Sunscreen use, wearing clothes, and number of nevi in 6- to 7-year-old European children

Background: Previous epidemiologic studies have suggested that sunscreen us e is associated with an increased risk of melanoma skin cancer. Because hig h nevi (mole) count in adults is a strong predictor of melanoma, we conduct ed a study examining the number of nevi in 6- to 7-year-old European childr en, according to their sunscreen use, Methods: Whole-body and site-specific counts of nevi 2 mm or larger were performed in 631 children in their firs t year of primary school in four European cities. Independently, parents we re interviewed regarding sun exposure, sunscreen use, and physical sun prot ection of their child. Results: After adjustment for sun exposure and host characteristics (e,g,, skin phototype, eye color), the relative risk for hi gh nevus count on the trunk was 1.68 (95% confidence interval [CI] = 1.09-2 .59) for the highest level of sunscreen use and 0.59 (95% CI = 0.36-0.97) f or the highest level of wearing of clothes while in the sun. The sun protec tion factor had no effect on nevus counts despite a high median value of 17 .4, Sunburn number was not associated with nevus count. The highest risk as sociated with sunscreen use was found among children who had never experien ced sunburn. Conclusions: In white, European children, sunscreen use appear s to be associated with development of nevi, probably because it allows lon ger sun exposures. Wearing clothes may be an effective way to prevent proli feration of nevi, Since a high nevus count is a strong predictor of melanom a, sunscreen use may be involved in melanoma occurrence because it may enco urage recreational sun exposure.