Aspirin and Nonsteroidal Anti-Inflammatory Drugs Can Prevent Cutaneous Squamous Cell Carcinoma: a Systematic Review and Meta-Analysis

Nonsteroidal anti-inflammatory drugs (NSAIDS) have received increasing attention as potential chemopreventive agents of skin cancer, but evidence is inconsistent. To investigate whether the use of aspirin and other NSAIDS reduces the risk of squamous cell carcinoma (SCC), we conducted a systematic review on the basis of published epidemiologic studies and calculated summary estimates for aspirin, nonaspirin NSAIDS, and any NSAIDS use. Summary estimates from nine studies (five case control, three cohort, and one intervention) indicated significantly reduced risks of SCC among users of nonaspirin NSAIDS (relative risk (RR) 0.85, 95% confidence interval (Cl) 0.78-0.94) and among users of any NSAIDS (RR 0.82, 95% Cl 0.71-0.94) compared with nonusers with the effect seen particularly in those with previous actinic skin tumors. A reduced risk was also observed among aspirin users, although with borderline statistical significance (RR 0.88 95% Cl 0.75-1.03). There was significant heterogeneity between studies regarding SCC risk estimates for aspirin use and any NSAIDS use. These findings suggest that NSAIDS collectively have the potential to prevent the development of cutaneous SCC.