Prostate Cancer Incidence and Aggressiveness in Appalachia versus Non-Appalachia Populations in Pennsylvania by Urban-Rural Regions, 2004-2014

Background: Few studies have examined prostate cancer incidence and aggressiveness in urban-rural Appalachian populations. We examined these rates in urban-rural Appalachia and non-Appalachia Pennsylvania (PA), and the association between these areas and more aggressive prostate cancer at diagnosis. Methods: Men, ages >= 40 years with a primary prostate cancer diagnosis, were identified from the 2004-2014 Pennsylvania Cancer Registry. Age-adjusted incidence rates for prostate cancer and more aggressive prostate cancer at diagnosis were calculated by urban-rural Appalachia status. Multivariable Poisson regressions were conducted. Multiple logistic regressions were used to examine the association between the geographic areas and more aggressive prostate cancer, after adjusting for confounders. Results: There were 94,274 cases, ages 40-105 years, included. Urban non-Appalachia had the highest 2004-2014 age-adjusted incidence rates of prostate cancer and more aggressive prostate cancer (293.56 and 96.39 per 100,000 men, respectively) and rural Appalachia had the lowest rates (256.48 and 80.18 per 100,000 men, respectively). Among the cases, urban Appalachia were more likely [OR = 1.12; 95% confidence interval (CI) = 1.08-1.17] and rural Appalachia were less likely (OR - 0.92; 95% CI = 0.87-0.97) to have more aggressive prostate cancer at diagnosis compared with urban non-Appalachia. Conclusions: Lower incidence rates and the proportion of aggressive disease in rural Appalachia may be due to lower prostate cancer screening rates. More aggressive prostate cancer at diagnosis among the cases in urban Appalachia may be due to exposures that are prevalent in the region. Impact: Identifying geographic prostate cancer disparities will provide information to design programs aimed at reducing risk and closing the disparity gap.