Outdoor workers at high risk for developing BCC
MedWire News: Outdoor workers have a significantly high risk for developing basal cell carcinoma (BCC), show findings from a meta-analysis and systematic review.
Epidemiological evidence suggests that occupationally ultraviolet (UV)-exposed workers have a 40% increased risk for developing BCCs compared with non-exposed workers, but the risk may be understimatd due to poor study design.
"Our findings are highly relevant as BCC is the most common cancer in White individuals with rapidly increasing incidence rates incurring huge costs for society," comment Andrea Bauer (Technical University Dresden, Germany) and colleagues.
The researchers performed a systematic literature review of five cohort studies and 19 case-control epidemiological studies providing data on occupational UV exposure and BCC occurrence. A random-effects meta-analysis and sensitivity analysis on study-specific co-variates was then performed.
In total, 15 studies were performed in Europe, three in North America, four in Australia, one in South America, and one study in both Europe and South America.
A significant positive relationship between occupational UV exposure and risk for BCC was found in 11 studies, with odds ratios (ORs) between 1.3 and 4.7.
Conversely, six studies found a nonsignificant increased risk, while two studies did not find any effect of occupational UV exposure on BCC risk. Five studies showed a nonsignificant risk reduction for workers in outdoor occupations with ORs between 0.74 and 0.90.
The authors suggest that lack of accurate classification of occupations and contamination of UV-exposed groups by less UV-exposed employees, as well as contamination of controls by employees exposed to various amounts of solar radiation probably weakened or even eliminated the associations.
Meta-analysis findings from 23 of the 24 included studies found a 1.43-fold increased risk for BCC among outdoor workers. Studies that adjusted for gender and individual non-occupational UV exposure showed a significantly stronger association of occupational UV exposure and BCC risk. No such influence was found in studies adjusting for skin type/UV sensitivity or family history of cancer.
Data source (general population, registry versus hospital patients) and method of occupational UV exposure did not change the association between occupational UV exposure and BCC risk.
Meta-regression analysis on the influence of each single study revealed that none of the included studies significantly influenced the study findings. Furthermore, a significant inverse relationship was found between occupational UV radiation exposure and BCC risk with latitude.
"Much larger well-designed case-control and/or cohort studies are now needed to establish the real impact of occupational UV irradiation on BCC risk in outdoor work to inform occupational safety representatives about the true extent of risk in exposed workers and stimulate the introduction of adequate prevention strategies for this easily preventable tumor," conclude the authors in the British Journal of Dermatology.
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By Ingrid Grasmo