Severe Sunburns and Sunbed Use Risk with Cutaneous Melanoma: A Case-Control Study in Lithuania

Background and Objectives: To our knowledge, this is the first case-control study conducted in the Baltic countries that identified CM risk factors focusing on the investigated subjects' phenotypic traits, severe sunburns, sunscreen and tanning bed use. Materials and Methods: This study analyses 180 subjects with CM (case group) and 182 randomly selected controls. All participants completed surveys about sun exposure habits and skin phototype (I-IV) according to the Fitzpatrick scale. Skin, eye, and hair colour, number of freckles, and melanocytic nevi greater than 2 mm in diameter (MN > 2 mm) on sites with maximal, intermittent, and minimal sun exposure were examined. Results: We determined five risk factors that significantly increased the odds ratio of CM (OR; 95% confidence interval): tanning bed use compared to non-use (6.46; 1.89-22.96), lack of sunscreen use compared to regular use (7.41; 2.88-19.09), and fair skin compared to medium and olive skin (2.06; 1.03-4.09). The probability of CM also increased with each instance of severe sunburn (2.57; 1.96-3.38) and with each additional MN > 2 mm in sun-exposed areas (1.05; 1.03-1.07). Conclusions: The results of this case-control study offer novel insights into modifiable risk factors for CM, highlighting potential targets for primary prevention strategies in the Baltic countries' population, with dominant fair phenotypic traits of skin, eye, and hair colour.