(HealthDay)—Some people with melanoma aren't cautious about sun exposure, a small new study suggests, even though ultraviolet (UV) radiation from the sun is a major cause of skin cancer.
Researchers looked at 20 patients with malignant melanoma—the most deadly type of skin cancer—and a comparison group of 20 people without melanoma, all of whom carried portable UV-dose-detection devices and kept sun exposure diaries to measure their exposure to UV radiation.
Patients' overall daily UV radiation exposure rose 25 percent from the first to second summer after their melanoma diagnosis, and increased 33 percent from the first to the third summer, found the study published online Oct. 2 in the journal JAMA Dermatology.
The patients' UV exposure was also higher on vacation days and when they traveled to other countries, said Dr. Luise Winkel Idorn, of Bispebjerg Hospital and the University of Copenhagen in Denmark, and colleagues.
In comparison, people without melanoma had steady levels of UV radiation exposure, according to a journal news release.
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The U.S. National Cancer Institute has more about melanoma and other skin cancers.