Is Sunlight a Predisposing Factor for Triple Negative BreastCancer in Turkey?

Intraductıon: There is known to be a relationship between vitamin D level and more aggresive breast cancersubtypes, especially triple-negative breast cancer (TNBC). It was reported that sunlight exposure has an effecton the prognosis of patients with cancer, possibly related to the conversion of vitamin D to its active form withsunlight. We aimed to evaluate the effect of sunlight exposure on patients with TNBC. Materials-
Methods: Atotal of 1,167 patients with breast cancer from two different regions of Turkey (Antalya and Kayseri, regionshaving different climate and sunlight exposure intensity over the year) were analysed retrospectively. The ratioof patients with TNBC was identified in those two regions.
Results: The ratio of patients with TNBC was 8% and12% for Kayseri and Antalya regions, respectively, and this difference between the two groups was statisticallysignificant (p=0.021). Discussion: Sunlight exposure may be associated with more prevalent TNBC. This findingshould be investigated with a prospective study.