邻域层面的劣势是导致贫困地区不公平乳腺癌特异性生存率不足的重要因素。尽管研究已经在大型全国癌症数据库中评估了邻域层面劣势和个体级别社会经济状况（SES）对乳腺癌特异性生存的影响，但这些研究的年龄、社会经济和种族与 etnical的多样性限制了其研究范围。为了研究邻域SES（使用经过验证的综合综合指数）和多数少数人口中的乳腺癌特异性生存，该回顾性多机构队列研究包括在一个国家癌症研究所指定的癌症中心和一个姐妹安全网医院中接受治疗的 I 至 IV 期乳腺癌患者，时间跨度为 2007 年 1 月 10 日至 2016 年 9 月 9 日。平均（SD）随访时间为 60.3（41.4）个月，数据分析时间为 2022 年 3 月至 2023 年 3 月。邻域SES是使用区域剥夺指数（三分位数）测量的，这是一个验证的综合综合指数。主要结果为乳腺癌特异性生存。对乳腺癌特异性生存的随机效应脆性模型进行了分析，控制个体级别社会人口学、合并症、乳腺癌风险因素、医疗保健、肿瘤和国家综合癌症网络指南一致治疗特征。每个患者的区域剥夺指数是在普查分区水平上计算的，并分为三分位数（T1-T3）。总共包括了 5027 名乳腺癌患者，其中 55.8％ 是西班牙裔，17.5％ 是非西班牙裔黑人，27.0％ 是非西班牙裔白人。平均（SD）年龄为 55.5（11.7）岁。控制个体级别社会人口学、合并症、乳腺癌风险因素、医疗保健、肿瘤和国家综合癌症网络指南一致治疗特征后，在最不利劣的社区（T3）居住的妇女与居住在最有利的社区（T1）的妇女相比，乳腺癌特异性生存率较短（T3 vs. T1：风险比，1.29；95％CI，1.01-1.65; P <.04）。在这个队列研究中，发现了生活在劣势社区的妇女与生活在有利社区的妇女相比具有更短的乳腺癌特异性生存，即使在控制个体级别社会人口学、合并症、乳腺癌风险因素、医疗保健、肿瘤和国家综合癌症网络指南一致治疗特征之后。这些发现表明还存在未计算的社会健康决定因素和医疗保健措施等潜在机制。这项研究还为未来的研究奠定了基础，以评估生活在劣势社区的社会不利因素是否与更具侵略性的肿瘤生物学因素以及最终的更短乳腺癌特异性生存有关，通过社会基因组和/或表观基因组变化。

Neighborhood-level disadvantage is an important factor in the creation and persistence of underresourced neighborhoods with an undue burden of disparate breast cancer-specific survival outcomes. Although studies have evaluated neighborhood-level disadvantage and breast cancer-specific survival after accounting for individual-level socioeconomic status (SES) in large national cancer databases, these studies are limited by age, socioeconomic, and racial and ethnic diversity.To investigate neighborhood SES (using a validated comprehensive composite measure) and breast cancer-specific survival in a majority-minority population.This retrospective multi-institutional cohort study included patients with stage I to IV breast cancer treated at a National Cancer Institute-designated cancer center and sister safety-net hospital from January 10, 2007, to September 9, 2016. Mean (SD) follow-up time was 60.3 (41.4) months. Data analysis was performed from March 2022 to March 2023.Neighborhood SES was measured using the Area Deprivation Index (tertiles), a validated comprehensive composite measure of neighborhood SES.The primary outcome was breast cancer-specific survival. Random effects frailty models for breast cancer-specific survival were performed controlling for individual-level sociodemographic, comorbidity, breast cancer risk factor, access to care, tumor, and National Comprehensive Cancer Network guideline-concordant treatment characteristics. The Area Deprivation Index was calculated for each patient at the census block group level and categorized into tertiles (T1-T3).A total of 5027 women with breast cancer were included: 55.8% were Hispanic, 17.5% were non-Hispanic Black, and 27.0% were non-Hispanic White. Mean (SD) age was 55.5 (11.7) years. Women living in the most disadvantaged neighborhoods (T3) had shorter breast cancer-specific survival compared with those living in the most advantaged neighborhoods (T1) after controlling for individual-level sociodemographic, comorbidity, breast cancer risk factor, access to care, tumor, and National Comprehensive Cancer Network guideline-concordant treatment characteristics (T3 vs T1: hazard ratio, 1.29; 95% CI, 1.01-1.65; P < .04).In this cohort study, a shorter breast cancer-specific survival in women from disadvantaged neighborhoods compared with advantaged neighborhoods was identified, even after controlling for individual-level sociodemographic, comorbidity, breast cancer risk factor, access to care, tumor, and National Comprehensive Cancer Network guideline-concordant treatment characteristics. The findings suggest potential unaccounted mechanisms, including unmeasured social determinants of health and access to care measures. This study also lays the foundation for future research to evaluate whether social adversity from living in a disadvantaged neighborhood is associated with more aggressive tumor biologic factors, and ultimately shorter breast cancer-specific survival, through social genomic and/or epigenomic alterations.