Anti-inflammatory vs. inflammatory treatments for actinic keratoses

The treatment of actinic keratoses (AKs) provides an important opportunity to prevent the development of squamous cell carcinoma. The recent discovery that cyclo-oxygenase-2 (COX-2) is a potential pharmacological target for skin tumours has prompted interest in using topical nonsteroidal anti-inflammatory drugs (NSAIDs) as a treatment for AKs. Topical 3% diclofenac in 2.5% hyaluronic acid gel (Solaraze) is currently the only NSAID licensed for the treatment of AKs. In randomised, double-blind studies, this therapy was effective in clearing AKs, with the efficacy increasing in proportion to the duration of treatment. Topical 3% diclofenac in 2.5% hyaluronic acid gel was well tolerated, with the vast majority of adverse events rated as mild or moderate. Older treatments, such as fluorouracil, which promotes an inflammatory response, are also effective in treating AKs, but are not acceptable to many patients because of severe irritation. Imiquimod is an alternative inflammatory treatment, which, although highly effective, is expensive and produces severe erythema, erosion and flaking in a large proportion of patients. Topical anti-inflammatory agents, such as 3% diclofenac in 2.5% hyaluronic acid gel, can facilitate the early treatment of AKs without the level of severe side-effects observed with some of the other therapies.