NSAIDs May Protect Against Cutaneous Squamous Cell Carcinoma

Non-steroidal anti-inflammatory drugs (NSAIDs), including aspirin, may protect against cutaneous squamous cell carcinoma (cSCC), according to the results of a meta-analysis. Cutaneous SCC risk was reduced by 15% among those who used non-aspirin NSAIDs and by 18% among those who used any NSAID, including aspirin. There was a 12% risk reduction among those who took aspirin, but this result was not statistically significant. 

Those individuals with a high degree of actinic keratoses--growths that are potentially precancerous or a history of skin cancer--had the highest reduction in risk.

The study is published in the Journal of Investigative Dermatology.

Catherine Olsen and Adèle Green, of the QIMR Berghofer Medical Research Institute in Brisbane, Australia, and colleagues reviewed nine previously published epidemiological studies on the link between aspirin and other NSAID use, and the risk of cSCC.

Previous studies have provided hints that NSAIDs could be protective against certain types of cancer, including colorectal and prostate cancer.

“Clinicians can now take this into consideration when prescribing anti-inflammatory medication for their patients with other sun-induced skin tumors who may be at high risk of SCC,” Olsen told OncoTherapy Network via email.

While all nine of the studies assessed a potential dose-response link between NSAID use and cSCC, only one study reported a statistically significant (P =.05) relationship.

The authors suggest that the potential anti-cancer mechanism of NSAIDS may be due to their inhibition of cyclooxygenase (COX-2), an enzyme that is released as a result of ultraviolet light exposure. However, the current analysis was not able to take into account sun exposure of individuals in the studies. “We believed that it is possible that NSAIDs protect against SCC because chronic exposure to ultra-violet radiation-the main cause of SCC-damages the skin cells resulting in the release of factors including COX-2 and its product, prostaglandin E2 which influence skin carcinogenesis,” Olsen said. “NSAIDs inhibit COX-2 and suppress production of prostaglandins and thus may have chemopreventive effects on SCC.”

A similar pooled analysis did not find that NSAIDs protect against melanoma and the evidence so far for cSCC is inconclusive.

“These findings are now the subject of further research at the QIMR Berghofer, including the examination of dose and duration of use of NSAIDS in relation to SCC,” said Olsen.