Sunburn's Skin Cancer and Melanoma Risk Varies by Age of Exposure

June 13, 2014
Christina Izzo

A new study has shown that the risk of developing melanoma was more closely related to sun exposure in early life than in adulthood in young Caucasian women.

Abrar A. Qureshi, MD, MPH

A new study has shown that the risk of developing melanoma was more closely related to sun exposure in early life than in adulthood in young Caucasian women.

The longitudinal study, published in Cancer Epidemiology, Biomarkers & Prevention, found that those who had ≥5 blistering sunburns between age 15 and 20 had a 68% increased risk for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin and an 80% increased risk of melanoma.

“Our results suggest that sun exposures in both early life and adulthood were predictive of non-melanoma skin cancers, whereas melanoma risk was predominantly associated with sun exposure in early life in a cohort of young women,” Abrar A. Qureshi, MD, MPH, professor and chair of the Department of Dermatology at Warren Alpert Medical School of the Brown University and Rhode Island Hospital, said in a press release.

However, those who were exposed to the highest amounts of cumulative ultraviolet (UV) radiation in adulthood had no increased risk for melanoma, but had a 2.35-fold and 2.53-fold increased risk for developing BCC and SCC of the skin.

“Pattern of sun exposure was not uniformly associated with the risk for all three main skin cancers we see in the United States, suggesting that there are some differences in the pathophysiology of these skin cancers,” said Qureshi. “An individual’s risk of developing skin cancer depends on both host and environmental risk factors. Persons with high host-risk traits, such as red hair color, higher number of moles, and high sunburn susceptibility, should pay more attention to avoid excessive sun exposure, especially early in life.”

The study followed over 100,000 Caucasian registered nurses from the Nurses’ Health Study II for about 20 years. At the time of registration, participants were between the ages of 25 and 42 and resided in 14 different states.

Of the study participants, 6955 were diagnosed with BCC, 880 were diagnosed with SCC of the skin, and 779 were diagnosed with melanoma. Of those with melanoma, 445 had invasive cancer.

At registration, the participants responded to a baseline questionnaire about their medical histories and potential risk factors for skin cancers, including number of moles on the legs, number of blistering sunburns between age 15 and 20, and family history of melanoma.

Health information and additional questions related to skin cancer risk, including updated family history, tanning bed use, smoking and alcohol consumption habits, and body mass index were collected every 2 years for about 20 years.

About 24% of the participants had experienced painful blisters as a child or adolescent, about 10% had more than five blistering sunburns between age 15 and 20, and about 24% had used tanning beds.

“Parents may need to be advised to pay more attention to protection from early-life sun exposure for their kids in order to reduce the likelihood of developing melanoma as they grow up,” said Qureshi. “Older individuals should also be cautious with their sun exposure, because cumulative sun exposure increases skin cancer risk as well.”

Wu S, Han J, Laden F, Qureshi AA. Long-term ultraviolet flux, other potential risk factors, and skin cancer risk: a cohort study. Cancer Epidemiol Biomarkers Prev. 2014;23(6):1080-1089.