Hispanic and Asian American/Pacific Islander ethnic enclave, neighborhood socioeconomic status, and renal cell carcinoma incidence in California

BACKGROUND: We evaluated associations of neighborhood socioeconomic status (nSES) and ethnic enclave with renal cell carcinoma (RCC) incidence among Hispanic and Asian American/Pacific Islander (AAPI) populations in California. METHODS: We conducted a population-based study of 7,507 Hispanic and 2,293 AAPI individuals diagnosed with RCC in the California Cancer Registry across three Census periods (1988-1992, 1998-2002, and 2008-2012). Race- and ethnicity-specific Census population counts were used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) across nSES and ethnic enclave quintiles and joint variable of dichotomous nSES (high vs. low) and ethnic enclave (enclave vs. non-enclave). RESULTS: Higher nSES was associated with higher RCC incidence among AAPI individuals (Q5 vs. Q1: IRR=1.50; 95% CI, 1.27-1.78) and modestly elevated incidence among Hispanic individuals in intermediate quintiles. Less ethnically distinct neighborhoods were associated with higher incidence among Hispanic individuals (Q1 vs. Q5: IRR=1.21; 95% CI, 1.10-1.34), whereas no clear pattern was observed among AAPI individuals. Compared with low nSES/enclave neighborhoods, RCC incidence was higher in all other joint nSES/enclave categories in both populations. These associations were generally similar by sex, age at diagnosis, and tumor histology and were mainly observed for localized stage RCC. CONCLUSIONS: Hispanic and AAPI individuals living in higher-nSES neighborhoods had higher RCC incidence, while Hispanic individuals living in less ethnically distinct neighborhoods had higher RCC incidence. These patterns may reflect differences in healthcare access, diagnostic intensity, and neighborhood-related etiologic factors. IMPACT: Neighborhood factors should be considered in RCC etiology, surveillance, and risk stratification research among diverse populations.