Melanocytic Nevi and Sun Exposure in a Cohort of Colorado Children: Anatomic Distribution and Site-Specific Sunburn

Department of Pediatrics, University of Colorado, Denver, Colorado, United States
Cancer Epidemiology Biomarkers & Prevention (Impact Factor: 4.13). 10/2007; 16(10):2136-43. DOI: 10.1158/1055-9965.EPI-07-0453
Source: PubMed


Sun exposure and high prevalence of melanocytic nevi are major risk factors for melanoma, but the relationship between them is not well understood. This study examines the relationship between sun exposure (detailed by anatomic location and history of site-specific sunburns) and the presence of melanocytic nevi on 743 White children in Denver, Colorado. Parental reports of site-specific sunburns were collected annually for 2 years starting at ages 5 to 6 years. In the third year, nevi were counted and mapped by anatomic location. Nevus density was higher for boys (36.0 nevi/m2) than for girls (31.0 nevi/m2; P = 0.04). Nevus density was highest on the face, neck, and lateral forearms and was significantly higher in chronically versus intermittently sun-exposed areas (P < 0.0001). Compared with girls, boys had higher nevus density on the face, neck, and trunk, and lower nevus density on the upper arms and thighs (P < 0.01). In 2 years of reports, most subjects (69%) received at least one sunburn. The face, shoulders, and back were the most frequently sunburned areas of the body. When adjusted for host factors, total number of sunburns was significantly associated with higher total nevus prevalence (P = 0.01 for one burn). Site-specific sunburns were significantly associated with nevus prevalence on the back (P = 0.03 for three or more sunburns), but not on the face, arms, or legs. In this high-risk population, there is evidence for two pathways to nevus accumulation: by chronic sun exposure and by intermittent exposure related to sunburns.

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Available from: Nancy Asdigian, Jul 05, 2014
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    • "It is possible that intense and repeated sunlight exposure in childhood may increase the number of small naevi as total naevus counts are higher in Australia compared to the UK but it is likely that small lentigines are also miscounted as naevi on sun exposed sites [6]. Males also show consistently higher number of naevi than females and this is also seen in different parts of the world irrespective of sun exposure [8] [9]. The types of naevi also vary greatly according to body sites as intradermal naevi which are mature lesions with a low risk of transformation into melanoma are common on the face for example but are more rarely seen on the limbs for examples. "
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    • "Naevus density was highest on the face, neck and lateral forearms and total number of sunburns was associated with total naevus prevalence. Site-specific sunburns were significantly associated with naevus prevalence on the back (P = 0.03 for three or more sunburns) but not on the face, arms or legs (Dodd et al., 2007). Non-Hispanic white boys had significantly more naevi than did girls from 6 years of age, and this difference was due to more small naevi and naevi on chronically exposed body sites (Crane et al., 2009). "
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