Outdoor work and skin cancer incidence: a registry-based study in Bavaria

Occupational solar exposure and basal cell carcinoma. A review of the epidemiologic literature with meta-analysis focusing on particular methodological aspects

BACKGROUND

Numerous epidemiologic studies and a few systematic reviews have investigated the association between occupational solar exposure and basal cell carcinoma (BCC). However, previous reviews have several deficits with regard to included and excluded studies/risk estimates and the assessment of risk of selection bias (RoSB). Our aim was to review epidemiologic studies with a focus on these deficits and to use meta-(regression) analyses to summarize risk estimates.

METHODS

We systematically searched PubMed (including MEDLINE) and Embase for epidemiologic studies. Study evaluation considered four main aspects of risk of bias assessments, i.e. Selection of subjects (selection bias); Exposure variables; Outcome variables; Data analysis.

RESULTS

Of 56 identified references, 32 were used for meta-(regression) analyses. The overall pooled risk estimate for BCC comparing high/present vs. low/absent occupational solar exposure was 1.20 (95% CI 1.02-1.43); among studies without major deficits regarding data analysis, it was 1.10 (95% CI 0.91-1.33). Studies with low and high RoSB had pooled risk estimates of 0.83 (95% CI 0.73-0.93) and 1.95 (95% CI 1.42-2.67), respectively. The definitions of exposure and outcome variables were not correlated with study risk estimates. Studies with low RoSB in populations with the same latitude or lower than Germany had a pooled risk estimate of 1.01 (95% CI 0.88-1.15).

CONCLUSION

Due to the different associations between occupational solar exposure and BCC among studies with low and high RoSB, we reason that the current epidemiologic evidence base does not permit the conclusion that regular outdoor workers have an increased risk of BCC.

Possible Explanations for Rising Melanoma Rates Despite Increased Sunscreen Use over the Past Several Decades

The incidence of cutaneous melanoma continues to rise despite the increased use of sunscreens within the last several decades. Some research even suggests that the use of sunscreen is associated with increased rates of melanoma. Given the aggressive, and often deadly, nature of cutaneous melanoma, the aim of this communication is to better elucidate the relationship between sunscreen use and melanoma development and if there are other preventative measures to be aware of. A search was performed to identify the studies that have investigated melanoma development in individuals who used sunscreen and those who did not. Study limitations and possible confounding variables were identified, which guided a subsequent search to determine what data were available to support that these limitations and confounding variables may explain the perplexing association between sunscreen use and melanoma development. Five hypotheses were generated, which were related to increased awareness and reporting, the relationship between sunscreen use and the duration of sun exposure, the importance of broad-spectrum protection, and the effect of sunscreen on reactive oxygen species formation. The main conclusion is that more recent studies that control for confounding variables are required to determine the true effect of adequate broad-spectrum sunscreen use today on the development of melanoma.

Barriers and Facilitators in the Creation of a Surveillance System for Solar Radiation-Induced Skin Cancers

Outdoor workers are exposed to many hazards, including solar ultraviolet radiation (UVR). Identifying, reporting, analyzing and tracking the exposures or health outcomes of outdoor workers have not generally been formally considered. This article aims to summarize the best practices/strategies for creating an occupational sun exposure or skin cancer surveillance system for outdoor workers and to understand the key barriers and facilitators to the development of such a system. For the design of a successful occupational safety and health (OSH) surveillance system five occupational surveillance strategies are summarized: exposure registry, disease registry, disease screening/medical surveillance, sentinel event surveillance, and disease surveillance via data linkage. Ten key considerations are identified, including identifying a clear goal, a defined target population and stakeholder involvement, five critical barriers are highlighted including underreporting and funding, and five vital facilitators are recognized including communication/collaboration and a simple reporting process.

Indoor Versus Outdoor: Does Occupational Sunlight Exposure Increase Melanoma Risk? A Systematic Review

INTRODUCTION

Melanoma is the fifth most common cancer diagnosed in the United States, representing 5.6% of all new cancer cases. There are conflicting reports correlating a relationship between primarily outdoor occupations, associated with increased exposure to direct sunlight, and the incidence of cutaneous melanoma. Our objective was to outline and critically evaluate the relevant literature related to chronic occupational exposure to sunlight and risk of developing cutaneous melanoma.

METHODS

The study protocol for this systematic review was submitted to the International Prospective Register of Systematic Reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. For each relevant study included, the following information was extracted: author names, publication year, study name, study design, age, exposure assessment, outcome, comparison, number of cases, case ascertainment, and descriptive and adjusted statistics. Study quality and evidence certainty was assessed using the Grading of Recommendations, Assessment, Development and Evaluations model.

RESULTS

The initial database search yielded 1629 articles for review and following full-text screening, a total of 14 articles were included for final analysis. Of the studies included, seven articles were retrospective case control and seven were cohort studies. The studies did not report any differences in the likelihood of cutaneous melanoma development based upon membership in the outdoor versus indoor occupation groups included in each study.

CONCLUSIONS

Overall, the articles included in this systematic review did not report an increased risk of developing cutaneous melanoma among individuals with outdoor occupations. Further investigation is required to determine if other occupational or life-style-related risk factors exist, to help support the development of individualized skin screening recommendations and improve the early detection of melanoma in all populations.

Epidemiology of skin diseases in Germany: systematic review of the current state of research - part 1: cutaneous tumor diseases

Epidemiological data are of great importance for the identification of health care needs, the detection of gaps in care, the development of targeted prevention measures, and for the optimization of resource allocation. The aim of this work was to systematically collect all previously published population-based epidemiological data on skin diseases in Germany. The present part 1 of the publication series deals with tumor diseases of the skin. The results on non-infectious (part 2) and infectious skin diseases (part 3) form the other parts of this publication series. A systematic search of the literature spanning the last 15 years was conducted using the PubMed/MEDLINE database. With the aim of including all dermatologic diseases, a diagnostic list was developed based on the ICD-11 catalogue. This list included 1,347 skin diseases and formed the basis for the search. The literature search yielded 4,650 publications. After two-stage screening, 72 studies on 43 different skin diseases were included in the synthesis. Among them were 30 publications on cutaneous tumor diseases, the majority was related to malignant melanoma. This work is the first systematic literature review that aimed to report all available epidemiological data on skin diseases in Germany. In terms of study characteristics, a high heterogeneity was found for the different skin diseases. Even though the methodology of the included epidemiological studies varied considerably, the usefulness of these epidemiological data is extremely wide-ranging. Thus, this work can serve as a reference for various epidemiological questions.

Educating outdoor workers using tailored and financial messages to encourage safe-sun behaviors

Excessive and unsafe sun exposure represents a concerning hazard to the health of individuals. Of particular interest are those who are most susceptible to sun exposure, such as outdoor workers. The current study used a 3 × 2 between-subjects design to investigate the effectiveness of messages that varied the extent of personalization (i.e. generic message; occupation targeted message; individual tailored message) and the inclusion of content regarding financial consequences of skin cancer. Participants (N = 304) were recruited from the USA through Amazon's Mechanical Turk and randomly assigned to view a generic message, occupation targeted message, or individual tailored message. Additionally, participants were randomly assigned to view messages in which financial information was either present or not. Participants responded to questions assessing pre- and post-test sun protection behaviors. Individual tailored messaging was as effective as occupation targeted messaging, with both being more effective than generic messaging. This finding indicates that some degree of personalization is necessary when promoting safe-sun practices to outdoor workers, but that tailoring to individuals may not always be necessary. Inclusion of financial content in messaging resulted in greater intentions to practice sun protection behaviors. Results provide insight into effective methods for promoting sun protection.

Occupation and cutaneous melanoma: a 45-year historical cohort study of 14·9 million people in five Nordic countries

BACKGROUND

The age-adjusted incidence of cutaneous melanoma (CM) in the Nordic countries has increased during the last 60 years. Few prospective population-based studies have estimated the occupational variation in CM risk over time.

OBJECTIVES

To determine occupational variation in CM risk.

METHODS

A historical prospective cohort study with a 45-year follow-up from 1961 to 2005 (Nordic Occupational Cancer Study, NOCCA) based on record linkages between census and cancer registry data for Nordic residents aged 30-64 years in Denmark, Finland, Iceland, Norway and Sweden. National occupational codes were converted to 53 occupational categories, and stratified into indoor, outdoor and mixed work, and into socioeconomic status. The standardized incidence ratios (SIRs) were estimated as observed number of CM cases divided by the expected number calculated from stratum-specific person-years and national CM incidence rates.

RESULTS

During a follow-up of 385 million person-years, 83 898 incident cases of CM were identified. In all countries combined, men with outdoor work had a low SIR of 0·79 [95% confidence interval (CI) 0·77-0·81] and men with indoor work had a high SIR of 1·09 (95% CI 1·07-1·11). Differences in women pointed in the same direction. High socioeconomic status was associated with an excess risk: SIR 1·34 (95% CI 1·28-1·40) in men and SIR 1·31 (95% CI 1·26-1·36) in women. Technical, transport, military and public safety workers with potential skin exposure to carcinogens had excess risks.

CONCLUSIONS

Occupational variation in CM risk may be partly explained by host, socioeconomic and skin exposure factors. Differences in CM risk across socioeconomic groups attenuated slightly over time.

Sunscreens and their usefulness: have we made any progress in the last two decades?

Sunscreens have now been around for decades to mitigate the Sun's damaging ultraviolet (UV) radiation which, although essential for the existence of life, is a recognized prime carcinogen. Accordingly, have suncreams achieved their intended purposes towards protection against sunburns, skin photo-ageing and the like? Most importantly, however, have they provided the expected protection against skin cancers that current sunscreen products claim to do? In the last two decades, there have been tens, if not hundreds of studies on sunscreens with respect to skin protection against UVB (280‒320 nm)-traditionally sunscreens with rather low sun protection factors (SPF) were intended to protect against this type of radiation-and UVA (320‒400 nm) radiation; a distinction between SPF and UVA protection factor (UVA-PF) is made. Many of the studies of the last two decades have focused on protection against the more skin-penetrating UVA radiation. This non-exhaustive article reviews some of the important facets of what is currently known about sunscreens with regard (i) to the physical UV filters titanium dioxide (TiO₂) and zinc oxide (ZnO) and the mostly photo-unstable chemical UVB/UVA filters (e.g., octinoxate (OMC) and avobenzone (AVO), among others), (ii) to novel chemical sunscreen agents, (iii) to means that minimize the breakdown of chemical filters and improve their stability when exposed to UV sunlight, (iv) to SPF factors, and (v) to a short discussion on non-melanoma skin cancers and melanoma. Importantly, throughout the article we allude to the safety aspects of sunscreens and at the end ask the question: do active ingredients in sunscreen products pose a risk to human health, and what else can be done to enhance protection? Significant loss of skin protection from two well-known commercial suncreams when exposed to simulated UV sunlight. Cream I: titanium dioxide, ethylhexyl triazone, avobenzone, and octinoxate; Cream II: octyl salicylate, oxybenzone, avobenzone, and octinoxate.

Epidemiology of nonmelanoma skin cancer in Japan: Occupational type, lifestyle, and family history of cancer

Skin cancer is the most frequently diagnosed cancer in the fair-skinned population. In recent years, the incidence of nonmelanoma skin cancer (NMSC) has been increasing worldwide. However, there is no epidemiological study on skin cancer in the Asian population. A prospective cohort study including 140 420 participants was initiated in 1990 for cohort Ⅰ and 1993 for cohort Ⅱ at baseline survey from 11 public health center (PHC) areas. Of these participants, 284 NMSC cases were diagnosed during the follow-up period (through 2012 in the Osaka PHC area and 2013 in the other PHC areas). The Cox proportional hazards model was used to estimate hazard ratios and 95% confidence intervals (CI) for NMSC incidence according to occupational type, lifestyle factors (alcohol consumption, coffee consumption, smoking status, physical activity, and body mass index), and family history of cancer. Among men, compared with indoor workers, outdoor workers were associated with 2.18 (95% CI, 1.17-4.04) higher risk of squamous cell carcinoma (SCC) but not of basal cell carcinoma (BCC). Furthermore, men who have a family history of cancer had 1.99 (95% CI, 1.10-3.62) higher SCC risk. In women, we did not observe any association between occupational type and the risk of SCC (1.26; 95% CI, 0.68-2.32) or BCC (0.74; 95% CI, 0.42-1.28). In conclusion, men who are outdoor workers or have a family history of cancer had an increased risk of SCC.

Non-Melanoma Skin Cancer in Outdoor Workers: A Study on Actinic Keratosis in Italian Navy Personnel

Occupational exposure to ultraviolet radiation is one of the main risk factors for non-melanoma skin cancer (NMSC) development. The most common variants of NMSC are basal cell carcinomas, squamous cell carcinomas, and actinic keratosis (AK). The latter is nowadays considered by most authors as an early squamous cell carcinoma rather than a precancerous lesion. Outdoor workers have a higher risk of developing NMSC because they spend most of the working day outside. The aim of this descriptive study was to assess the prevalence of skin lesions, especially AK, in a professional category of individuals exposed to ultraviolet (UV) radiation: the Italian Navy. From January to June 2016, a questionnaire and a total skin examination of 921 military personnel were administered by medical specialists (dermatologists) in seven different Italian Navy centres. AK was detected in 217 of 921 (23.5%) workers. Older age, outdoor occupation, longer working life, and fair skin seem to promote the development of AK. Of the 217 workers with AK, 187 (86.2%) had lesions in chronically sun-exposed skin areas. Italian Navy personnel have a high AK prevalence. Further studies are needed to investigate occupational hazards and their health effects among outdoor workers to promote protective behaviour and raise awareness of skin cancer.

Male Sex is an Inherent Risk Factor for Basal Cell Carcinoma

Basal cell carcinoma (BCC) is more frequent among females <40 years old; however, it affects preferentially older males (>60 years old). In order to contribute to the study of the still largely unknown mechanisms that underlie this peculiar sex-dependent shift, we compared the kinetics of the increase of the age-specific BCC incidence rates (R) as a function of age in males and females. Studies reporting sex-stratified R were found using a PubMed search and male to female age-specific incidence rate ratios (RR) were calculated for each age-class as reported in each study and assigned to the mean of the corresponding age periods. Trends in age were assessed with Kendall's τ test and relationships between two variables by inverse variance method-weighed Loess and linear regression analysis. Sixteen data sets were eligible and confirmed a significant shift in the male to female ratio (Kendall's τ = 0.530; P < 0.001). Moreover, the slope parameter b = 1.205 (SE = 0.014) of the best fit (r ² = 0.980) regression line resulting by plotting male vs. female age-specific incidence rates predicts a statistically significant (P = 0.001), constant, about 20% faster increase of R in males of all ages. Similar relationship are also evident for cutaneous squamous cell and Merkel cell carcinoma and, even more intriguing, for sums of all cancers (excluding BCC and SCC) in many different registries. In conclusion, females are probably born with an inherently higher risk to develop BCC; however, also with a much slower increase rate of this risk as a function of age. Notably this observation seems to be not a BCC peculiarity. Because of its high incidence coupled with moderate morbidity and extremely low mortality rates, BCC may serve as a valuable, single-tumor paradigm to reproach the complex mechanisms that underline the interaction of age and sex in the pathogenesis of human malignancies.

Skin cancer protective behaviors among welders of west of Iran: Importance of access to protective equipment

BACKGROUND

Welders are normally at risk of skin cancer due to continuous contact with natural ultraviolet rays and welding radiation. Protective behaviors against the radiations are the most fundamental measures taken to prevent skin cancer in these individuals.

AIMS

This research aimed to evaluate the factors affecting the protective behaviors in welders.

PATIENTS/METHODS

In this cross-sectional research, participants were selected by the census method, and the research tool was a reliable and valid questionnaire filled by 154 welders in Yasuj, Iran. Data analysis was performed in SPSS version 16 using ANOVA, Pearson's correlation coefficient, and independent t test.

RESULTS

The highest age frequency was related to the age-group of 36-45 years, and the highest frequency of work experience was less than 10 years. In terms of the level of education, most welders had a diploma or a higher degree. In addition, most behaviors reported included using gloves, whereas the least applied method was using sunscreen cream, the most important cause of which was the high cost of the cream. In this regard, the Pearson's correlation coefficient demonstrated a negative association between skin cancer and job difficulty. In addition, performing of protective behaviors decreased in the target group by aging.

CONCLUSION

Given the unfavorable mean skin cancer protective behaviors in the welders, it is recommended that interventions, such as planned education, access to protective tools, and periodic skin examinations by a physician, be carried out to promote the health of these individuals and facilitate performing protective behaviors.

'Try to make good hay in the shade - it won't work!' A qualitative interview study on the perspectives of Bavarian farmers regarding primary prevention of skin cancer

BACKGROUND

Extensive exposure to solar ultraviolet radiation (UVR) is the main risk factor for keratinocyte carcinoma (KC), making outdoor workers, including farmers, a high-risk population for KC. The use of sun protection is crucial for KC prevention but is not typically implemented by outdoor workers during their daily tasks.

OBJECTIVES

To explore the attitudes of Bavarian farmers regarding sun-protective measures in their daily work and to understand perceived barriers and unmet needs.

METHODS

Farmers were recruited through the Bavarian Farmers Association in Bavaria, Southern Germany. Qualitative semi structured interviews were conducted with participants between December 2017 and March 2018. Interviews were recorded, transcribed verbatim and analysed using qualitative content analysis.

RESULTS

Twenty farmers (11 women, nine men; nine aged 18-30 years, 11 aged > 60 years) participated. Knowledge and awareness of UVR exposure and KC, perceived individual barriers to implementing sun-protective measures, individual experiences and farm life-specific circumstances emerged as key areas influencing the perspectives of farmers regarding the primary prevention of KC. Female farmers tended to take a more positive stance on sun protection, whereas male farmers showed a lower overall interest.

CONCLUSIONS

Knowledge and awareness of KC and UVR exposure is very limited in Bavarian farmers with serious perceived barriers due to the demands of daily agricultural work. Further qualitative studies are needed to identify intervention options that can increase skin cancer awareness and that can successfully overcome real barriers to implementing sun protection.

Dermoscopy Patterns and Histopathological Findings in Nodular Basal Cell Carcinoma-Study on 68 Cases

Basal cell carcinoma (BCC) is the most common skin cancer, with an increasing incidence in Europe particularly in young individuals. Nodular basal cell carcinoma is the most common subtype and accounts for approximately 57.6-78.7% of all BCCs. We performed an observational, morphological study which involved 68 patients with the diagnosis of nodular BCC. The localization and diameter of the lesion, histological subtype of the lesion, dermoscopic patterns, Fitzpatrick skin type and sex of each patient were recorded. The most common dermoscopic pattern seen in nodular BCCs was irregular vascularity and, arborizing vessels (>0.2mm in diameter) being the most frequent irregular vascular pattern. The second most common dermoscopic feature in patients with nodular BCCs was translucency. The most common dermoscopic features of the 12 pigmented BCCs were: pigmented islands (blue-gray globules and blue-gray ovoid nests); the pigmented distribution pattern (with (maple leaf-like structures and spoke wheel-like areas); arborizing vessels and white streaks/white areas. The histopathological analysis of the 68 BCCs revealed that the nodular type was the most frequently identified for 71.7% of cases The differential diagnosis between basal cell carcinoma and other skin lesions and inflammatory skin diseases is very important, since serious morbidity may result from an undiagnosed tumor.

Basal cell carcinoma: Epidemiology; pathophysiology; clinical and histological subtypes; and disease associations

As the most common human cancer worldwide and continuing to increase in incidence, basal cell carcinoma is associated with significant morbidity and cost. Continued advances in research have refined both our insight and approach to this seemingly ubiquitous disease. This 2-part continuing medical education article will provide a comprehensive and contemporary review of basal cell carcinoma. The first article in this series describes our current understanding of this disease regarding epidemiology, cost, clinical and histopathologic presentations, carcinogenesis, natural history, and disease associations.

Does sunlight protect us from cancer?

The Ultraviolet (UV) radiation contained in sunlight is a powerful mutagen and immune suppressant which partly explains why exposure to solar UV is the biggest risk factor for the development of cutaneous tumours. Evidence is building that sunlight may be protective against some internal malignancies. Because patients with these tumours are often vitamin D deficient, this has led some to propose that vitamin D supplementation will be beneficial in the treatment of these cancers. However, the results from already completed trials have been disappointing which has given weight to the argument that there must be something else about sunlight that explains its cancer-protecting properties.

Different outdoor professions have different risks - a cross-sectional study comparing non-melanoma skin cancer risk among farmers, gardeners and mountain guides

BACKGROUND

One of the main risk factors for non-melanoma skin cancer (NMSC), the most common cancer worldwide, is solar ultraviolet radiation (UVR). This has led to the recognition of NMSC as occupational disease for outdoor workers in several countries. However, outdoor professions are a very heterogeneous group with diverse daily activities and associated UVR exposure.

OBJECTIVE

To compare the prevalence of NMSC and associated risk behaviour in different outdoor professions.

METHODS

Cross-sectional study among outdoor workers (farmers, gardeners, mountain guides) and indoor workers (office employees) as control group using a paper-based questionnaire on UVR exposure and protective behaviour followed by a skin examination by a dermatologist.

RESULTS

A total of 563 participants (46.9% women, 46.9 ± 13.8 years) consisting of 348 outdoor workers (38.8% farmer, 35.3% gardener, 25.9% mountain guides) and 215 indoor workers were included in the study between March and September 2017. NMSC incl. actinic keratosis was diagnosed in 33.3% of mountain guides, 27.4% of farmers, 19.5% of gardeners and in 5.6% of indoor workers. Significant differences were seen between the outdoor professions with mountain guides at highest risk compared to farmers (OR = 2.6, 95% CI = 1.2-5.7). Substantial differences between the professions were also seen in skin cancer screening attendance rates (indoor worker 61.4%, mountain guides 57.8%, farmers 31.9%, gardeners 27.6%), daily UVR exposure during work and protective behaviour such as sunscreen use during work.

CONCLUSION

Different outdoor professions have significant different risks for NMSC and show different risk behaviour. Tailoring prevention efforts to different professions based on their individual needs could be the key to lower the global burden of (occupational) NMSC.

Knowledge, attitudes, and sun-safety practices among agricultural workers in the Autonomous Province of Trento, North-Eastern Italy (2016)

BACKGROUND

The purpose of this study was to determine and evaluate sun safety knowledge, attitudes and practices (KAP) among agricultural workers (AWs) in the Autonomous Province of Trento (North-Eastern Italy).

METHODS

A cross sectional study was performed among AWs who attended pesticide training courses (2016). Participants received a structured questionnaire focusing on KAP towards sun protective behaviors. Synthetic scores for knowledge (GKS), risk perception (RPS), behavioral adaptation and use of personal protective equipment (SPPS) were calculated. Regression analysis was modelled in order to assess GKS, RPS and individual factors as predictors of SPPS.

RESULTS

The sample included 204 AWs (89.7% males, 10.3% females, mean age 43.9±15.9 years). Sun protective behaviors were irregularly referred by participants, in particular receiving medical skin assessment by a dermatologist (33.8%), avoiding sun radiations at noon and taking rest breaks in shady areas (30.9%), and wearing sunscreen (13.3%). GKS was correlated with RPS, and RPS was characterized as a significant predictor of SPPS (B=0.307; 95% CI 0.224-0.389, P<0.001), alongside increased seniority (B=4.957: 95% CI 3.064-6.851, P<0.001) and previous history of sunburns (B=5.829; 95% CI 1.520-10.139, P=0.008).

CONCLUSIONS

Our findings indicate that AWs are not appropriately aware of the risks associated with occupational exposure to solar radiation, and eventually report inadequate skin cancer prevention practices. Since SPPS found significant predictors in individual factors, tailored interventions and training may contribute to fill knowledge gaps and raise the concerns of AWs towards occupational dermatological disorders.

Chemical and Physical Exposures in the Emerging US Green-Collar Workforce

OBJECTIVE

"Green collar" workers serve in occupations that directly improve environmental quality and sustainability. This study estimates and compares the prevalence of select physical and chemical exposures among green versus non-green U.S. workers.

METHODS

Data from the U.S. 2010 National Health Interview Survey (NHIS) Occupational Health Supplement were linked to the Occupational Information Network (ONET) Database. We examined four main exposures: 1) vapors, gas, dust, fumes (VGDF); 2) secondhand tobacco smoke; 3) skin hazards; 4) outdoor work.

RESULTS

Green-collar workers were significantly more likely to report exposure to VGDF and outdoor work than nongreen-collar workers [adjusted odds ratio (AOR) = 1.25; 95% CI = 1.11 to 1.40; AOR = 1.44 (1.26 to 1.63), respectively]. Green-collar workers were less likely to be exposed to chemicals (AOR = 0.80; 0.69 to 0.92).

CONCLUSIONS

Green-collar workers appear to be at a greater risk for select workplace exposures. As the green industry continues to grow, it is important to identify these occupational hazards in order to maximize worker health.

Occupation and relative risk of cutaneous squamous cell carcinoma (cSCC): A 45-year follow-up study in 4 Nordic countries

BACKGROUND

The age-adjusted incidence of cutaneous squamous cell carcinoma (cSCC) in the Nordic countries has increased during the last 60 years, and the identification of occupational variation in the relative risk of cSCC may have preventive implications.

OBJECTIVE

We sought to describe variation in the relative risk of cSCC between occupational categories in Finland, Iceland, Norway, and Sweden.

METHODS

This is a historical prospective cohort study based on record linkages between census data for 12.9 million people and cancer registry data from 1961 to 2005. Standardized incidence ratios for cSCC were estimated for 53 occupational categories with the cSCC incidence rates for the national population of each country used as reference.

RESULTS

During follow-up, 87,619 incident cases of cSCC were reported to the national cancer registries. In all countries combined, significant increased standardized incidence ratios were observed among seamen, military personnel, public safety workers, technical workers, teachers, transport workers, physicians, dentists, nurses, other health workers, religious workers, clerical workers, administrators, and sale agents (standardized incidence ratios between 1.08 and 1.77).

LIMITATIONS

Information on occupation was based on 1 point in time only.

CONCLUSION

The occupational variation of the relative risk of cSCC might be associated with socioeconomic factors, and to some extent to occupational exposures.

Basal cell carcinoma, squamous cell carcinoma and melanoma of the head and face

Ultraviolet light (UV) is an important risk factor for cutaneous basal cell carcinoma, cutaneous squamous cell carcinoma and cutaneous melanoma of the skin. These cancers most commonly affect persons with fair skin and blue eyes who sunburn rather than suntan. However, each of these cancers appears to be associated with a different pattern of UV exposure and to be mediated by different intracellular molecular pathways.

Some melanocortin 1 receptor (MC1R) gene variants play a direct role in the pathogenesis of cutaneous basal cell carcinoma, cutaneous squamous cell carcinoma and cutaneous melanoma apart from their role in determining a cancer-prone pigmentory phenotype (fair skin, red hair, blue eyes) through their interactions with other genes regulating immuno-inflammatory responses, DNA repair or apoptosis.

In this short review we focus on the aetiological role of UV in cutaneous basal cell carcinoma, cutaneous squamous cell carcinoma and cutaneous melanoma of the skin, and on some associated biopathological events.

The Sustainability of an Occupational Skin Cancer Prevention Program

OBJECTIVE

Sustainability of prevention programs is a public health goal.

METHODS

The effectiveness of Go Sun Smart, an occupational skin cancer prevention program, was evaluated 5 to 7 years out from the conclusion of a controlled randomized dissemination trial that compared an enhanced versus basic dissemination strategy at 53 ski areas enrolled in the trial.

RESULTS

Employees (n = 2940) at ski areas in the enhanced condition reported fewer sunburns but did not differ from employees in the basic condition on other sun-protection measures. Significant differences for all sun-protection practices were identified at ski areas that displayed nine or more Go Sun Smart materials or a combined total of nine or more Go Sun Smart and other sun safety messages.

CONCLUSIONS

Exposure to prevention messages is an important determinant of program effectiveness and potentially of program sustainability.

Basal cell carcinoma in farmers: an occupation group at high risk

Introduction

Skin cancer is the most commonly diagnosed cancer type worldwide, and 80 % of skin cancers are basal cell carcinoma (BCC). The main risk factor for developing BCC is exposure to ultraviolet radiation (UVR), particularly high-dose exposure at a young age. Outdoor workers, particularly farmers, are at high risk of developing BCC. However, studies of BCC in this population are scant.

Objective

To comprehensively evaluate all cases of BCC of the head and neck region treated during the years 2007–2013 at our hospital in Poland, and to compare the tumour characteristics in farmers to non-farmers.

Materials and methods

Retrospective analysis of 312 patients treated for head and neck BCC during the study period (2007–2013).

Results

Most patients (198 cases; 63 %) were males, with 114 females (37 %). Median age was 73 years (range 32–96 years). The most common tumour location was the nose and cheek (114 pts; 37 %) followed by the auricle (82 pts; 26 %), lips (54 pts; 18 %), scalp (26 pts; 8 %), and eye (36 pts; 12 %). The most common disease stage on presentation was stage T2 (104 pts, 33 %), followed by stage T1 (79 pts; 25 %), stage T3 (89 pts; 28 %), and stage T4 (40 pts; 14 %). By occupation, farmers accounted for 33 % of all patients (102 of 312 pts). The most common tumour localisations in the farmer subgroup were the nose and cheek (50 pts; 49 %; p < 0.001; odds ratio [OR] 2.19; 95 % confidence interval [CI] 1.35–3.57), followed by the auricle (32 pts; 31 %), scalp (16 pts; 16 %), ocular region (3 pts; 3 %), and lips (1 pt; 1 %). Patients in the farmer group were significantly younger than non-farmers (62 vs. 73 years; p < 0.001; OR 0.90, 95 % CI 0.88–0.93). Farmers were significantly more likely to present disease recurrence (27 vs. 12 % of cases; p < 0.001; OR 5.94; 95 % CI 2.86–12.33).

Conclusion

The results highlight the increased incidence and risk of recurrence of BCC in farmers. It is therefore necessary to consider enhancing educational programmes and other preventative measures in this occupational group and to evaluate the effectiveness of such programmes.

UVR exposure and vitamin D in a rural population. A study of outdoor working farmers, their spouses and children

BACKGROUND

Living and working in the countryside may result in excessive UVR exposure, with increased risk of skin cancer. Some sun exposure is, however, recommended, since vitamin D production is UVB-dependent.

OBJECTIVES

To examine UVR exposure and vitamin D levels in a rural population of outdoor working male farmers, their indoor working spouses and their children, expected to receive high UVR exposure.

METHODS

Prospective, cohort study. During the summer 2009 daily, personal UVR exposure and sun behaviour were recorded by dosimetry and diaries (17 403 days). Vitamin D was measured at the end of summer and the following winter.

RESULTS

Risk behaviour (= exposure of shoulders/upper body to the sun), beach days, sunscreen use and sunburns were infrequent. Farmers and boys had the highest daily UVR exposure (both 1.5 SED per day), likewise on work days. On non-work days the UVR exposure was even higher (up to 2.0 SED per day). Farmers, girls and boys had a higher chronic UVR exposure than the spouses, who had more intermittent high UVR exposure. Vitamin D levels did not differ between family members. At the end of summer 16% of the participants were vitamin D insufficient, the following winter, 61%. Some UVR exposure variables correlated positively, but weakly, with vitamin D levels.

CONCLUSIONS

UVR exposure was generally high among this study population, however, vitamin D levels still dropped below the recommended level during winter for most participants. Differences in UVR exposure between the groups did not result in differences in vitamin D levels.

Exponentially increasing incidences of cutaneous malignant melanoma in Europe correlate with low personal annual UV doses and suggests 2 major risk factors

For several decades the incidence of cutaneous malignant melanoma (CMM) steadily increased in fair-skinned, indoor-working people around the world. Scientists think poor tanning ability resulting in sunburns initiate CMM, but they do not understand why the incidence continues to increase despite the increased use of sunscreens and formulations offering more protection. This paradox, along with lower incidences of CMM in outdoor workers, although they have significantly higher annual UV doses than indoor workers have, perplexes scientists. We found a temporal exponential increase in the CMM incidence indicating second-order reaction kinetics revealing the existence of 2 major risk factors. From epidemiology studies, we know one major risk factor for getting CMM is poor tanning ability and we now propose the other major risk factor may be the Human Papilloma Virus (HPV) because clinicians find β HPVs in over half the biopsies. Moreover, we uncovered yet another paradox; the increasing CMM incidences significantly correlate with decreasing personal annual UV dose, a proxy for low vitamin D3 levels. We also discovered the incidence of CMM significantly increased with decreasing personal annual UV dose from 1960, when it was almost insignificant, to 2000. UV and other DNA-damaging agents can activate viruses, and UV-induced cytokines can hide HPV from immune surveillance, which may explain why CMM also occurs in anatomical locations where the sun does not shine. Thus, we propose the 2 major risk factors for getting CMM are intermittent UV exposures that result in low cutaneous levels of vitamin D3 and possibly viral infection.

Estimating the risk of squamous cell cancer induction in skin following nonlinear optical imaging

High power femto-second (fs) laser pulses used for in-vivo nonlinear optical (NLO) imaging can form cyclobutane pyrimidine dimers (CPD) in DNA, which may lead to carcinogenesis via subsequent mutations. Since UV radiation from routine sun exposure is the primary source of CPD lesions, we evaluated the risk of CPD-related squamous cell carcinoma (SCC) in human skin due to NLO imaging relative to that from sun exposure. We developed a unique cancer risk model expanding previously published estimation of risk from exposure to continuous wave (CW) laser. This new model showed that the increase in CPD-related SCC in skin from NLO imaging is negligible above that due to regular sun exposure.

Occupational UV exposure of environmental agents in Valencia, Spain

Excessive exposure to ultraviolet radiation (UVR) is considered the most important environmental risk factor in the development of melanoma and skin cancer. Outdoor workers are among those with the highest risk from exposure to solar UVR, as their daily activities constantly expose them to this radiation source. A study was carried out in Valencia, Spain, in summer 2012 and involved a group of 11 workers for a period of six 2-day recordings. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure erythemal UVR received by environmental agents in the course of their daily work. Median 2-day UV exposure was 6.2 standard erythema dose (SED), with 1 SED defined as effective 100 J m(-2) when weighted with the Commission Internationale de L'Eclairage's (CIE) erythemal response function. These workers were found to receive a median of 8.3% total daily ambient ultraviolet erythemal radiation. Comparison with the occupational UV exposure limit showed that the subjects had received an erythemal UV dose in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.

Analysis of the B-RafV600E mutation in cutaneous melanoma patients with occupational sun exposure

Sun-exposure is one of the risk factors associated with the development of a cutaneous neoplasm. In melanoma, the Ras-Raf-MEK-ERK (MAPK) signaling pathway is constitutively activated through multiple mechanisms, including B-RAF mutation. It has been hypothesized that B-RAF mutations in melanocytic lesions arise from DNA damage induced by ultraviolet (UV) radiation. However, it is still discussed if B-RAF mutations are associated with melanoma patients exposed to the sun. Therefore, in the present study, the known B-RAF^V600E mutation was analysed in melanoma samples from 30 indoor and 38 outdoor workers. B-RAF^V600E mutation was detected in 52 and 73% of outdoor workers and indoor workers, respectively. Of note, this mutation was identified in 12 of 14 (85%) melanoma of the trunk diagnosed in indoor workers and in 9 of 19 (47%) samples from outdoor workers (p=0.03). By analyzing melanomas of other body sites, no statistical difference in the frequency of B-RAF^V600E mutation was identified between the groups of workers. It appears that the mutation detected among indoor workers may be associated with a recreational or intermittent exposure to the sun, as usually the trunk is a sun-protected body site. Overall, these data indicate that the B-RAF^V600E mutation detected in melanoma is not associated with a chronic exposure to the sun. Mutations detected in other genes may also contribute to melanoma development in the subset of patients exposed to UV radiation.

Non-melanoma skin cancer: occupational risk from UV light and arsenic exposure

Non-melanoma skin cancer (NMSC) has a significant impact on public health and health care costs as a result of high morbidity and disfigurement due to the destruction of surrounding tissues. Although the mortality rates of these tumors are low, the high incidence rates determine a considerable number of deaths. NMSC is the most common type of skin cancer, representing about 1/3 of all malignancies diagnosed worldwide each year. The most common NMSC are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Studies on humans and experimental animals indicate that ultraviolet (UV) light and arsenic play important roles in the development of these skin malignancies. Several epidemiological studies have investigated the risk of developing NMSC and the potential link between exposure to sunlight and arsenic in the agricultural and industrial occupational settings. To date, the published literature suggests that there is no apparent skin cancer risk as regards workplace exposure to artificial UV light or arsenic. Concerning UV light from sun exposure at the workplace, most published studies indicated an elevated risk for SCC, but are less conclusive for BCC. Many of these studies are limited by the methodology used in the evaluation of occupational exposure and the lack of adjustment for major confounders. Therefore, further epidemiological studies are required to focus on exposure assessment at the individual level as well as potential interactions with other occupational and non-occupational exposures and individual susceptibility. In doing so, we can better quantify the true risk of skin cancer in exposed workers and inform effective public health prevention programs.

Sociodemographic and Psychological Correlates of Sun Protection Behaviors among Outdoor Workers: A Review

Outdoor workers are at a higher risk for developing skin cancer due to their increased sun exposure. The primary objective of this review was to synthesize the current research literature that addresses sociodemographic and psychological factors related to sun protection behaviors in outdoor workers. Two additional purposes were to provide an overview of sun exposure and describe sun protection behaviors of outdoor workers. To identify the studies for this review, a methodical search was performed in the PubMed, PsycInfo, MEDLINE, and ERIC databases. Fifteen studies met the review criteria. Despite regular and prolonged sun exposure, many outdoor workers fail to engage in sufficient sun protection behaviors. Correlates of outdoor workers' sun protection behaviors include being female, older age, being white, personal skin cancer history, time (hours/years) spent at work, sun safety training, perceived prioritization of sun protection, concern about sun exposure, workplace support, families' expectations, and familial information giving. However, limited attention is given to designing theoretically grounded studies to identify factors to inform future research. There is a need to conduct research based on solid theoretical foundations that explains the relationships among the factors in this domain.

Solar UV exposure in construction workers in Valencia, Spain

Exposure to ultraviolet radiation (UVR) has long been recognized as the most important environmental risk factor for melanoma and skin cancer. Outdoor workers are among the groups most at risk from exposure to solar UVR in their daily activities. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure the biologically effective UVR received by construction workers in the course of their daily work. The study took place in Valencia, Spain, in July 2010 and involved a group of eight workers for a period of 5 days. The median UV exposure was 6.11 standard erythema dose (SED) per day, with 1 SED defined as effective 100 J/m(2) when weighted with the Commission Internationale de L'Eeclairage erythemal response function. These workers were found to receive a median of 13.9% of total daily ambient ultraviolet erythemal radiation (UVER). Comparison with the occupational UVR exposure limit showed that the subjects had received UVER exposure in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.

Significant differences in nonmelanoma skin cancers of the upper and lower lip

BACKGROUND

Squamous cell carcinomas (SCCs) generally have been reported to be more prevalent on the lips than basal cell carcinomas (BCCs), but in our experience, BCCs of the lips are common, particularly in women.

OBJECTIVES

To determine the tumor characteristics of lip SCCs and BCCs, including tumor type, anatomic location, and size; and to identify the relationship between patient characteristics, including age and sex, and lip tumor characteristics.

METHODS AND MATERIALS

Retrospective review of all BCCs and SCCs located on the lip treated between January 1995 and October 2010.

RESULTS

Of 470 lip nonmelanoma skin cancers (NMSCs) identified, 71.4% were BCCs, and 28.6% were SCCs. Lower lip tumors were predominantly SCCs (79.8%, p < .01), whereas upper lip tumors were predominantly BCCs (85.7%, p < .01). Patients with lower lip tumors were significantly older (68.8 vs. 64.7, p = .02) and were largely male (70.8%, p < .01). Patients with SCCs were mostly male (62.2%, p = .02), whereas those with BCCs were predominantly female (68.8%, p < .01). Subgroup analysis showed that upper lip tumors were 98.1% cutaneous or more than 50% cutaneous, whereas 56.3% of lower lip tumors were mucosal or more than 50% mucosal; 87.1% of mucosal tumors were SCCs, whereas 83.6% of cutaneous tumors were BCCs (p < .01). Seventy-one percent of patients with mucosal tumors were men, whereas 67% of patients with cutaneous only tumors were women (p < .01).

CONCLUSION

These data provide evidence of significant differences in patient and tumor characteristics between NMSCs of the upper and lower lips.

Prevalence of exposure to solar ultraviolet radiation (UVR) on the job in Canada

OBJECTIVE

Over one third of all newly diagnosed cancers in Canada in 2010 were skin cancer, despite the fact that skin cancer is largely preventable by limiting ultraviolet radiation (UVR) exposure. Outdoor workers are at risk of exposure to UVR, yet the prevalence of exposure in Canada is unknown. The objective of this study was to estimate the number of outdoor workers in Canada.

METHODS

Building on CAREX Canada methods, we used a combination of data in the original Finnish CAREX, an Australian skin cancer prevention workbook, career-selection websites, and published studies to flag jobs at high risk of exposure. We also created a category for moderate exposure, where workers were unlikely to spend their whole day outside. Adjustments were made for industry-driven exposure, and prevalence of exposure was assigned for all jobs. Prevalence data were linked to census data to derive the number of workers exposed to solar UVR.

RESULTS

Over 1.5 million Canadian workers are exposed to solar UV at work, and approximately 897,000 of these were flagged as "high exposed" (outdoors > or =75% of the workday). The largest occupational groups were farmers, construction labourers, and landscapers. Proportions of the workforce exposed ranged by province, with 6.9% of workers exposed in Ontario, and up to 17.3% in Prince Edward Island.

CONCLUSIONS

Information on solar UVR exposure prevalence is needed for primary skin cancer prevention with regard to targeting of high-risk groups, priority setting, and better risk assessment. This study showed that solar UVR exposure is occurring on a large scale in Canada.

A systematic review of worldwide incidence of nonmelanoma skin cancer

BACKGROUND

  Nonmelanoma skin cancer (NMSC) is the most common cancer affecting white-skinned individuals and the incidence is increasing worldwide.

OBJECTIVES

This systematic review brings together 75 studies conducted over the past half century to look at geographical variations and trends worldwide in NMSC, and specifically incidence data are compared with recent U.K. cancer registry data.

METHODS

Following the development of a comprehensive search strategy, an assessment tool was adapted to look at the methodological quality of the eligible studies.

RESULTS

Most of the studies focused on white populations in Europe, the U.S.A. and Australia; however, limited data were available for other skin types in regions such as Africa. Worldwide the incidence for NMSC varies widely with the highest rates in Australia [>1000/100, 000 person-years for basal cell carcinoma (BCC)] and the lowest rates in parts of Africa (< 1/100, 000 person-years for BCC). The average incidence rates in England were 76·21/100, 000 person-years and 22·65/100, 000 person-years for BCC and squamous cell carcinoma (SCC), respectively, with highest rates in the South-West of England (121·29/100, 000 person-years for BCC and 33·02/100, 000 person-years for SCC) and lowest rates by far in London (0·24/100, 000 person-years for BCC and 14·98/100, 000 person-years for SCC). The incidence rates in the U.K. appear to be increasing at a greater rate when compared with the rest of Europe.

CONCLUSIONS

NMSC is an increasing problem for health care services worldwide. This review highlights a requirement for prevention studies in this area and the issues surrounding incomplete NMSC registration. Registration standards of NMSC should be improved to the level of other invasive disease.

Radon and skin cancer in southwest England: an ecologic study

BACKGROUND

Radon, a naturally occurring radioactive gas, is a carcinogen that causes a small proportion of lung cancers among exposed populations. Theoretical models suggest that radon may also be a risk factor for skin cancer, but epidemiologic evidence for this relationship is weak. In this study, we investigated ecologic associations between environmental radon concentration and the incidence of various types of skin cancer.

METHODS

We analyzed data for 287 small areas (postcode sectors) in southwest England for the years 2000-2004. Poisson regression was used to compare registration rates of malignant melanoma, basal cell carcinoma, and squamous cell carcinoma across mean indoor radon concentrations from household surveys. Analyses were adjusted for potentially confounding factors, including age, sex, population socioeconomic status, and mean hours of bright sunshine.

RESULTS

No association was observed between mean postcode sector radon concentration and either malignant melanoma or basal cell carcinoma registration rates. However, sectors with higher radon levels had higher squamous cell carcinoma registration rates, with evidence of an exposure-response relationship. Comparing highest and lowest radon categories, postcode sectors with mean radon ≥ 230 Bq/m(3) had registration rates 1.76 (95% confidence interval = 1.46-2.11) times those with mean radon 0-39 Bq/m(3). Associations persisted after adjustment for potential confounders.

CONCLUSIONS

This ecologic study suggests that environmental radon exposure may be a risk factor for squamous cell carcinoma. Further study is warranted to overcome ecologic design limitations and to determine whether this relationship is generalizable to national and international settings.

Prospective study of physical activity and risk of squamous cell carcinoma of the skin

BACKGROUND

The relationship between physical activity and risk of cutaneous squamous cell carcinoma (SCC) is unknown and difficult to investigate due to confounding by sun exposure. We prospectively examined the association of recreational and occupational physical activity and incidence of SCC accounting for photoaging and other risk factors.

METHODS

We used available information on physical activity from the Australian population-based Nambour Skin Cancer Study comprising 1,171 adults aged 25-75 years at baseline (1992). In sex-stratified analyses (person-based and tumor-based) we estimated the associations between type of activity and incidence of SCC prospectively to 2007.

RESULTS

During 16 years of follow-up, 98 men and 90 women newly developed SCC. We found no significant association between recreational activity measures and SCC after controlling for potential confounding factors including indicators of sun exposure. In men, the observed risk pattern was however suggestive of elevated risk with increasing total hours of recreational activity (compared to inactive men, RR (95%CI) 0.89 (0.54, 1.46) for ≤ 1.5 hrs/wk; 1.29 (0.82, 2.04) for ≤ 4.0 hrs/wk; 1.33 (0.86, 2.05) > 4.0 hrs/wk), while among women, higher level of occupational activity (standing and manual versus sedentary work activities) was associated with a reduced incidence of SCC tumors (P trend = 0.03).

CONCLUSIONS

Despite some suggestion that recreational activity in men and occupational activity in women are related to occurrence of SCC, there is no firm support for a role of physical activity in the development of cutaneous SCC.