Differences in the impact of aspirin in various forms of cancer are highlighted in two studies published online ahead of print by Journal of Clinical Oncology.
In one study, Kevin S. Choe, MD, and colleagues found the risk of prostate cancer-specific mortality (PCSM) to be significantly lower in 2,175 men who were receiving anticoagulants (warfarin, clopidogrel, enoxaparin, and aspirin) than in 3,780 men who were not. The men had all undergone radical prostatectomy or radiotherapy for localized adenocarcinoma of the prostate. The risks of disease recurrence and bone metastasis were also significantly lower among the anticoagulant users.
Yet in another large study, Xuehong Zhang and fellow researchers found no important association between the risk of postmenopausal breast cancer and the use of aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and acetaminophen.
Zhang’s team observed 84,602 postmenopausal women, who were free of cancer in 1980, until June 2008. Throughout the course of the study, 4,734 cases of incident invasive breast cancer were documented.
Compared with nonuse of aspirin, multivariable relative risks of regular aspirin use (two or more tablets per week) for more than 20 years were 0.91 for overall breast cancer, 0.90 for estrogen receptor (ER)-positive progesterone receptor (PR)-positive breast cancer, and 0.91 for ER-negative PR-negative breast cancer.
Results did not vary appreciably by past or current aspirin use, days per week of use, or dosage of use. Use of other NSAIDs and acetaminophen was largely not significantly associated with breast cancer risk, nor was use of higher doses of each analgesic (six or more tablets per week) for more than 10 years. ONA