title: Prolonged prevention of squamous cell carcinoma of the skin by regular sunscreen use.
abstract: Half of all cancers in the United States are skin cancers. We have previously shown in a 4.5-year randomized controlled trial in an Australian community that squamous cell carcinomas (SCC) but not basal cell carcinomas (BCC) can be prevented by regular sunscreen application to the head, neck, hands, and forearms. Since cessation of the trial, we have followed participants for a further 8 years to evaluate possible latency of preventive effect on BCCs and SCCs. After prolonged follow-up, BCC tumor rates tended to decrease but not significantly in people formerly randomized to daily sunscreen use compared with those not applying sunscreen daily. By contrast, corresponding SCC tumor rates were significantly decreased by almost 40% during the entire follow-up period (rate ratio, 0.62; 95% confidence interval, 0.38-0.99). Regular application of sunscreen has prolonged preventive effects on SCC but with no clear benefit in reducing BCC.
authors.affiliation: School of Population Health, University of Queensland, Brisbane, Queensland 4029, Australia.
authors.forename: Jolieke C
authors.initials: JC
authors.lastname: van der Pols
authors.forename: Gail M
authors.initials: GM
authors.lastname: Williams
authors.forename: Nirmala
authors.initials: N
authors.lastname: Pandeya
authors.forename: Valerie
authors.initials: V
authors.lastname: Logan
authors.forename: Adèle C
authors.initials: AC
authors.lastname: Green
mesh_terms: D001315:Australia / Q000453:epidemiology; D002280:Basal Cell Carcinoma / Q000453:epidemiology / Q000517:prevention & control*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000517:prevention & control*; D005500:Follow-Up Studies; D006801:Humans; D012878:Skin Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D013473:Sunscreening Agents / Q000627:therapeutic use*
chemical_list: D013473:Sunscreening Agents