Reduced melanoma after regular sunscreen use: randomized trial follow-up
Tuesday December 7, 2010
“For the first time, researchers have shown that daily sunscreen use can prevent melanoma in adults”, according to a Queensland Institute of Medical Research media release featuring a recent study published in the Journal of Clinical Oncology.
As outlined in the study abstract, the effect of regular sunscreen on melanoma is highly controversial. The purpose of the Queensland study therefore was to evaluate whether long-term application of sunscreen decreases the risk of cutaneous melanoma.
In 1992, 1,621 randomly selected residents of Nambour, Queensland, age 25 to 75 years, were randomly assigned to daily or discretionary sunscreen application to head and arms in combination with 30 mg beta carotene or placebo supplements until 1996. Participants were observed until 2006 with questionnaires and/or through pathology laboratories and the cancer registry to ascertain primary melanoma occurrence.
According to the study abstract, ten years after trial cessation, 11 new primary melanomas had been identified in the daily sunscreen group, and 22 had been identified in the discretionary group, which represented a reduction of the observed rate in those randomly assigned to daily sunscreen use (hazard ratio [HR], 0.50; 95% CI, 0.24 to 1.02; P = .051). The reduction in invasive melanomas was substantial (n = in active v 11 in control group; HR, 0.27; 95% CI, 0.08 to 0.97) compared with that for preinvasive melanomas (HR, 0.73; 95% CI, 0.29 to 1.81).
The authors conclude that melanoma may be preventable by regular sunscreen use in adults.
Source: Green AC, Williams GM, Logan V, Strutton, GM. Reduced Melanoma After Regular Sunscreen Use: Randomized Trial Follow-Up. Journal of Clinical Oncology. Published online before print December 6, 2010, doi: 10.1200/JCO.2010.28.7078
Abstract: http://jco.ascopubs.org/content/early/2010/12/02/JCO.2010.28.7078.abstract
Media release:http://www.qimr.edu.au/page/News__Events/Media_Centre/Media_Releases/Sunscreen_can_prevent_melanoma/
An editorial in the same issue (Sunscreen and Melanoma: What Is the Evidence?)
concludes that “sunscreen use alone will likely not reduce the incidence of skin cancer, which is an increasingly widespread and serious public health problem in the United States and globally. In addition to sunscreen use, excess exposure to ultraviolet rays should be avoided, clothing should be used to shield skin from the sun, and sun-safe environments should be used for outdoor recreation. In addition, sunscreen use should be paired with regular self-examination of the skin. The question of its efficacy with respect to melanoma prevention should no longer deter scientists or clinicians from recommending sunscreen use.”
Editorial: http://jco.ascopubs.org/content/early/2010/12/02/JCO.2010.31.7529.full.pdf+html
