RESUMO
INTRODUCTION AND OBJECTIVES: Patients with melanoma appear to take extreme sun-protection measures, which could influence 25-hydroxyvitamin D [25(OH)D] levels. The aim of this study was to measure 25(OH)D levels in patients with cutaneous melanoma and identify factors associated with inadequate levels. MATERIAL AND METHODS: Over a period of 1 year, we prospectively measured serum 25(OH)D in patients with cutaneous melanoma and used logistic regression analysis to identify environmental, phenotypic, and genotypic factors that were associated with insufficient and deficient levels. RESULTS: Of 215 patients analyzed, 8.8% had deficient 25(OH)D levels (<10ng/mL) and just 24.7% had normal levels. Insufficient levels (<30ng/mL) were associated with obesity (odds ratio [OR], 4.2; 95% confidence interval [CI], 1.3-13.3) and blood sampling in autumn/winter (OR, 2.1; 95% CI, 1.1-4). Deficient levels (<10ng/mL) were associated with obesity (OR, 7.1; 95% CI, 1.1-46.9), blood sampling in autumn/winter (OR, 9.0; 95% CI, 1.7-47.0), absence of freckles (OR, 5.4; 95% CI, 1.2-23.4), and, with marginal significance, the presence of fewer than 2 nonsynonymous melanocortin-1 receptor (MC1R) polymorphisms (OR, 5.0; 95% CI, 0.9-28.9). LIMITATIONS: Some factors related to 25(OH)D levels, such as food, were not included in the analyses. CONCLUSIONS: 25(OH)D levels should be monitored in patients with melanoma and the need for oral supplements should be contemplated where appropriate.