Tanning bed exposure increases the risk of malignant melanoma

Abstract
Epidemiologic studies have associated tanning bed exposure and cutaneous melanoma. The relationship between the extent of tanning bed exposure and the risk of melanoma has not been elucidated in detail. Surveys assessing the extent of tanning bed exposure and the history of skin cancer, including malignant melanoma, were collected from academic dermatology clinic patients (n = 1518). Of these, 551 (36.3%) completed all components of the survey. The available medical records, including pathology reports (n = 501; 33%), were reviewed to confirm cases of skin cancer. Data on potential confounding factors, including indoor vs. outdoor occupation and leisure activities, Fitzpatrick skin type, history of blistering sunburn, use of sunscreen and sun protective clothing, history of phototherapy, and level of education, were assessed and compared. Of the patients surveyed, 487 (32.1%) reported tanning bed exposure. Women aged 45 years or younger accounted for about 60% of all tanning bed users. Seventy-nine cases of malignant melanoma were reported, 22 in women aged 45 years or younger. In the entire cohort, the "ever-use" of tanning beds was found to be a significant risk factor for the development of melanoma [P < 0.05; odds ratio (OR), 1.64; 95% confidence interval (95% CI), 1.01-2.67]. The risk was greater in women aged 45 years or younger (P < 0.05; OR, 3.22; 95% CI, 1.01-11.46). Patients with a history of melanoma were significantly more likely to report tanning bed sessions exceeding 20 min (P < 0.01; OR, 3.18; 95% CI, 1.48-6.82); this association was even stronger for women aged 45 years or younger (OR, 4.12; 95% CI, 1.41-12.02). The study was subject to recall bias, included only patients at a midwestern academic practice, and had a relatively low response rate. Exposure to tanning beds increases the risk of malignant melanoma, especially in women aged 45 years or younger. These findings reinforce the hazards of tanning bed exposure.