The ability of the GENESIS-UV metric to reflect the positive dose-response relationship between cumulative occupational UV exposure and squamous cell carcinoma of the skin

The newly developed GENESIS-UV metric is based on occupational UV exposure measurements in about 1,000 outdoor-workers (covering 250 different occupational settings). The GENESIS-UV metric calculates occupational exposure values for the standard erythema dose (SED) that differ substantially from those produced by the “Wittlich metric” which applies multiple correction factors to a fixed SED reference value of 300 SED per year. This Wittlich metric has served as the basis for calculating occupational UV exposure of occupational disease No. 5103 (“squamous cell carcinoma or multiple actinic keratoses caused by natural UV radiation”) in Germany since 2015. In a large case-control study (“FB181”, 632 cases and 632 individually matched control subjects), a positive dose-response relationship between UV exposure estimated using the “Wittlich metric” and squamous cell carcinoma (SCC) of the skin could be derived. This study aimed to investigate whether the increased SCC risk for high occupational UV exposure found in the FB181 study can be reflected with the new GENESIS-UV metric. Based on propensity-score matched data from the FB181 study, odds ratios (OR) with 95% confidence intervals (CI) for categorized occupational UV exposure were calculated using conditional logistic regression analysis. The analyses were adjusted for age, sex, skin phototype, and non-occupational UV exposure. To examine the suitability of the GENESIS-UV metric, exposure was calculated using both the Wittlich metric and the GENESIS-UV metric. The goodness of fit was assessed using the Akaike information criterion (AIC). When applying the Wittlich metric, individuals with high cumulative occupational UV exposure (≥ 90th percentile) show a statistically significant increase in OR of 1.95 (95% CI 1.19–3.18). When applying the GENESIS-UV metric, the corresponding OR for reaching or exceeding the 90th percentile is 2.23 (95% CI 1.36–3.65). The goodness of fit of the GENESIS-UV metric is substantially better than that of the Wittlich metric (AIC of 748.0 versus 758.6). Applying the newly developed GENESIS-UV metric, we were able to confirm the positive dose-response relationship between occupational UV exposure and squamous cell carcinoma of the skin in this sensitivity analysis of the FB181 case-control study. The GENESIS-UV metric proves to be suitable for determining occupational UV exposure.