BACKGROUND: Statins show anticancer activity in melanoma cells. We investigated the association between statins and incidence and Breslow thickness of cutaneous melanoma (CM). METHODS: Data were used from PHARMO, a pharmacy database, and PALGA, a pathological database, in the Netherlands. Cases had a primary CM diagnosis between January 1st 1991 and December 14th 2004, were 18 years and had 3 years of follow up in PHARMO before CM diagnosis. Controls were matched for gender, date of birth and geographic region. Analyses were adjusted for age, gender, year of diagnosis, number of medical diagnoses and the use of NSAIDs and oestrogens. FINDINGS: Finally, 1318 cases and 6786 controls were selected. CM risk was not associated with statin use (> or = 0.5 years) (adjusted odds ratio (OR)=0.98, 95% confidence interval (CI)=0.78-1.2). However, statin use was associated with a reduced Breslow thickness (-19%, 95% CI=-33, -2.3, p=0.03). CONCLUSION: Our study suggests protective effects of statins on melanoma progression.