Abstract B093: Residence within Hispanic ethnic enclaves is associated with later stage breast cancer diagnosis among Hispanic women in four U.S. states
Authors: Pruitt Sandi L. , Rathod Aniruddha B. , Shahan Kathryn L. , Canchola Alison J. , Boscoe Francis P. , Henry Kevin A. , Hiatt Robert A. , Hughes Amy E. , Lin Katherine , Meltzer Dan , Pinheiro Paulo S. , Stroup Antoinette M. , Zhu Hong , Gomez Scarlett L. , Shariff-Marco Salma 
Published: December 2023

Abstract
Background/Objective: Many Hispanic or Latino/a individuals (hereafter Hispanic) reside in ethnic enclaves. Hispanic enclaves are places characterized by high prevalence of Hispanic individuals, immigrants, individuals who speak Spanish, and/or ethnic-specific businesses. This population-based study of Hispanic women with breast cancer examines how residence in Hispanic enclaves is associated with late stage diagnosis. Methods: We used data from population-based cancer registries in four states (CA, NJ, NY, TX) to identify Hispanic women with breast cancer diagnosed between 2000-2017. Hispanic enclaves were defined using principal components analysis of four census tract-level variables: percent Hispanic, percent foreign-born Hispanic residents, percent with limited English and percent linguistically isolated and speaking Spanish. All census tracts in the four states were classified into quintiles of ethnic enclave score (pooled across all four states). Using log binomial regression with clustering by census tract, we examined associations of enclave residence (in quintiles) on late stage (regional or distant) compared to early stage (in-situ or localized) diagnosis; we fit unadjusted and adjusted models with age, year of diagnosis, insurance type, state, metropolitan/non-metropolitan census tract residence, and census tract percent poverty as covariates. Results: Among 165,226 Hispanic women, 35.1% were diagnosed at late stage. Two-thirds of women resided in census tracts with the highest ethnic enclave scores: 25.3% in Q4 and 43.6% in Q5. The percent late stage varied by ethnic enclave quintile (29.5% in Q1 to 37.9% in Q5; Chi-square across all quintiles p&lt;0.01. Residence in the highest (Q5) compared to lowest (Q1) enclave quintile was associated with increased risk of late-stage diagnosis in the unadjusted model (RR=1.28 95% CI: 1.24-1.33) and in the fully adjusted model (RR=1.11; 95% CI: 1.07-1.15). Conclusions: Enhanced understanding of the features of ethnic enclaves that may contribute to later stage at breast cancer diagnosis among Hispanic women is important to inform future outreach and intervention. Additional analyses will assess potential for moderation by poverty and will examine whether results vary by enclave characteristics such as the predominant ethnic group (e.g., Mexican, Puerto Rican) or enclave transitions between 2000-2010 (never, former, persistent, emerging enclave).
Citation Format: Sandi L. Pruitt, Aniruddha B. Rathod, Kathryn L. Shahan, Alison J. Canchola, Francis P. Boscoe, Kevin A. Henry, Robert A. Hiatt, Amy E. Hughes, Katherine Lin, Dan Meltzer, Paulo S. Pinheiro, Antoinette M. Stroup, Hong Zhu, Scarlett L. Gomez, Salma Shariff-Marco. Residence within Hispanic ethnic enclaves is associated with later stage breast cancer diagnosis among Hispanic women in four U.S. states [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B093.