Regular use of selective COX-2 inhibitors decreases risk of breast cancer

Regular use of selective COX-2 inhibitors significantly reduces the risk of breast cancer. A case-control study published today in the open access journal BMC Cancer observed that daily use of selective COX-2 inhibitors, including celecoxib (Celebrex) and rofecoxib (Vioxx), was associated with a 71% reduction in the risk of breast cancer. Non-selective COX-2 inhibitors, such as aspirin and ibuprofen, also reduced the risk of breast cancer. This study highlights the potential of nonsteroidal anti-inflammatory drugs (NSAIDs) for the prevention of breast cancer.

Randall Harris and colleagues from The Ohio State University College of Medicine and Public Health, Columbus, Ohio, USA, collected data on 323 patients with invasive breast cancer shortly after their diagnosis. Harris et al. matched the patients for age, race and county of residence with 649 control individuals with no personal history of cancer. Data collected for patients and controls included information on breast cancer risk factors, and the use of selective COX-2 inhibitors and other NSAIDs.

Harris et al.’s results show that selective COX-2 inhibitors, as a group, were associated with a significantly reduced risk of breast cancer (OR=0.29) when taken daily for at least two years: a daily dose of 200 mg celecoxib reduced the risk of breast cancer by 83% and a daily dose of 25 mg rofecoxib reduced the risk of breast cancer by 64%. Regular use of non-selective COX-2 inhibitors – aspirin (325 mg), ibuprofen (200mg) and naproxen (250 mg) – also significantly reduced the risk of breast cancer, but less so than regular intake of selective COX-2 inhibitors. Ibuprofen and aspirin significantly decreased the risk of developing breast cancer when taken at least every other day for at least five years. Regular intake of acetaminophen, an analgesic lacking COX-2 activity, had no effect on the risk of breast cancer.