Abstract
Background: Intensive scientific debate is ongoing about whether moderate solarium use increases melanoma risk. The authors of some recent publications demand the debate be closed and propose “actions against solarium use for skin cancer prevention” because new studies have convincingly demonstrated causality. This minireview aims to investigate whether those demands are sufficiently supported by present scientific knowledge and comply with the principles of evidence-based medicine. Materials and Methods: We performed a systematic literature search (through June 2019; PubMed, ISI Web of Science) to identify publications investigating how solarium use affects melanoma risk. Results: We found no studies that demonstrate a causal relationship between moderate solarium use and melanoma risk. Results of cohort and case–control studies published to date, including recent investigations, do not prove causality, and randomized controlled trials providing unequivocal proof are still lacking. Moreover, the overall quality of observational studies is low as a result of severe limitations (including unobserved or unrecorded confounding), possibly leading to bias. We also disagree with recent claims that Hill's criteria for the epidemiological evidence of a causal relationship between a potential causal factor and an observed effect are fulfilled in regard to the conclusion that moderate solarium use per se would increase melanoma risk Conclusion: Current scientific knowledge does not demonstrate a causal relationship between moderate solarium use and melanoma risk. Therefore, the debate is not closed.
Footnotes
Authors' Contributions
Literature search: JR. Data analysis: JR, PL, WM, SP, MH, WG, FDG. Article preparation: JR, PL, WM, SP, MH, WG, FDG.
This article is freely accessible online.
Conflicts of Interest
William B. Grant received funding from Canadian, European, and U.S. indoor tanning companies and organizations during the period 2005 to 2014. Saarland University (with JR being a responsible project coordinator) received research funding from the Jörg Wolff foundation.
- Received November 13, 2019.
- Revision received November 29, 2019.
- Accepted December 3, 2019.
- Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved