Sex differences in numbers of nevi on body sites of young European children: implications for the etiology of cutaneous melanoma.
ABSTRACT Since 1950, the greatest increase in cutaneous melanoma incidence in fair-skinned males took place on the trunk and on the head and neck, whereas in females, it took place on the limbs, mainly on the lower limbs. We examined the influence of sex on numbers and size of nevi on different body sites in white European schoolchildren.
Information about each holiday period since birth to interview was recorded from parents of six hundred twenty-eight 6- to 7-year-old children in four European cities (Brussels (Belgium), Bochum (Germany), Lyons (France), and Rome (Italy)). Number and anatomic location of small (2-4.9 mm) and large (>/=5 mm) nevi and individual susceptibility to sunlight were independently assessed.
After adjustment for host characteristics, sun exposure, and sun protection habits, males had 7% [95% confidence interval (95% CI), -7 to 19] more small nevi than females. However, compared to females, numbers of small nevi were increased by 17% (95% CI, 1-31) on the head and neck and by 16% (95% CI, 2-27) on the trunk and shoulders. In contrast, in males, the number of small nevi on upper limbs was decreased by -5% (95% CI, -26 to 13), and on lower limbs by -8% (95% CI, -34 to 13). The number of large nevi was 6% higher in males than in females (95% CI, -26 to 30).
The sex differences in small nevus distribution in schoolchildren reflect the sex differences in the anatomic distribution of melanoma in adults. Sex differences in sun exposure behaviors, dressing, and clothing would just add their effects to the sex-dependent inherited propensity to develop nevi on a given body site. These results reinforce the hypothesis by which childhood would be a decisive period for the occurrence of sun-induced biological events implicated in the genesis of cutaneous melanoma.
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ABSTRACT: The incidence of melanoma is rising steadily around the world, with varying mortality trends among different populations. Particularly, incidence rates among young adults, below age 40 years, have increased dramatically in the past decades. In young adults, the gender predominance is switched, with the highest incidence occurring in young women. Multiple risk factors are associated with higher risk of developing melanoma. Intermittent sunlight exposure and use of tanning beds early in life increase significantly the risk of melanoma. The prevalence of tanning bed use among young women and adolescents is increasing continuously. This trend may be associated with the increase in melanoma incidence among young women. Efforts to implement new active interventions that will increase public awareness of melanoma and the risks of tanning bed use are crucial; regulations on tanning bed use especially among those underage should be implemented.Expert Review of Dermatology 01/2014; 8(6). DOI:10.1586/17469872.2013.844465
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ABSTRACT: The objective was to estimate the prevalence of melanocytic nevi (MN) in children and to determine their dermoscopic characteristics and relationship with anatomic location and environmental and constitutional factors. The population was a randomly selected sample of 144 children who attended primary schools in Naples, Italy. Before physical examination of the children, standardized interviews were conducted with their parents. Follow-up interviews of both the children and parents were conducted 1 year later. Photographic and dermoscopic images were obtained. Boys had more MN than girls; 465 MN (55.6%) were observed in boys and 371 (44.4%) in girls (p < 0.05). The trunk and neck were the most common locations of MN (p < 0.001). The main dermoscopic feature of all MN observed was a globular pattern (p < 0.001). A significant correlation between duration of sunbathing and MN counts was revealed (p < 0.05). At 1-year follow-up, 118 new MN were identified in 66 children. The trunk and neck areas were the most common regions involved in the appearance of new MN (n = 68, 57.6% of all new MN, p < 0.001). The new MN count was significantly higher in children who reported more sunbathing (p < 0.001). Changes in the dermoscopic pattern were observed in 45 persistent MN, demonstrating more MN with a reticular-globular pattern, especially on the trunk, neck, and upper extremities (p < 0.001). MN development in early life is the result of complicated relationships between nevus evolution, anatomic location, and environmental and constitutional factors.Pediatric Dermatology 05/2013; 31(1). DOI:10.1111/pde.12119 · 1.52 Impact Factor