RESUMEN
Background: There is an increase in the incidence of malignant melanoma in Chile. Previous studies have shown that the density and size of acquired melanocytic nevi (AMN) are a risk factor for developing malignant melanoma. Aim: To assess the number and anatomical distribution of acquired melanocytic nevi in Chilean adolescents. Material and methods: The number of AMN was counted in 30 anatomical sites in 201 Chilean school children (111 females), aged from 11 to 15 years. The number oí small AMN (2-4.9 mm) and large AMN (>5 mm ofdiameter) was determined. Results: Mean AMN number per person was 32.7 (95 percent confidence interval (CI) 30.7-42.3) in males and 29 (95 percent CI 271-38.6) in females (p =NS). Males had a higher number of AMN in the face, neck and trunk. Females had a higher number of AMN in the upper and lower limbs. Older children, adolescents with history of sunburns and with lighter skin had a higher number of total, small and large nevi. Conclusions: The average number ofAMNfound in this study is similar to that reported in the literature. The differences in site distribution between males and femalesmay be explainedby a differentsun exposurepattern.