Background: Men of African descent experience a disproportionately high prostate cancer mortality. Intratumoral inflammation was found to be associated with aggressive prostate cancer. We and others have shown that prostate tumors in African-American (AA) patients harbor a distinct immune and inflammation signature when compared with European-American (EA) patients. These observations suggest that inflammation could be a driver of aggressive disease in men of African descent, leading to the hypothesis that an anti-inflammatory drug like aspirin could prevent disease progression.Methods: We examined the relationship between aspirin use and prostate cancer in the NCI-Maryland Prostate Cancer Case-Control Study consisting of 823 men with incident prostate cancer (422 AA and 401 EA) and 1,034 population-based men without the disease diagnosis (486 AA and 548 EA).Results: We observed a significant inverse association between regular aspirin use and prostate cancer among AA men. Stratification of AA patients by disease stage showed that daily and long-term (>3 years) aspirin use significantly decreased the risk of advanced disease [adjusted ORs for T3/T4 disease: 0.35, 95% confidence interval (CI), 0.17-0.73; and 0.22, 95% CI, 0.08-0.60, respectively], but not early-stage disease (T1/T2). Regular aspirin use also reduced disease recurrence in AA men.Conclusions: Regular aspirin use is associated with a decreased risk of advanced stage prostate cancer and increased disease-free survival in AA men.Impact: Regular aspirin use before and after a prostate cancer diagnosis may prevent the development of aggressive disease in AA men who are at risk of a lethal malignancy. Cancer Epidemiol Biomarkers Prev; 26(6); 845-53. ©2017 AACR.
©2017 American Association for Cancer Research.