[Potential of Using Vitamin D as an Adjuvant Treatment of Malignant Melanoma].

The incidence of malignant melanoma worldwide continues to grow despite the enormous advances in topical and systemic therapy. This increase is recorded regularly even in countries where, as a result of public health campaigns, dermatological examination and subsequent treatment have become more frequent. However, there have been reports of a stable or even decreasing mortality rate that seem to contradict the objective increase in its incidence. The well-known risk factors for malignant melanoma include sunburns and occasional sunbathing, whereas regular sunbathing is associated with a lower incidence. Besides DNA damage, exposure to the sun also results in the synthesis of vitamin D (cholecalciferol) in the skin, which contributes to over 90% of circulating Calcidiol (25 (OH) D) in serum. Current cultural norms (dressing, working indoors, avoiding sun exposure, and dietary choices) affect the serum vitamin D level, resulting in severely low serum levels of vitamin D in some sectors of todays society. Emerging data suggests that mild, unprotected exposure to UV radiation or dietary supplementation with oral vitamin D can reduce cancer mortality. Supplementation with vitamin D or alternatively UV exposure may be regarded as an adjuvant for the treatment of many types of tumors (e.g. tumors of the colon, prostate, and breast). The effect of vitamin D on malignant melanoma may be due to its non-calcemic systemic effects. Additionally, vitamin D may have more pronounced effects locally in the skin because of the unique ability of keratinocytes to synthesize the active form of vitamin D.Key words: malignant melanoma - vitamin D - adjuvant treatment therapy - clinical oncology The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 7. 10. 2016Accepted: 26. 7. 2017.