Scientists researching children in Colorado, USA, found that holidays at the beach or other waterside resorts could increase children’s future risk of getting melanoma, the most dangerous form of skin cancer.
The study was the work of lead author Dr Lori Crane, who is chair of the Department of Community and Behavioral Health at the Colorado School of Public Health in the University of Colorado Denver, and colleagues, and was published in the 3 February online issue of Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research.
The number of “nevi” or moles on our bodies is a risk factor for malignant melanoma, the deadliest form of skin cancer, and most of them develop in childhood. More than 62,000 Americans are diagnosed with malignant melanoma and over 8,000 die of it every year. Rates of malignant melanoma have shot up in recent decades.
Studying 7-year old children, Crane and colleagues found that having vacations at the shore led to at least 5 per cent increase in the number of nevi or moles on their bodies.
Although they studied children living in Colorado, the researchers said their findings were relevant to all children and that parents of young children should be very careful when they take them on holiday to places where they will be exposed to the sun. This is especially the case at waterside locations where kids are likely to spend many hours at a time in bathing costumes with their bodies uncovered.
Crane recommended that parents and carers:
“Keep the kids involved in indoor activities from 10:00 am to 4:00 pm to decrease risk, or if they are to be outside, that they wear shirts with sleeves.”
For the study, the researchers examined 681 white children who were born in 1998 and had lived in Colorado all their lives. They asked parents about the type and place of holidays and the children underwent skin examinations to assess the development of nevi.
The results showed that:
- For each waterside holiday the children had had at least one year prior to their exam, there was a 5 per cent increase in the number of nevi, or skin moles, less than 2 mm in size (most likely to be the new nevi).
- There was no association between waterside holidays and nevi larger than 2 mm.
- Daily exposure to the sun at home did not seem to be related to the number of nevi, only waterside vacations.
- UV doses received and number of days spent on waterside vacations, and non-waterside vacations, were not significantly linked to nevi of any size.
- There appeared to be a lag of at least one year in the development of new nevi after vacation sun exposure.
- Children from higher income families were also more likely to have higher numbers of nevi.
- Young boys had a 19 per cent higher risk than young girls for nevi development.
Crane and colleagues said that perhaps young boys are more likely to stay outside than young girls, and that children from higher income families were more likely to have more waterside holidays.
They concluded that:
“Parents of young children should exercise caution in selection of vacation locations to reduce melanoma risk.”
Crane said:
“Daily sun exposure at home did not seem to be related to the number of moles, while waterside vacations were. Vacations may impart some unique risk for melanoma.”
“Vacations to Waterside Locations Result in Nevus Development in Colorado Children.”
Kelly J. Pettijohn, Nancy L. Asdigian, Jenny Aalborg, Joseph G. Morelli, Stefan T. Mokrohisky, Robert P. Dellavalle, and Lori A. Crane.
Cancer Epidemiol Biomarkers Prev first published on February 3, 2009.
doi:10.1158/1055-9965.EPI-08-0634
Sources: Journal abstract, American Association for Cancer Research.
Written by: Catharine Paddock, PhD