Impact of UV Exposure and Incidence of Merkel Cell Carcinoma Between 1990 and 2018 in Austria

Background: To describe i) patients´ demographic, ii) Austrian UV-data and iii) to analyze a possible relationship between UV exposure and onset of disease in Austria between 1990 and 2018. Methods: We included all patients with MCC diagnosed and clinical and demographic data to compare to UV radiation. Results: A total of 538 cases were identified and the incidence (per 100.000/y) increased from 0.04 to 3.45. The MCC incidence was significantly higher in West- (mean incidence 0.269 ± 0.04) compared to East-Austria (0.180 ± 0.02 p=0.005). Notably, the mean and maximum UV radiation values were higher in the Western (p< 0.001) compared to the Eastern part of Austria. The sum (p=0.033; r: 0.503) and mean (p=0.019; r: 0.546) UV values correlated significantly to the MCC incidence. Conclusions: MCC incidence increased significantly and a higher UV radiation in West- compared to East-Austria that subsequently resulted in a higher MCC incidence could be determined.