A Cochrane review included 16 studies (seven statin, nine fibrate). Thirteen trials (62 197 participants) provided data on incident melanomas (six statin, seven fibrate). A total of 66 melanomas were reported in groups receiving the experimental drug and 86 in groups receiving placebo or other control therapies. For statin, the odds ratio (OR) was 0.90 (95% confidence interval 0.56 to 1.44) and for fibrate trials OR was 0.58 (95% CI 0.19 to 1.82).
Comment: The quality of evidence is downgraded by imprecise results (few outcome events) and by potential reporting bias (only favourable results published).