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

## TL;DR

This study found that Merkel cell carcinoma incidence in Austria increased over time and was higher in regions with more UV exposure, suggesting UV radiation may contribute to the disease.

## Contribution

The study is one of the first to analyze MCC incidence in Austria and link it to regional UV radiation levels.

## Key findings

- Merkel cell carcinoma incidence increased from 0.013 to 0.43 per 100,000 between 1990 and 2018.
- Higher UV radiation levels in western Austria correlated with higher MCC incidence rates.
- Elderly patients showed a significant increase in MCC cases.

## Abstract

Merkel cell carcinoma (MCC) is a rare but aggressive skin cancer. This study analyzed Austrian cancer registry data between 1990 and 2018 and investigated a possible link between MCC incidence and ultraviolet (UV) radiation. We observed a strong increase in MCC cases, with higher incidence rates in western Austria, where UV radiation levels are also higher. Although MCC is uncommon, its incidence is rising, especially among elderly patients. These findings suggest that cumulative UV exposure contributes to MCC development. Raising awareness among physicians and the public may help to improve early diagnosis and patient outcomes.

Background: The purpose of this study was to report on (i) patients’ demographics and (ii) Austrian UV data, and (iii) to examine a possible association between UV exposure and the onset of disease in Austria between 1990 and 2018. Methods: We included all patients diagnosed with MCC and their clinical and demographic data to compare with UV radiation. Results: A total of 538 cases were identified, and the incidence (per 100,000/y) increased from 0.013 to 0.43. The MCC incidence was significantly higher in West Austria (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 with the MCC incidence. Conclusions: The incidence of MCC increased significantly, and higher UV radiation levels in western Austria compared to the east were associated with a correspondingly higher MCC incidence, suggesting a contributing role of UV radiation in general.