Analysis of 135,095 Ohio men diagnosed with prostate cancer from 1996-2016 reveals that Black men face 79% higher odds of metastatic disease at diagnosis compared to White men. The study found that neighborhood deprivation, measured by Area Deprivation Index, and insurance status together reduced this disparity by approximately 40% - from an odds ratio of 1.79 to 1.41 after adjustment. Black men lived in significantly more deprived neighborhoods (median ADI 60.9 vs 47.3) and were more likely to have Medicaid coverage, which carried the highest risk for late-stage diagnosis. This population-based analysis provides compelling evidence that structural inequities contribute substantially to prostate cancer disparities, though biological and other unmeasured factors likely account for the remaining gap. The findings align with decades of research on social determinants of health, suggesting that interventions targeting neighborhood-level resources and healthcare access could meaningfully reduce cancer disparities. However, as this is a preprint awaiting peer review, these conclusions require validation through the rigorous editorial process. The persistence of unexplained racial differences even after extensive adjustment highlights the complex, multifactorial nature of health disparities that extends beyond measurable socioeconomic factors.