Reassessing the incidence of uveal melanoma in Germany: Insights from current cancer registry data

BACKGROUND: Uveal melanoma (UM), the most common adult primary intraocular malignancy, has its highest frequency in Europe. Because of the current diagnostic and therapeutic practices, calculating UM incidence can be error prone. Using cancer registry data, the aim here was to estimate UM incidence in Germany and North Rhine-Westphalia (NRW), its largest federal state. METHODS: All UM cases from the German Centre for Cancer Registry Data (RKI) in 2019-2021 were analyzed. Data were compared to the 2019-2022 data of NRW's cancer registry. We calculated crude incidence and age-standardized rates (ASR) using the 2013 European standard population. RESULTS: Overall, 2047 German and 830 NRW UM cases were included. In both datasets, the mean age at diagnosis was 65 years; men and women were equally affected. Ciliary body and iris melanomas represented 11-13% of total cases. In Germany (RKI dataset), ASR was 7.4 per million person-years (pyrs). Highest ASR was in the North (Schleswig-Holstein: 16.6 per million pyrs), followed by North-Eastern federal states (ASR: 11-13 per million pyrs in Brandenburg, Berlin, Saxony-Anhalt, Mecklenburg-Western Pomerania), and ASR was 4-8 per million pyrs in the remaining federal states. ASR in NRW was 6.2 (RKI dataset) but 10.6 per million pyrs using the state's cancer registry data. CONCLUSION: Determining UM incidence in Germany remains challenging. High incidence variations between both datasets and German federal states point to a probable incompleteness of the RKI UM-dataset. Incidence is likely higher than previously assumed, but similar to rates observed in Northern Europe (around 10-12 per million pyrs).