By David Liu, PHD

Tuesday Sept 4,  2012 (foodconsumer.org) -- A new study recently published in Journal of Clinical Oncology suggests that patients with localized prostate cancer who receive prostatectomy or radiotherapy may reduce risk of death from the disease by taking aspirin. This is not a trial, and a causal relation has not been established, meaning it remains unknown whether taking aspirin may be responsible for the decrease in the risk.

Previous research suggests that anticoagulants like aspirin may inhibit cancer growth and metastasis. The current study was intended to investigate whether use of anticoagulants was associated with risk of death from prostate cancer in patients who received cancer treatments.

Involved in the study were 5,955 men in the Cancer of the Prostate Strategic Urologic Research Endeavor database with localized prostate cancer treated with either radical prostatectomy or radiotherapy.  Of them, 2,175 (37%) were receiving anticoagulants including warfarin, clopidogrel, enoxaparin, and/or aspirin.

During a median follow-up of 70 months, risk of prostate cancer specific death was found significantly lower in the anticoagulants group, compared with the non-anticoagulants group at 10 years, 3% vs. 8%. The risks of prostate cancer recurrence and bone metastasis were also significantly lower. 

Among the patients with high risk disease, the prostate cancer specific mortality in those anticoagulant users at 10 years was 4% compared to 19% in those non-users. 

The benefit from anticoagulants was observed across treatment modalities including radiotherapy or radical prostatectomy. 

Among various anticoagulants, aspirin was found most strongly associated with the reduction in prostate cancer specific death risk.  Multivariate analysis showed those who received not only cancer treatments, but also aspirin were 57 percent less likely to die from prostate cancer, compared to those who only received cancer treatments.

Stanley L. Liauw of University of Chicago Hospital in Chicago, IL and colleagues, authors of the study, concluded "AC (anticoagulants) therapy, particularly aspirin, was associated with a reduced risk of PCSM (prostate cancer specific mortality) in men treated with RT (radiotherapy) or RP (radical prostatectomy) for prostate cancer. The association was most prominent in patients with high-risk disease."

It should be noted that research has suggested that patients with localized prostate cancer who received radical prostatectomy did not reduce their all-cause mortality, compared to those who received observation only.  

The current study established the link between use of aspirin and risk of death from prostate cancer in patients who had received radiotherapy or radical prostatectomy.  But it remains unknown whether this finding is applicable to patients who receive observation only.

Long term oral use of aspirin can lead to some side effects including gastrointestinal ulcers, stomach bleeding, and tinnitus, especially when higher doses are used.