Vacations to Waterside Locations Result in Nevus Development in Colorado Children

Abstract

Nevi are a main risk factor for malignant melanoma, and most nevi develop in childhood. This study examined the relationship between vacations and nevi in 681 White children born in 1998 who were lifetime residents of Colorado. Vacation histories were assessed through telephone interviews of parents, whereas nevus and phenotypic characteristics were assessed through skin exams at age 7. Multiple linear and logistic regression were used to assess the influence of vacations on counts of nevi <2 mm in size and the presence of any nevi z2 mm after controlling for other variables. Each waterside vacation z1 year before the exam at age 7 was found to be associated with a 5% increase in nevi <2 mm. Waterside vacations <1 year before the skin exam were not related to nevus count (<2 mm); regardless of timeframe, waterside vacations were not related to the presence of nevi z2 mm. UV dose received on waterside vacations, number of days spent on waterside vacations, and nonwaterside vacations were not significantly related to nevi <2 or z2 mm. These results suggest that there is a lag of at least 1 year in the development of new nevi after vacation sun exposure. It appears that a threshold dose of UV exposure is received quickly on each waterside vacation. Parents of young children should exercise caution in selection of vacation locations to reduce melanoma risk. (Cancer Epidemiol Biomarkers Prev 2009;18(2):454 -63)

Tanning and Increased Nevus Development in Very-Light-Skinned Children Without Red Hair

“…It is also possible that intermittent intense UV exposure (rather than routine daily exposure) is required for nevus development, as has been suggested by Autier and colleagues 48. Numerous studies have noted a relationship between vacation sun exposure and nevus development, including an analysis of our full cohort at age 6 years,14–16,47–49 but such a relationship was not detected in this subgroup of light-skinned 8-year-olds. Likewise, sunburns were found to be related to nevus development in previous studies, including our full cohort,12,13,15,16,18,23,48 but this relationship was not found in the present analysis.…”

“…Vacation sun exposure, which has been reported to be related to nevus development in several previous studies, 14–16,47–49 was assessed in annual interviews (2004–2006) by inquiring about any vacations to sunny locations, including the location, season, and length of trip (in days). Using methods established previously in this cohort,47 vacation locations were classified as waterside if they had a body of water and were known to be associated with recreational activities that would lead the participant to get significant sun exposure (eg, surfing, water skiing, boating).…”

“…Using methods established previously in this cohort,47 vacation locations were classified as waterside if they had a body of water and were known to be associated with recreational activities that would lead the participant to get significant sun exposure (eg, surfing, water skiing, boating). Due to seasonal temperatures, within the United States, only Hawaii and locations below latitude 27.5°N qualified as waterside year round.…”

“…Other water destinations in the United States were deemed waterside only during the summer months of June, July, and August. Under the expectation that a time lag of at least 1 year is necessary for intense sun exposure to stimulate nevus development, vacations over each child’s life were used to create 2 variables: total number of waterside vacations more than 1 year prior to summer 2006 and total number of waterside vacations 1 year or less prior to summer 2006 47,50…”

Developing Healthy Sun Habits for Life

“…Fewer parents, however, are probably aware of the direct relationship between vacation sun exposure and nevi development. 4 An obvious recommendation that emerges from both facts would be the avoidance of intermittent intense UV exposure during beach or ski vacations.…”