Abstract Introduction: Breast (BC) and cervical (CC) cancers are leading causes of cancer incidence among Asian American (AA) women. Residing in ethnic enclaves may influence BC and CC outcomes among AA women. Ethnic enclaves are spatially clustered areas with a high density of a specific ethnic population that is distinct from the general population and many AA groups tend to reside in ethnic enclaves upon immigrating to the United States, primarily drawn to shared social networks and familiar climates. The current scope of literature on ethnic enclaves and cancer among AA is limited with evidence being inconclusive, likely due to the lack of disaggregation of AA subgroups. It is important to disaggregate AA subgroups, as the cancer risk profile of one subgroup is likely to differ from another due to their cultural and socioeconomic differences. Thus, we evaluated the associations between residing in ethnic enclaves with late-stage BC and CC risk by 2 AA subgroups. Methods: We identified Chinese and Vietnamese women diagnosed with either BC or CC in southern California between 2011 and 2020 using the California Cancer Registry. We defined a BC specific ethnic enclave and a CC specific ethnic enclave by using a novel case-based method, which evaluated the geospatial distribution of BC and CC cases separately using a cancer kernel density surface. Logistic regressions evaluated the association between ethnic enclave and late-stage BC and CC risk separately. The statistical models were stratified by AA subgroups and adjusted for age at diagnosis, nativity, marital status, insurance status, socioeconomic status, and comorbidities. Results: Our sample contained 5,456 Chinese Americans and 2,628 Vietnamese Americans diagnosed with either BC or CC. There was a total of 7,638 BC cases and 446 CC cases. We found that Chinese Americans residing in ethnic enclaves are 1.19 times as likely to be diagnosed with late-stage BC compared to Chinese Americans living outside the enclaves (95%CI: 1.04, 1.36, p=0.01). We did not find a statistically significant association between ethnic enclaves and late-stage BC risk among Vietnamese Americans (OR= 1.10, 95%CI: 0.91, 1.33, p=0.33). When assessing the association between ethnic enclaves and late-stage CC risk, we found a protective effect among those living inside the ethnic enclaves compared to their counterparts living outside, however, the associations were not statistically significant for either subgroup (Chinese American OR:0.80, 95%CI: 0.44, 1.48, p=0.48; Vietnamese American OR: 0.80, 95%CI: 0.35, 1.81, p=0.59). Conclusions: Our findings may suggest that the impacts of ethnic enclaves on cancer risk are cancer site and AA subgroup specific. Future studies should consider focusing on individual cancer sites and disaggregating ethnic subgroups when using ethnic enclaves to determine appropriate interventions. Citation Format: Michelle Tran, Sue E. Kim, Kali Zhou, Lihua Liu, Kimberly A. Miller, Myles Cockburn. Exploring the impacts of ethnic enclaves on late-stage breast and cervical cancer risk among Chinese and Vietnamese Americans in southern California abstract. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr A089.
Tran et al. (Thu,) studied this question.