Non-steroidal anti-inflammatory drug and aspirin use and the risk of head and neck cancer: a systematic review.

Background: Use of non-steroidal anti-inflammatory drugs (NSAIDs) has been associated with a reduced risk of several cancers. This is thought to be through the inhibitory action on the cyclooxygenase (COX) enzyme, COX-2. Evidence for NSAIDs preventing head and neck cancer (HNC) is conflicting. We conducted a systematic literature review to investigate the association between NSAID/aspirin use and risk of head and neck cancer (HNC). Methodology: MEDLINE, EMBASE, PubMed, Cochrane Library, and Web of Science were systematically searched using terms for NSAIDs/aspirin, HNC, and observational/intervention study designs to identify studies published by December 2009. Results: Of 9,268 articles identified, two population-based prescribing database studies and three case-control studies met the selection criteria. The studies investigated different HNC sites. Only one study found a significant protective association of aspirin use with HNC risk (OR 0.75, 95% CI 0.58-0.96), and one showed a significantly increased risk of oral/oropharyngeal cancer with non-low-dose aspirin NSAID use (OR 3.5, 95% CI 1.8-6.7). Many of the studies identified lacked information on important confounding factors. Conclusion: No definitive conclusion on the effect of NSAIDs/aspirin on HNC risk was possible. Aspirin may protect against HNC, although further robust large-scale studies are required to clarify any possible association. [ABSTRACT FROM AUTHOR]