Aspirin use decreases the risk of prostate cancer recurrence after post-prostatectomy radiotherapy

Abstract

Objectives: The objective of the study is to determine if aspirin use is associated with decreased risk of biochemical failure, distant metastasis, and prostate cancer specific mortality in prostate cancer patients after adjuvant or salvage radiation therapy following radical prostatectomy. Methods: We identified 189 men with pathologic T2a-4a, N0/X, M0 prostate adenocarcinoma who received adjuvant or salvage radiation therapy following prostatectomy. Aspirin use (defined as use at time of radiation therapy or during follow-up) was present in 60 men (32 %). Cox multivariate analysis was performed using Kaplan-Meier estimation and log-rank test with the following covariates: pre-radiation therapy prostate-specific antigen, Gleason score, prostate-specific antigen doubling time, warfarin or clopidogrel use, aspirin use, surgical margin status, radiation dose, time interval from prostatectomy to radiation therapy, and radiation technique. Results: The median follow-up time was 50 months. Aspirin use was associated with improved 5-year rates of prostate-specific antigen nadir + 2 ng/mL biochemical failure (15 vs. 42 %, p = 0.002), distant metastases (0 vs. 8 %, p = 0.02), and prostate cancer-specific mortality (0 vs. 5 %, p = 0.14). On multivariate analysis, aspirin nonuse (hazard ratio = 2.9, 95 % confidence interval = 1.3–6.6) was the only predictor for prostate-specific antigen nadir + 2 ng/mL biochemical failure. Conclusion: In patients who received adjuvant and salvage radiation therapy after primary radical prostatectomy, aspirin use was associated with a decreased risk of biochemical failure.