Abstract D115: The interplay between rurality-urbanicity and race in prostate cancer risk, treatment, and survival in the United States
Authors: Butler Eboneé N , Cook Michael B 
Published: September 2020

Abstract
Background. In this study, we compared prostate cancer incidence and survival between rural and urban settings in the US, using a recently released census-tract rurality-urbanicity metric that serves as a proxy for geographical access to care. We also examined the associations between rurality and receipt of definitive treatment and further examined whether rural-urban status serves as an explanatory factor for observed race differences in prostate cancer incidence, treatment, and survival. Methods. Using data from the Surveillance, Epidemiology, and End Results program we identified prostate cancer patients newly diagnosed between 2000 and 2015, aged 45 years and older. Patients were classified as residing in a ‘rural’ or ‘urban’ setting based on the US Department of Agriculture’s 2-level Rural Urban Commuting Area (RUCA) measure. We defined ‘definitive treatment’ as receipt of radical prostatectomy (RP) among patients diagnosed with locoregional disease. To compare rural and urban settings we estimated relative measures for prostate cancer incidence, odds of treatment receipt, and prostate cancer survival using Poisson, logistic, and Cox regression models, respectively. We adjusted regression models for age, race, stage, or treatment, where applicable. Results. Between 2000 and 2015, men in the rural US were slightly less likely to be diagnosed with prostate cancer when compared with urban US men (incidence rate ratio (IRR) = 0.89; 95% CI: 0.88, 0.90), but were at higher risk of prostate cancer death (hazard ratio (HR) = 1.16; 95% CI: 1.13, 1.19). Patients diagnosed with locoregional disease in rural settings were also less likely to receive RP compared with their urban counterparts (odds ratio (OR) = 0.91; 95% CI: 0.89, 0.92) and were more likely to receive non-radical surgical interventions (OR = 1.31; 95% CI: 1.28, 1.35). In general, race differences were not evident by rural-urban status. Black men, however, were more likely to receive a prostate cancer diagnosis irrespective of geographical setting when compared with white men (rural IRR = 1.50; 95% CI: 1.46, 1.54 and urban IRR = 1.69; 95% CI: 1.64, 1.73). Black men were also substantially less likely to receive RP (OR = 0.49; 95% CI: 0.48, 0.49). With respect to survival, Asian or Pacific Islander men were at lower risk of prostate cancer death compared with white men (HR = 0.78; 95% CI: 0.75, 0.81). By contrast, American Indian/Alaskan Native and black men had the highest risks of death (HR = 1.26; 95% CI: 1.11, 1.43 and HR = 1.25; 95% CI: 1.22, 1.28, respectively). Conclusions. Observed differences in prostate cancer incidence, treatment, and survival may reflect spatial differences in access to cancer prevention and cancer care. Rural-urban status does not appear to modify racial/ethnic differences in prostate cancer incidence and survival.
Citation Format: Eboneé N Butler, Michael B Cook. The interplay between rurality-urbanicity and race in prostate cancer risk, treatment, and survival in the United States [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D115.