How many melanomas might be prevented if more people applied sunscreen regularly?

Area of Science:

• Dermatology and Public Health
• Epidemiology
• Cancer Prevention

Background:

• Ultraviolet (UV) radiation is a primary cause of cutaneous melanoma.
• Sunscreen use is scientifically linked to preventing sunburn and protecting skin cells from UV-induced mutations.
• Epidemiological evidence supports regular sunscreen application as a melanoma prevention strategy.

Purpose of the Study:

• To quantify the potential impact fraction (PIF) of melanoma in the U.S.A. and Australia.
• To model various intervention scenarios aimed at increasing sunscreen usage.
• To estimate melanoma incidence reductions under different sunscreen use prevalence levels.

Main Methods:

• Calculated PIF, comparing observed melanoma cases to expected cases under counterfactual sunscreen use scenarios.
• Utilized published melanoma incidence projections (2012-2031) for the U.S. white population and Australia.
• Incorporated literature estimates for the protective effects of regular sunscreen use and sourced national survey data for sunscreen prevalence.

Main Results:

• A plausible public health intervention increasing sunscreen prevalence over 10 years could prevent an estimated 231,053 melanomas in the U.S. and 28,071 in Australia by 2031.
• Under a theoretical maximum sunscreen use model, nearly 797,000 melanomas could be prevented in the U.S. and 96,000 in Australia between 2012 and 2031.
• Sensitivity analysis indicated that more conservative PIF estimates result from using weaker effect estimates for sunscreen's protective benefits.

Conclusions:

• Interventions promoting increased sunscreen use can lead to moderate reductions in melanoma incidence.
• These reductions are contingent upon users not engaging in compensatory sun overexposure.
• High-incidence countries should actively monitor community-level sunscreen usage patterns.