodemographic factors (e.g., income, education), environmental toxicants(e.g., pesticides, automobile exhaust), and established risk factors (e.g., family history, reproductive risk factors) on regional differences in breast cancer incidence rates in California; further evaluate regional associations identified in Aim 1 by incorporating individual risk factor information from a large, prospective cohort study of California teachers specifically designed to study risk factors for breast cancer; and conduct a biomarker substudy targeted at exploring urban/rural variations in biological markers of two specific exposures of emerging interest in breast cancer research (i.e, phytoestrogens and polycyclic aromatic hydrocarbons). Statewide grouped analyses will rely on multiple sources of data including the largest cancer registry in the world, two statewide risk factor surveys, multiple statewide environmental datasets, and census data. Individual-level risk factor information will be derived from the 133,400 female teachers enrolled in the California Teacher Studies (CTS) cohort who are geographically dispersed throughout the state. The biomarker substudy will be nested within this cohort and will be conducted on 130 urban and 130 rural CTS members to evaluate both dietary and environmental markers for exposures potentially related to regional variations in breast cancer. These multiple sources of data, coupled with the use of a GIS system, offer a unique opportunity to integrate individual risk factor information with potentially important community-level factors in a way that no other study has done to date. Furthermore, the biomarker substudy will allow us to evaluate two emerging and intriguing hypotheses regarding breast cancer etiology in the context of urban/rural variations in breast cancer rates.