INTRODUCTION Prostate cancer stands as one of the most diagnosed malignancies among men worldwide. With the recent expansion of Medicaid under the Affordable Care Act (ACA), millions more Americans now have health insurance coverage, potentially influencing healthcare access and subsequent outcomes for various illnesses, including prostate cancer. Yet, the direct correlation between Medicaid expansion and cancer-specific survival, particularly for early-stage prostate cancer, remains an area warranting comprehensive exploration. OBJECTIVE This study aims to determine the impact of the implementation of Medicaid expansion on Survival outcomes among men with prostate cancer. METHODS We utilized data from the SEER registry to determine the causal impact of the implementation of the ACA on outcomes among men with prostate cancer. The study covered the years 2003-2021, divided into pre-ACA (2003-2009) and post-ACA (2015-2021) periods, with a 1-year washout (2014-2015) since Medicaid expansion was implemented in 2014 in Kentucky. Using a Difference-in-Differences approach, we compared survival among men with prostate cancers from Kentucky to Georgia. We adjusted for patient demographics, income, metropolitan status, disease stage, and treatment modalities. RESULTS We analyzed a cohort of 68,222 men with prostate cancer during the study period. Of these, 37,810 (55.4%) were diagnosed in the pre-ACA period, with 70.8% from Georgia and 29.2% from Kentucky. The remaining 30,412 (44.6%) were diagnosed in the post-ACA period, with 72.3% from Georgia and 27.7% from Kentucky. Medicaid expansion in Kentucky was associated with a 16.8% reduction in hazard of death (HD), indicating improved overall survival among low-income individuals. This trend was consistent across different racial/ethnic groups. Specifically, Non-Hispanic white men experienced a 16.2% reduction (DID = -0.162, 95% CI: -0.315 to -0.008), Non-Hispanic Black men had a 17.9% reduction (DID = -0.179, 95% CI: -0.348 to -0.009), and Hispanic men saw a 15.9% reduction (DID = -0.159, 95% CI: -0.313 to -0.005) in HD among low-income individuals. CONCLUSION Medicaid Expansion was associated with a substantive improvement in overall survival among men with prostate cancers in Kentucky compared to non-expansion Georgia.

The authors have declared no competing interest.

The authors declare that no funding was received for the conduct of this study, preparation of the manuscript, or publication of this work.

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The data supporting the findings of this study are available on request from the corresponding author.