Abstract 2209: Tattooing and risk of melanoma: A population-based case-control study in Utah
Authors: McCarty Rachel D. , Trabert Britton , Millar Morgan M. , Kriebel David , Grieshober Laurie , Barnard Mollie E. , Collin Lindsay J. , Lawson-Michod Katherine A. , Gilreath Jeffrey A. , Grossman Douglas , Hyngstrom John , Shami Paul J. , Doherty Jennifer A. 
Published: March 2024

Background: Carcinogens have been observed in many tattoo inks which can form new carcinogenic compounds when exposed to ultraviolet radiation and can accumulate in the lymph nodes and other organs. Tattooing can result in short- and long-term inflammatory and immune responses. At least 38 cases of melanoma have been reported in tattoos. The incidence of melanoma in Utah is the highest in the U.S., and potentially modifiable risk factors are of public health interest. In this study, we evaluated associations between tattooing and melanoma risk.

Methods: We utilized a population-based case-control study of 514 incident in situ (284 men and 230 women) and 534 invasive (285 men and 249 women) melanoma cases diagnosed in Utah between 2020-2021. Controls (n=5,240) were selected from respondents to the Utah Behavioral Risk Factor Surveillance System (BRFSS) survey and frequency matched to cases in a 5:1 ratio on sex, age, race, and ethnicity. We fit logistic regression models to compute odds ratios (ORs) and 95% confidence intervals (CIs) associating ever tattooing with in situ and invasive melanoma risk, adjusting for age, education level, race, and ethnicity, separately for women and men. We then fit logistic models stratified by education level (&lt; four-year college degree/four-year college degree or more) and models stratified by age (&lt; 50 years/50+ years), separately for women and men.

Results: Among men, the prevalence of tattooing was 7% for both in situ and invasive cases, and 11% for controls. Among women, tattooing prevalence was 20% for in situ cases, 15% for invasive cases, and 18% for controls. Ever tattooing was associated with decreased invasive melanoma risk among men (OR=0.62 [95% CI: 0.37-1.02]), particularly among those who had less than a four-year college degree (0.52 [0.28-0.99]), and among ages 50+ (0.36 [0.16-0.84]). Among men, the OR for ever tattooing and in situ melanoma was in the same direction as invasive melanoma, but the estimate was statistically imprecise (0.73 [0.45-1.19]). Among women, we did not observe an association between ever tattooing and invasive melanoma (0.83 [0.56-1.20]), while the association between ever tattooing and in situ melanoma was statistically imprecise (1.25 [0.87-1.80]). However, ever tattooing was associated with a nearly two-fold increased risk of in situ melanoma among women with a four-year college degree (1.98 [1.21-3.26]), but not for those without a college degree (0.89 [0.52-1.50]).

Conclusion: These findings do not suggest that there is an association between tattooing and melanoma. Associations between tattooing and health-seeking behaviors, which may vary by sex and other demographic factors, may influence associations with melanoma diagnosis, particularly for in situ melanoma. This study is the first step in investigating whether reported cases of melanoma arising in tattoos are coincidental or whether tattoos may be associated with an increased risk of melanoma.

Citation Format: Rachel D. McCarty, Britton Trabert, Morgan M. Millar, David Kriebel, Laurie Grieshober, Mollie E. Barnard, Lindsay J. Collin, Katherine A. Lawson-Michod, Jeffrey A. Gilreath, Douglas Grossman, John Hyngstrom, Paul J. Shami, Jennifer A. Doherty. Tattooing and risk of melanoma: A population-based case-control study in Utah [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2209.