Study objective: To explore the association between exposure to acetaminophen (paracetamol) or nonsteroidal antiinflammatory drugs (NSAIDs) and risk of developing ovarian, breast, or colon cancer.
Design: Retrospective case-control study
Setting: General practice offices.
Subjects: Four hundred eighty-three women with ovarian cancer and 1877 women matched for age, years of medical history in computer record, general practice attended, and calendar time; 3706 women with breast cancer and 14,155 matched control subjects; and 635 women with colon cancer and 2434 matched control subjects.
Intervention: United Kingdom-based General Practice Research Database was searched for women aged 50-89 years with a first-time diagnosis of ovarian, breast, or colon cancer and for matched controls to assess prescription analgesic exposure.
Measurements and main results: Regular acetaminophen exposure (> or = 30 prescriptions) was associated with a slightly decreased risk of developing breast (odds ratio [OR] 0.8, 95% confidence interval [CI] 0.7-1.0) but not ovarian (OR 1.0, 95% CI 0.6-1.5) or colon (OR 1.0, 95% Cl 0.7-1.4) cancer. Regular NSAID exposure was associated with a reduced risk of colon (OR 0.5, 95% CI 0.3-0.9) but not ovarian or breast cancer.
Conclusion: We found no evidence for a decreased ovarian cancer risk for women with regular acetaminophen or NSAID exposure.