The relationship between occupational sunlight exposure and non-melanoma skin cancer

© 2015 Stephanie Soo Hwei TanAims and Background: Australia has the highest incidence of skin cancer in the world and ultraviolet (UV) radiation exposure is the dominant environmental determinant of all major forms of skin cancer. Two recent systematic reviews and meta-analysis of the available epidemiological evidence clearly indicate that occupational ultraviolet radiation (UVR) exposure is a substantial risk factor for the development of non- melanoma skin cancer. This study is an initial attempt to investigate the role of occupational sunlight exposure in the development of non-melanoma skin cancer in men in Australia. Methods: A case-control study was conducted. One hundred cases were recruited from the Skin and Cancer Foundation Inc. Controls included 14 age- and gender-matched subjects nominated by the cases. A questionnaire was administered through face-to- face interviews to collect information on pigmentary and genetic characteristics, occupational and recreational exposure assessment, and time of first diagnosis of non- melanoma skin cancer, confirmed with histopathological diagnosis. Conditional logistic regression models were implemented. Subsequently, a one-way analysis of variance (ANOVA) was used to investigate the relationship of each risk factor with occupational sun exposure. Results: There was insufficient evidence to conclude that there was a relationship between occupational sun exposure and non-melanoma skin cancer, because of the small sample size of matched case-control pairs. As the results for the small sample size of the matched case-control group were not statistically significant, a one-way analysis of variance (ANOVA) was performed to compare the risk factors. Fitzpatrick Skin Type was the only risk factor that showed a statistically significantly different occupational exposure profile (with a P-value of 0.035) but even then the differences were minor and only between skin phototype 2 and 3. There were no significant relationships between occupation exposure and the other risk factors. Conclusion: Unfortunately, analysis of the small number of matched case-control pairs was not statistically significant and it was not possible to draw any conclusions regarding the role of occupational sunlight exposure in the development of non- melanoma skin cancer. We experienced unexpectedly high levels of reluctance from case subjects to propose control subjects to participate in the study, which impacted on data collection and subsequently the study results. It has been well established that solar UVR is a risk factor for skin cancer. Outdoor workers are potentially exposed to high levels of UVR. More epidemiological studies are needed to improve our understanding and awareness of skin cancer as well as aid the development of prevention strategies at workplaces to reduce outdoor workers’ exposure to UVR