Occupational sunlight exposure and cancer incidence among Swedish construction workers

Skin Cancer Prevention across the G7, Australia and New Zealand: A Review of Legislation and Guidelines

Incidence rates of melanoma and keratinocyte skin cancers have been on the rise globally in recent decades. While there has been a select focus on personal sun protection awareness, to our knowledge, there is a paucity of legislation in place to help support citizens' efforts to protect themselves from the harmful effects of ultraviolet radiation (UVR). Given this, we conducted a comprehensive review of legislation and guidelines pertaining to a variety of sun protection-related topics in countries of the Group of Seven (G7), Australia and New Zealand. Australia was the only country to have banned tanning beds for individuals of all ages, while other select countries have instituted bans for minors. In workplace policy, there is very little recognition of the danger of occupational UVR exposure in outdoor workers, and thus very few protective measures are in place. With regard to sports and recreation, certain dermatological/professional associations have put forward recommendations, but no legislation was brought forward by government bodies outside of Australia and New Zealand. With regard to youth, while there are various guidelines and frameworks in place across several countries, adherence remains difficult in the absence of concrete legislation and standardization of procedures. Finally, only Australia and a few select jurisdictions in the United States have implemented sales tax exemptions for sunscreen products. In light of our findings, we have made several recommendations, which we anticipate will help reduce the rates of melanoma and keratinocyte cancers in years to come. However, minimizing UVR exposure is not without risk, and we, therefore, suggest the promotion of vitamin D supplementation in conjunction with sun protective practices to limit potential harm.

Differences and Similarities in Epidemiology and Risk Factors for Cutaneous and Uveal Melanoma

Both cutaneous melanoma (CM) and uveal melanoma (UM) represent important causes of morbidity and mortality. In this review, we evaluate the available knowledge on the differences and similarities between cutaneous melanoma and uveal melanoma, focusing on the epidemiological aspects and risk factors. Uveal melanoma is a rare condition but is the most prevalent primary intra-ocular malignant tumor in adults. Cutaneous melanoma, on the other hand, is significantly more common. While the frequency of cutaneous melanoma has increased in the last decades worldwide, the incidence of uveal melanoma has remained stable. Although both tumors arise from melanocytes, they are very distinct entities biologically, with complex and varied etiologies. Both conditions are encountered more frequently by individuals with a fair phenotype. ultraviolet-radiation is an important, well-documented risk factor for the development of CM, but has shown not to be of specific risk in UM. Although cutaneous and ocular melanomas seem to be inherited independently, there are reported cases of concomitant primary tumors in the same patient.

Cumulative Sun Exposure and Melanoma in a Population-Based Case–Control Study: Does Sun Sensitivity Matter?

Simple Summary

Melanoma has been clearly shown to be related to sunburns and other types of intermittent sun exposure. It is less clear how cumulative sun exposure is related to melanoma. In this case–control study, the cumulative hours of sun exposure per day were examined between spring and fall each year over periods or decades of life to estimate lifetime hours of sun exposure. No associations were found before the age of 60. However, when stratified by fair skin color, we found little or no association with hours of sun exposure among fair-skinned individuals, but found an increased risk for higher hours of sun exposure among medium- or darker-skinned individuals for lifetime exposure.

Abstract

Cutaneous melanoma (CM) has consistently been associated with intermittent sun exposure, while the association with chronic sun exposure is debated. The goal of this research was to examine the complex relationship between CM, sun sensitivity and sun exposure based on theoretical concepts of how these factors may be associated. Detailed sun exposure histories across life periods and various measures of sun sensitivity were collected in a population-based case–control study of melanoma in Iowa, USA. Participants were asked about their hours of sun exposure per day between March and October each year over periods or decades of life to estimate cumulative lifetime hours of sun exposure. Increased odds ratios (ORs) for CM were seen for most standard measures of sun sensitivity except for the tendency to sunburn. Minimal associations were seen with total hours of sun exposure early in life. However, an interaction was seen between fair skin color and lifetime hours of sun exposure, where the strongest associations with CM were seen among medium-skinned and dark-skinned participants. This suggests that cumulative sun exposure at high levels may increase CM among non-sun-sensitive individuals typically at lower risk of CM. Such a finding has implications for the prevention effort for melanoma regarding time in the sun among darker-skinned individuals.

Temporal Aspects of the Association between Exposure to the World Trade Center Disaster and Risk of Cutaneous Melanoma

Rescue/recovery workers who responded to the World Trade Center (WTC) attacks were exposed to known/suspected carcinogens. Studies have identified a trend toward an elevated risk of cutaneous melanoma in this population; however, few found significant increases. Furthermore, temporal aspects of the association have not been investigated. A total of 44,540 non-Hispanic White workers from the WTC Combined Rescue/Recovery Cohort were studied between March 12, 2002 and December 31, 2015. Cancer data were obtained through linkages with 13 state registries. Poisson regression was used to estimate hazard ratios and 95% confidence intervals using the New York State population as the reference; change points in hazard ratios were estimated using profile likelihood. We observed 247 incident cases of melanoma. No increase in incidence was detected during 2002-2004. From 2005 to 2015, the hazard ratio was 1.34 (95% confidence interval = 1.18-1.52). A dose‒response relationship was observed by arrival time at the WTC site. Risk was elevated just over 3 years after the attacks. Whereas WTC-related exposures to UVR or other agents might have contributed to this result, exposures other than those at the WTC site, enhanced medical surveillance, and lack of a control group with a similar proportion of rescue/recovery workers cannot be discounted. Our results support continued study of this population for melanoma.

Dietary and circulating vitamin D and risk of renal cell carcinoma: a meta-analysis of observational studies

OBJECTIVE

This meta-analysis is the first to evaluate the associations of circulating and dietary intake of vitamin D with risk of risk of renal cell carcinoma (RCC). Our findings showed that higher circulating vitamin D level and dietary vitamin D intake were associated with a reduced risk of RCC. The possible explanation might be attributed to the anti-inflammatory effect, inhibiting cell proliferation, inducing cell differentiation and apoptosis.

MATERIALS AND METHODS

We searched the MEDLINE, EMBASE, and Scopus databases from their inception points through December 2018 for observational studies. The pooled relative risks (RRs) with corresponding 95% CIs were calculated using random-effects or fixed-effects models. The Newcastle-Ottawa scale was employed to assess the quality of the included studies.

RESULTS

A total of 9 publications were included in this meta-analysis. An overall analysis of the highest versus lowest intake levels revealed that circulating vitamin D level was protectively associated with risk of RCC 0.76 (95% CI: 0.64-0.89, P=0.001), with no evidence of heterogeneity (I2=38.8%, P=0.162). In addition, dietary vitamin D intake was associated with a reduced risk of RCC (RR: 0.86; 95% CI: 75-0.99, P=0.030). Statistical heterogeneity was not identified (I2=28.8%, P=0.199). Subgroup analyses results showed the gender differences, and the associations were significant in results with women participants (RR: 0.70; 95% CI: 0.55-0.88) and case-control studies (RR: 0.80, 95% CI: 0.67-0.95).

CONCLUSION

Higher circulating vitamin D level and higher dietary vitamin D intake both might be associated with a reduced risk of RCC. Further high-quality randomized controlled trials are required in the future to confirm our results.

Sunlamp use is a risk factor for uveal melanoma: a meta-analysis

OBJECTIVE

Advancements in the treatment of uveal melanoma have not improved survival; therefore, identifying modifiable risk factors is critical to improving outcomes. This study aims to investigate the association between sunlamp use and the development of uveal melanoma.

DESIGN

This study is designed as a meta-analysis.

METHODS

Literature was searched and reviewed through the MEDLINE (with both OVID and PubMed), EMBASE, MD Consult, and Web of Science databases. These databases were searched from 1966 to 2019 using the following keywords to identify articles examining risk factors for uveal melanoma: ultraviolet, sun, sunlight, uveal melanoma, eye cancer, eye melanoma, nevus, and risk factor. All articles were evaluated for inclusion based on methodology and data reporting association between sunlamp use and uveal melanoma. The Meta-analysis of Observational Studies in Epidemiology guidelines and the Newcastle-Ottawa Scale were used to assess data quality and validity. A random effects model was employed.

RESULTS

A total of 5 studies, enrolling a total of 1753 uveal melanoma cases and 3399 controls were included in this meta-analysis. The results of this study showed a positive association between sunlamp use and uveal melanoma (odds ratio = 2.15; 95% confidence interval 1.27-3.64). Meta-regression of between study heterogeneity did not reveal a statistically significant association when publication year, site latitude, melanoma tissue location (specifically, inclusion of iris tumors), or control type (population versus clinic) were evaluated.

CONCLUSION

This meta-analysis identified a statistically significant association between sunlamp use and uveal melanoma, supporting sunlamp use as a modifiable risk factor for uveal melanoma.

Sunlight exposure in association with risk of lymphoid malignancy: a meta-analysis of observational studies

PURPOSE

Several observational studies have shown contradictory results regarding the association between sunlight exposure and the risk of malignant lymphoma. Thus, we aimed to systematically determine the association between sunlight exposure and lymphoid malignancy risk through a meta-analysis.

METHODS

A thorough search of four electronic databases (PubMed, Embase, Web of Science, and Scopus) was performed to identify eligible studies until 13 August 2020. A random-effects model was used to calculate risk estimates of sunlight exposure. The main outcome measure was the risk of lymphoid malignancy subtypes with odds ratios (ORs) and 95% confidence intervals (CIs) according to various forms of solar ultraviolet radiation.

RESULTS

In total, 17 case-control studies and 9 cohort studies including 216,285 non-Hodgkin lymphoma (NHL) and 23,017 Hodgkin's lymphoma (HL) patients were included in the final analysis. Personal sunlight exposure was significantly associated with a decreased risk of HL (OR 0.77; 95% CI 0.68-0.87) and NHL (OR 0.81; 95% CI 0.71-0.92), including all subtypes except T-cell lymphoma. Ambient sunlight exposure at residence was associated with a reduced risk of HL (OR 0.88; 95% CI 0.81-0.95) and all NHL subtypes (OR 0.84; 95% CI 0.73-0.96), except for chronic lymphocytic leukemia/small lymphocytic lymphoma. As the number of sunburns and sunbaths increased, the risk of NHL tended to decrease.

CONCLUSION

While there was an observed protective effect both from case-control and prospective studies, substantial heterogeneity was found in the current study. Thus, more evidence is required to confirm that promoting sunlight exposure can prevent the development of lymphoid neoplasia.

Spectral transmission of solar radiation by plastic and glass materials

It is well known that excessive exposure to solar ultraviolet (UV) radiation can have serious adverse effects. Many everyday materials influence the UV radiation received by humans, for example, those used in construction and on the exterior of buildings such as plastics and glass can reduce the UV exposure of persons exposed to solar radiation. In this paper we analyse the spectral transmission of solar radiation of widely used materials using the transmittance parameter. The measurements were performed on clear days, at 8 h and 12 solar hours, in July 2018 (five days) and in January 2019 (three days). The spectral transmittances of these materials and the integrated transmittances in the UVB from 300 nm, UVA, visible (VIS) and near infrared ranges (NIR) were calculated. In summer in the UVB range from 300 nm methacrylate and smoked glass have the highest transmittance values (56%) and polycarbonate present the lowest (30%). In the VIS and NIR ranges methacrylate (95%) and smoked glass (80%) have the highest transmittances and polycarbonate the lowest (45%). In general the 8 h transmittances are higher than those at 12 h and are also higher in winter than summer. For two biological functions (erythemal and DNA-damage) and for the UVB range from 300 nm, the transmittance for most materials (except fibreglass) is in the range 6-14%. The exposure times obtained show that erythemal damage could occur after long exposure to solar radiation through the materials studied, information which should be made available to the general public.

Burden of occupational morbidity from selected causes in the United States overall and by NORA industry sector, 2012: A conservative estimate

BACKGROUND

Timely and reliable national estimates of the occurrence of occupational injury and illness are needed to monitor the burden of occupational morbidity and mortality, establish research and intervention priorities, and evaluate the progress and effectiveness of prevention efforts.

METHODS

We provide updated estimates of morbidity from occupational injuries and selected illnesses, using current general population incidence rates, the proportion of the general public with a particular workplace exposure, and the relative risk of illness from that exposure. We provide estimates for the total U.S. working population and for specific industry sectors.

RESULTS

We estimate that, in 2012, between 5 712 362 and 5 961 620 total occupational cases, including 0.7 to 1.0 million incident illnesses and 5.0 million injuries, occurred in the United States.

CONCLUSION

The variety of disparate data sources and methods required to compile these estimates highlight the need for more comprehensive and compatible occupational health surveillance in the United States.

Skin cancer risk perception and sun protection behavior at work, at leisure, and on sun holidays: a survey for Danish outdoor and indoor workers

BACKGROUND

To prevent occupational skin cancer, it is essential that the sun-protective behavior of outdoor workers is adequate. The aim is to study the sun-protective behavior of Danish outdoor workers at work, at leisure, and on sun holiday and compare it to that of indoor workers.

METHODS

This is a cross-sectional study, based on a 53-item survey completed by Danish outdoor (n = 380) and indoor workers (n = 119) in 2016-2017. Status as outdoor or indoor worker was decided based on self-report and behavioral differences were tested using (paired) t tests and multiple regression adjusted for age, sex, educational level, history of smoking, and skin type.

RESULTS

Danish outdoor workers at work use sun protection less than they do at leisure and on sun holiday (α < .05) where their sun protection behavior is similar to that of indoor workers. The proportion of Danish outdoor workers that always/often use sun protection at work is for shade seeking around noon 4.2%, sunscreen 34.5%, wide-brimmed hat 25.3%, and long trousers and shirt with sleeves 42.4%. Of Danish outdoor workers, 49.5% do not think about the risk of occupational skin cancer and 11.8% think the risk is insignificant, 32.4% think that the use of sun protection is of low or no importance, 84.2% consider sunburn important as skin cancer risk factor still 88.9% have a history of sunburn at work, > 80.0% agree that risk of skin cancer is reduced by the use of sun protection, and only 4.0% dismiss the possibility of sun protection use at work.

CONCLUSIONS

Skin cancer risk and use of sun protection at work are largely neglected in Danish outdoor workers, more so than at leisure and on sun holiday where their risk behavior resembles that of indoor workers. This indicates an untapped workplace preventive potential.

The Sun Solutions Intervention for Operating Engineers: A Randomized Controlled Trial

Background: Because Operating Engineers (heavy equipment operators) are outdoor workers at risk for skin cancer, interventions are needed to promote sun safety. The objectives were to determine changes in sunscreen use and sunburning among Operating Engineers randomized to four conditions in the Sun Solutions study: (i) education only; (ii) education and text message reminders; (ii) education and mailed sunscreen; and (iv) education, text message reminders, and mailed sunscreen.Methods: In this randomized controlled trial, Operating Engineers (N = 357) were recruited at required safety training sessions throughout Michigan during winter/spring of 2012 to 2013 and provided baseline surveys. The four interventions were delivered over the summer. Postintervention surveys were collected in the fall (82.1% follow-up).Results: Sunscreen use improved significantly from baseline to follow-up in all four conditions (P < 0.05), except sunscreen use among those receiving education and text message reminders was only marginally significant (P = 0.07). There were significantly greater increases in sunscreen use in the two conditions that were mailed sunscreen (P < 0.001). There was a significant decrease in the number of reported sunburns from baseline to follow-up in all four conditions (P < 0.001), but there were no significant differences in sunburns among the groups. Participant evaluated the interventions highly with those who received mailed sunscreen rating the intervention the highest.Conclusions: Providing proper sun-safety education and minimizing barriers to sunscreen use can increase sunscreen use and decrease reported sunburns.Impact: The implementation of the Sun Solutions intervention may be an effective method to modify skin cancer-related behaviors. Cancer Epidemiol Biomarkers Prev; 27(8); 864-73. ©2018 AACR.

Occupational ultraviolet exposure and risk of non-Hodgkin's lymphomas: a meta-analysis

Non-Hodgkin lymphoma is a heterogeneous group of lympho-proliferative disorders. We performed a meta-analysis to summarize the available evidence from case-control studies and cohort study on the inconsistent association between occupational sun exposure and the risk of non-Hodgkin lymphoma. We searched PubMed, ISI web of science, the Cochrane Library, EMBASE and reference lists for relevant articles. Study specific odds ratios or relative risk and 95% confidence intervals were pooled by using fixed-effects or random-effects models. Ten case-control studies and one cohort study were included in the meta-analysis. Overall, the pooled odds ratios for occupational ultraviolet exposure and non-Hodgkin lymphoma risk was 1.15(95% confidence intervals: 0.99, 1.32; I² = 44.4%). Occupational sun exposure was positively associated with the risk of NHL 1.14 (95% confidence intervals: 1.05, 1.23; I²=25.4% p for heterogeneity =0.202) in Caucasian population. Common subtypes of non-Hodgkin lymphoma and ultraviolet exposure had the negative results. The pooled odds ratios was 1.16, (95%confidence intervals: 0.90, 1.50) for T-cell non-Hodgkin lymphoma; 0.79, (95%confidence intervals: 0.61, 1.02) for B-cell non-Hodgkin lymphoma; 1.13, (95%confidence intervals: 0.96, 1.34) for chronic lymphocytic leukemia; 1.25, (95%confidence intervals: 0.95, 1.64) for males; 1.49, (95%confidence intervals: 0.99, 2.25) for females. Data suggested that occupational ultraviolet exposure was a risk factor for non-Hodgkin lymphoma in Caucasian population. While, there had no relationship between occupational ultraviolet exposure and risk of non-Hodgkin lymphoma in general population as well as non-Hodgkin lymphoma common subtypes. Besides, gender specific occupational sun exposure also indicated no association on risk of non-Hodgkin lymphoma.

Uveal Melanoma Risk Factors: A Systematic Review of Meta-Analyses

PURPOSE

There is currently no clinical risk-assessment tool allowing identification of patients at risk for developing uveal melanoma (UM) who might benefit from regular screening. As a first step toward the elaboration of such a tool, we systematically reviewed UM risk factors already established by meta-analysis.

METHODS

Two reviewers independently screened Pubmed, Medline, Embase, and Web of Science from their respective inception dates until July 2016 using a combination of keywords and MeSH terms. Eligible studies were meta-analyses or systematic reviews providing pooled odds ratios (ORs) of risk factors for UM development or sufficient information to calculate them. Methodological quality was evaluated using the Assessment of Multiple Systematic Reviews tool.

RESULTS

Four meta-analyses with a mean methodological quality score of 65.9% (min: 54.5%; max: 72.7%) were included. The following significant risk factors were identified: atypical cutaneous nevi (OR 2.82, 95% CI 1.10-7.26), welding (OR 2.05, 95% CI 1.20-3.51), occupational cooking (OR 1.81, 95% CI 1.33-2.46), fair skin color (OR 1.80, 95% CI 1.31-2.47), light eye color (OR 1.75, 95% CI 1.31-2.34), common cutaneous nevi (OR 1.74, 95% CI 1.27-2.39), propensity to sunburn (OR 1.64, 95% CI 1.29-2.09), iris nevi (OR 1.53, 95% CI 1.03-2.27), and cutaneous freckles (OR 1.27, 95% CI 1.09-1.49). Non-significant factors included outdoor leisure activity, occupational sunlight exposure, latitude of birth, and hair color.

CONCLUSION

Moderate quality of evidence determined nine significant risk factors for developing UM. Knowledge of these variables will assist researchers in the elaboration of a formal risk-assessment tool allowing clinicians to estimate susceptibility to the disease and necessity of regular screening.

Accuracy of clinical diagnosis for the identification of potentially malignant disorders and malignant lip lesions

The aim of this study was to assess the accuracy of clinical diagnosis for lip lesions based on sensitivity and specificity. The retrospective analysis focused on the detection of lesions caused by potentially malignant disorders (PMDs) and malignant lesions (n = 1195). All cases were classified as benign, PMD, and malignant lesions. Concordance between diagnoses based on clinical examination and those based on histopathological analysis was assessed, and accuracy for the identification of PMD and malignant lesions was calculated. Histopathological analysis revealed 44 lesion types; PMD and malignant lesions comprised 8.3% of all cases. Compared with histopathological analysis, clinical examination showed 97.4% accuracy for the identification of non-malignant and potentially malignant/malignant cases. Degrees of specific sensitivity ranged from 34% to 77% for different lesions, and were highest for autoimmune (77%) and reactive (72%) lesions. Positive and negative predictive values for the identification of PMD and malignant lesions were 81.9% and 98.9%, respectively. Clinical examination showed a high degree of accuracy for the detection of PMD and malignant lip lesions, indicating good reliability.

Long-term ultraviolet flux, other potential risk factors, and skin cancer risk: a cohort study

BACKGROUND

Few prospective studies have examined the relationship between sun exposure, other potential risk factors, and risk of different skin cancers [including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma] simultaneously.

METHODS

We evaluated the association between a number of potential risk factors and skin cancer risk in a cohort of 108,916 US women, the Nurses' Health Study II (1989-2009).

RESULTS

During 2.05 million years of follow-up, we identified 6,955, 880, and 779 diagnoses of BCC, SCC, and melanoma, respectively. Compared with participants in the lowest quintile of cumulative ultraviolet flux in adulthood, participants in the highest quintile had multivariable-adjusted relative risks (RR) of 2.35 (Ptrend < 0.0001) for BCC, 2.53 (Ptrend = 0.009) for SCC, and 0.68 (Ptrend = 0.38) for melanoma. In contrast, the RRs were 1.68 (95% CI, 1.55-1.82) for BCC, 1.68 (95% CI, 1.34-2.11) for SCC, and 1.80 (95% CI, 1.42-2.28) for melanoma for participants with ≥5 blistering sunburns when compared with participants without sunburn between ages 15 and 20 years. We found significant interactions between family history of melanoma, number of blistering sunburns between ages 15 and 20 years and BCC risk, and between sunburn reaction as a child/adolescent and SCC risk (all Pinteraction < 0.05).

CONCLUSION

In a cohort of U.S. women, we found that sun exposures in both early life and adulthood were predictive of BCC and SCC risks, whereas melanoma risk was predominantly associated with sun exposure in early life.

IMPACT

Our results may have potential implications for the prevention of skin cancers. Cancer Epidemiol Biomarkers Prev; 23(6); 1080-9. ©2014 AACR.

Disparities in Uveal Melanoma: Patient Characteristics

Uveal melanoma is the most common intraocular malignancy in adults. Despite excellent rates of local control, half of all patients with uveal melanoma ultimately go on to develop fatal metastatic disease. This review focuses on disparities and differences in the underlying characteristics of the patients, and how these patient characteristics impact the development of metastasis and subsequent patient survival. Specifically, we detail disparities in epidemiology and risk factors as they relate to the development of primary uveal melanoma, to the development of metastasis, and to patient survival following metastasis.

Current Data on Risk Factor Estimates Does Not Explain the Difference in Rates of Melanoma between Hispanics and Non-Hispanic Whites

United States Hispanics have seven times lower melanoma incidence rates than non-Hispanic whites (NHW). It is unclear whether this difference can be explained solely by phenotypic risk factors, like darker skin, or whether modifiable risk factors, like sun exposure, also play a role. The purpose of this paper is to summarize what is currently known about melanoma risk factors among Hispanics and NHWs, and whether or not those differences could explain the difference in melanoma incidence. Through literature review, relative risks and prevalence of melanoma risk factors in Hispanics and NHWs were identified and used to calculate the expected rate in Hispanics and rate ratio compared to NHWs. We found that melanoma risk factors either have similar frequency in Hispanics and NHWs (e.g., many large nevi) or are less frequent in Hispanics but do not explain a high proportion of disease variation (e.g., red hair). Considering current knowledge of risk factor prevalence, we found that melanoma incidence rates in the two groups should actually be similar. Sun exposure behavior among Hispanics may contribute to the explanation for the 7-fold difference in melanoma rates. Currently, limited data exist on sun exposure behavior among Hispanics, but possibilities for improving primary prevention by further studying these practices are substantial.

The role of geographical ecological studies in identifying diseases linked to UVB exposure and/or vitamin D

Using a variety of approaches, researchers have studied the health effects of solar ultraviolet (UV) radiation exposure and vitamin D. This review compares the contributions from geographical ecological studies with those of observational studies and clinical trials. Health outcomes discussed were based on the author's knowledge and include anaphylaxis/food allergy, atopic dermatitis and eczema, attention deficit hyperactivity disorder, autism, back pain, cancer, dental caries, diabetes mellitus type 1, hypertension, inflammatory bowel disease, lupus, mononucleosis, multiple sclerosis, Parkinson disease, pneumonia, rheumatoid arthritis, and sepsis. Important interactions have taken place between study types; sometimes ecological studies were the first to report an inverse correlation between solar UVB doses and health outcomes such as for cancer, leading to both observational studies and clinical trials. In other cases, ecological studies added to the knowledge base. Many ecological studies include other important risk-modifying factors, thereby minimizing the chance of reporting the wrong link. Laboratory studies of mechanisms generally support the role of vitamin D in the outcomes discussed. Indications exist that for some outcomes, UVB effects may be independent of vitamin D. This paper discusses the concept of the ecological fallacy, noting that it applies to all epidemiological studies.

A case-control study of occupational sunlight exposure and renal cancer risk

Epidemiological evidence of a relationship between vitamin D and kidney cancer risk has been inconsistent despite experimental data indicating that vitamin D and its metabolites may inhibit carcinogenesis. Previously we reported an inverse association between renal cell carcinoma (RCC) risk and occupational ultraviolet (UV) exposure among European men. In this study, we examined the association between occupational UV exposure and RCC risk among US residents and investigated whether this association varied by race and sex. Lifetime occupational data for 1,217 RCC cases and 1,235 controls in a population-based case-control study, conducted from 2002 to 2007, were assessed for occupational UV exposure. We evaluated exposure metrics in quartiles based on control exposure levels and calculated associations between RCC risk and occupational UV exposure using unconditional logistic regression adjusted for sex, race, body mass index, smoking, hypertension, center, education, family history of cancer and dietary vitamin D intake. A general pattern of decreasing RCC risk with increasing UV exposure was observed. Cases had significantly lower cumulative occupational UV exposure than controls (fourth quartile vs. first: odds ratio = 0.74 [95% confidence interval = 0.56-0.99], p-trend = 0.03). Similar results were observed for other UV exposure metrics. The association with occupational UV exposure was stronger for women than for men, but did not differ by race. Our findings suggest an inverse association between occupational UV exposure and RCC, particularly among women. Given the sex finding discrepancies in this study versus our previous study, additional research is need to clarify whether the protective effects of occupational UV exposure and RCC risk are real.

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.

Relationship between sun exposure and kidney cancer: preliminary experience with the evaluation of recreational UV exposure

INTRODUCTION

Recent findings reported an inverse relationship between solar ultraviolet-B (UV-B) exposure and mortality from various types of cancers, including renal cancer.

METHODS

We reviewed the literature concerning the relationship between sun exposure and incidence of kidney cancer. We performed a case-control study, evaluating recreational sun exposure in 50 kidney cancer patients and 50 controls.A questionnaire concerning sun exposure habits during childhood, adult life and in the previous 2 years was filled in by every patient. The questionnaire focused on: hours/day spent in the sun during summer; hours/day spent sunbathing (considering as well which kind of UV protection was used); sunburns; holidays in tropical countries.

RESULTS

We found and analyzed few articles concerning the relationship between kidney cancer and sunlight exposure. The two cohorts of patients we evaluated were homogeneous for age, phototype, origin and living area.We found no statistically significant differences between sun exposure in patients affected by kidney cancer and controls, both during childhood and adult life; no differences were found in the use of sunscreens either.

CONCLUSIONS

Recreational sunlight exposure does not differ in our cohorts of patients and controls; studies on greater cohorts are needed to evaluate the effect of recreational sun exposure in the development of kidney cancer.

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.

Association between ultraviolet radiation, skin sun sensitivity and risk of pancreatic cancer

BACKGROUND

Ecological studies showing an inverse association between pancreatic cancer incidence and mortality and levels of ultraviolet radiation (UVR), suggest that higher levels of sun exposure may reduce risks of pancreatic cancer but there has been only one individual-level study that examined this issue. We aimed to examine the association between pancreatic cancer and markers of exposure to solar UVR, namely skin type, treatment of skin lesions, ambient UVR and time outdoors on work days.

METHODS

We used data from an Australian case-control study. Location at birth, residential location during adulthood, outdoors work, history of skin lesion treatment and sensitivity of the skin to the sun were obtained by questionnaire. We limited the analyses to Caucasians who answered the questionnaire about UVR (controls=589/711 recruited; cases=496/705 recruited). We used NASA's Total Ozone Mapping Spectrometer to estimate ambient UVR.

RESULTS

Being born in or living in areas of higher ambient UVR (compared to lower ambient UVR) was associated with about 30-40% lower risk of pancreatic cancer. People with fair skin colour had 47% lower risk of pancreatic cancer than those with dark skin colour (95% CI 0.37-0.75). There was some suggestion of increased risk with increased average number of hours spent outside at work.

CONCLUSIONS

This study suggests that people with light skin colour or those born or living in areas of high ambient UVR have lower risk of pancreatic cancer. Our analysis supports an association between UVR and pancreatic cancer, possibly mediated through production of vitamin D.

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.

Protocol of a randomized controlled trial of sun protection interventions for operating engineers

BACKGROUND

Skin cancer are increasing and some types of skin cancer are among the most lethal cancers yet are easily preventable. However, sun protection interventions are rarely implemented among outdoor workers. Our prior work shows that Michigan Operating Engineers (heavy equipment operators) spend an average of 4-5 hours in the sun, about one-third reported getting sun burned at least once a summer, and over half burned more than once a summer. About three-quarters of the sample never or only sometimes used sun block.

METHODS/DESIGN

Using the Health Belief Model as a guide, this randomized controlled trial (RCT) will test the efficacy of four sun protection interventions targeting Operating Engineers: a) education only; b) education and mailed sunscreen; c) education and text message reminders; and, d) education, mailed sunscreen, and text message reminders. Participations in the study will be offered during regularly scheduled safety trainings at the Local 324 Training Center. Pre- and post-intervention surveys will be collected to determine changes in sunscreen use and sun burning, the primary dependent variables. The analyses will include: a) paired t-tests to determine changes over time (from pre-intervention to post-intervention) in outcome variables (sunscreen use and burning) separately in the 4 intervention groups, b) Repeated Measures Analysis of Variance (RM-ANOVA) to compare the changes in outcomes across the 4 groups, and c) t-tests on change scores as follow-ups to the RM-ANOVA to determine exactly which groups differ from each other.

DISCUSSION

Based on the outcome of this study, we will develop a RO1 for wider scale testing and dissemination in conjunction with the International Training Center which services North America (including the US, Mexico, and Canada). Wide scale dissemination of an efficacious sun protection intervention has the potential to substantially impact skin cancer rates among this population. The ultimate goal is for high reach, high efficacy, and low cost.

TRIAL REGISTRATION

NCT01804595.

Ultraviolet exposure and non-Hodgkin's lymphoma: beneficial and adverse effects?

Studies of risk of non-Hodgkin's lymphoma have found both direct and inverse correlations with respect to solar ultraviolet (UV) doses. Reduced risk is generally found in midlatitudes, while increased risk is generally found at higher latitudes. It is suggested that reduced risk arises from vitamin D production from UVB irradiance, while increased risk arises from immunosuppression associated with UVA irradiance. The ratio of UVA to UVB increases with increasing latitude.

Occupation and work-related ill-health in UK construction workers

BACKGROUND

Construction workers are at increased risk of work-related ill-health (WRI) worldwide.

AIMS

To compare the incidence of medically reported WRI in occupations within the UK construction industry according to job title.

METHODS

We calculated standardized incidence rate ratios (SRRs) using WRI cases for individual job titles returned to The Health and Occupation Reporting network by clinical specialists and UK population denominators. We counted frequencies of reported causal exposures or tasks reported by clinical specialists, occupational physicians and general practitioners.

RESULTS

We found significantly increased incidence of WRI compared with other workers in the same major Standard Occupational Classification, i.e. workers with similar levels of qualifications, training, skills and experience, for skin neoplasia in roofers (SRR 6.3; 95% CI: 3.1-13.1), painters and decorators (2.1; 95% CI: 1.2-3.6) and labourers in building and woodworking trades (labourers, 6.6; 95% CI: 3.2-13.2); contact dermatitis in metal workers (1.4; 95% CI: 1.1-1.7) and labourers (1.6; 95% CI: 1.1-2.3); asthma in welders (3.8; 95% CI: 2.8-5.0); musculoskeletal disorders in welders (1.7; 95% CI: 1.1-2.8), road construction operatives (6.1; 95% CI: 3.8-9.6) and labourers (2.5; 95% CI: 1.7-3.7); long latency respiratory disease (mesothelioma, pneumoconiosis, lung cancer, non-malignant pleural disease) in pipe fitters (4.5; 95% CI: 3.2-6.2), electrical workers (2.7; 95% CI: 2.4-3.2), plumbing and heating engineers (2.3; 95% CI: 1.9-2.7), carpenters and joiners (2.7; 95% CI: 2.3-3.1), scaffolders (12; 95% CI: 8-18) and labourers (3.3; 95% CI: 2.6-4.1).

CONCLUSIONS

UK construction industry workers have significantly increased risk of WRI. These data in individual construction occupations can be used to inform appropriate targeting of occupational health resources.

Health behaviors of Operating Engineers

Operating Engineers (heavy equipment operators in construction) may be at particular risk for heart disease and cancer related to their exposure to environmental dust and smoking, the sedentary nature of their job, and long hours of exposure to the sun. The aim of this study was to characterize the health behaviors of Operating Engineers. This cross-sectional survey from a convenience sample of Operating Engineers (N = 498) used validated instruments to measure smoking, drinking, diet, exercise, sleep, and sun exposure. Univariate and bivariate analyses to detect differences by age were conducted. The sample scored significantly worse on all five health behaviors compared to population norms. Those who were older were less likely to smoke and chew tobacco and more likely to eat fruits and vegetables. Many were interested in services to improve their health behaviors. Health behavior interventions are needed and wanted by Operating Engineers.

Outdoor work and risk for Parkinson's disease: a population-based case-control study

OBJECTIVES

Sunlight is the main contributor to vitamin D in humans. Since inadequate levels of vitamin D have been linked to increased risks for neurodegenerative diseases, we examined whether outdoor work is associated with a reduced risk for Parkinson's disease in a population-based case-control study of Danish men.

METHODS

We identified 3819 men with a primary diagnosis of Parkinson's disease in the period 1995-2006 in the Danish National Hospital Register and selected 19,282 age- and sex-matched population controls at random from the Central Population Register. Information on work history was ascertained from the Danish Supplementary Pension Fund and the Central Population Register. Based on trade grouping codes and job titles, we evaluated the extent of outdoor work of study subjects as a proxy of exposure to sunlight.

RESULTS

Relying on trade grouping codes, we estimated ORs for study subjects with moderate, frequent and maximal outdoor work compared with exclusive indoor work of 0.90 (95% CI 0.78 to 1.02), 0.86 (95% CI 0.75 to 0.99) and 0.72 (95% CI 0.63 to 0.82), respectively, for Parkinson's disease. Reduced risks were also found for Parkinson's disease among outdoor workers based on study subjects' job titles.

CONCLUSIONS

Our findings suggest that men working outdoors have a lower risk for Parkinson's disease. Further studies of measured vitamin D levels in outdoor workers are warranted to clarify a potential inverse association between vitamin D and the risk for Parkinson's disease.

Circulating 25-hydroxyvitamin D and risk of kidney cancer: Cohort Consortium Vitamin D Pooling Project of Rarer Cancers

Although the kidney is a major organ for vitamin D metabolism, activity, and calcium-related homeostasis, little is known about whether this nutrient plays a role in the development or the inhibition of kidney cancer. To address this gap in knowledge, the authors examined the association between circulating 25-hydroxyvitamin D (25(OH)D) and kidney cancer within a large, nested case-control study developed as part of the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers. Concentrations of 25(OH)D were measured from 775 kidney cancer cases and 775 age-, sex-, race-, and season-matched controls from 8 prospective cohort studies. Overall, neither low nor high concentrations of circulating 25(OH)D were significantly associated with kidney cancer risk. Although the data showed a statistically significant decreased risk for females (odds ratio = 0.31, 95% confidence interval: 0.12, 0.85) with 25(OH)D concentrations of > or =75 nmol/L, the linear trend was not statistically significant and the number of cases in this category was small (n = 14). The findings from this consortium-based study do not support the hypothesis that vitamin D is inversely associated with the risk of kidney cancer overall or with renal cell carcinoma specifically.

Occupational sunlight exposure and risk of renal cell carcinoma

BACKGROUND

Recent findings indicate that vitamin D obtained from ultraviolet (UV) exposure may reduce the risk of several different cancers. Vitamin D is metabolized to its active form within the kidney, which is the major organ for vitamin D metabolism and activity. Because both the incidence of renal cell carcinoma (RCC) and the prevalence of vitamin D deficiency have increased over the past few decades, in the current study, the authors explored whether occupational UV exposure was associated with RCC risk.

METHODS

A hospital-based, case-control study of 1097 patients with RCC (cases) and 1476 controls was conducted in 4 Central and Eastern European countries. Demographic and occupational information was collected to examine the association between occupational UV exposure and RCC risk.

RESULTS

A significant reduction (24%-38%) in the risk of RCC was observed with increasing occupational UV exposure among men who participated in the study. No association between UV exposure and RCC risk was observed among women who participated. When the analyses were stratified by latitude as another estimate of sunlight intensity, a stronger reduction (71%-73%) in the risk of RCC was observed between UV exposure and cancer risk among men who resided at the highest latitudes.

CONCLUSIONS

The current results suggested that, among men, there is an inverse association between occupational UV exposure and the risk of RCC. Replication studies are warranted to confirm these results.

Melanocortin 1 receptor (MC1R), pigmentary characteristics and sun exposure: findings from a case-control study of diffuse large B-cell and follicular lymphoma

The relationship between skin cancer and non-Hodgkin lymphoma (NHL) suggests common genetic, host or environmental causes. Ultraviolet radiation (UVR), pigmentary characteristics have been linked with both malignancies, and for skin cancer, the melanocortin 1 receptor (MC1R) which influences pigmentation has also been implicated. This paper reports on the relationship between MC1R, skin, hair and eye colour, time spent outdoors, and diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). Persons carrying MC1R homozygote variant alleles at R151C, R160W, D294H and D84E were more likely to have fair skin, red hair and to spend less time outdoors than those who did not. The variant allele at V92M was associated with FL (odds ratio (OR)=1.61, 95% confidence interval (CI) 1.08-2.39) and the r:wild type genotype with DLBCL (OR=0.58, 95% CI 0.38-0.89). Interactions between MC1R genotypes and skin colour influenced DLBCL risk; the RR genotype increased risk in individuals with medium or dark skin, based on 5 cases and no controls, but decreased risk among those of fair skin. On the whole, DLBCL and FL risk were not related to genetic variation in MC1R, pigmentation or time spent outdoors.

Divergent cancer pathways for early-onset and late-onset cutaneous malignant melanoma

BACKGROUND

Emerging data suggest that cutaneous malignant melanomas (CMM) may arise through divergent cancer pathways that are linked to intermittent versus accumulated sun exposure. However, numerous questions remain regarding the timing and/or age of exposure.

METHODS

The authors systematically examined the effect of aging on CMM incidence in data from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. Standard descriptive epidemiology was supplemented with mathematical models. The impact of advancing age on CMM incidence was assessed by sex, histopathologic classification (superficial spreading melanoma [SSM] or lentigo maligna melanoma [LMM]), and anatomic site (face, head, and neck [FHN] or lower extremity [LE]).

RESULTS

Sex, histopathology, and anatomic site were age-specific effect modifiers for CMM that indicated divergent (bimodal) early-onset and late-onset cancer pathways. Early-onset melanomas were associated predominantly with women, SSM, and LE. Late-onset melanomas were correlated with men, LMM, and FHN. Early- and late-onset melanoma populations were confirmed with age-period-cohort models that were adjusted for period and cohort effects. Two-component mixture models also fit the data better than a single cancer population.

CONCLUSIONS

The current results were consistent with a divergent and age-dependent solar hypothesis for CMM. Early-onset melanomas may represent gene-sun exposure interactions that occur early (and/or intermittently) in life among susceptible individuals. Late-onset melanomas may reflect accumulated, lifelong sun exposure in comparatively less susceptible individuals. Future analytical studies should be powered adequately to account for this age-dependent effect modification both for acknowledged melanoma risk factors (sex, histopathology, and anatomic site) and for suspected melanoma risk factors, such as constituent genetic variants.

Meta-analysis of risk factors for cutaneous melanoma according to anatomical site and clinico-pathological variant

A systematic meta-analysis was performed to evaluate if cutaneous melanoma (CM) risk factors differ depending on body site and histological type. Adjusted estimates were extracted from 24 observational studies, for a total of 16,180 cases. Multivariate random-effects models were used to obtain summary relative risk (RR) estimates for all risk factors by body site and histological type. Summary RRs suggest that high naevus counts are strongly associated with CM on usually not sun exposed sites (p<0.001) while different patterns of sun exposure show a tendency for higher RRs for CM on usually sun exposed sites than on other body sites (p=0.087). Continuous pattern was found to be significantly inversely associated with CM for unexposed sites (p=0.01). RRs also differed by body site for skin (p=0.01) and hair colour (p=0.01), and these differences could be attributed to gene variability. This finding seems to suggest different aetiologic pathways of melanoma development by anatomical site.

The association of cutaneous and iris nevi with uveal melanoma: a meta-analysis

PURPOSE

To study the relationship between cutaneous and iris nevi with uveal melanoma.

DESIGN

Meta-analysis.

METHODS

Three researchers independently searched the literature using Medline from 1966 to August 2007 (with both Ovid and PubMed), EMBASE, MD Consult, and the Web of Science. All bibliographies were searched, and an attempt to contact all primary authors was made to find further unpublished studies.

MAIN OUTCOME MEASURES

Risk factor data were extracted into 4 a priori groups: (1) atypical cutaneous nevi, (2) common cutaneous nevi, (3) cutaneous freckles, and (4) iris nevi.

RESULTS

Meta-analysis of 4 studies (850 cases) examining atypical cutaneous nevi yielded a summary odds ratio (OR) of 2.82 (95% confidence interval [CI], 1.10-7.26; P=0.032). Common cutaneous nevi were reported in 4 studies (825 cases), yielding a summary OR of 1.74 (CI, 1.27-2.39; P=0.001). Cutaneous freckles using 7 studies (2122 cases) found an OR of 1.22 (CI, 1.03-1.45; P=0.022). Iris nevi using 4 studies (825 cases) found an OR of 1.53 (CI, 1.03-2.27; P=0.036). There was no evidence of publication bias for the aforementioned risk factors, with the exception of atypical cutaneous nevi (P=0.03).

CONCLUSIONS

This meta-analysis supports an association between uveal melanoma and atypical cutaneous nevi, common cutaneous nevi, cutaneous freckles, and iris nevi.

Positive interaction between light iris color and ultraviolet radiation in relation to the risk of uveal melanoma: a case-control study

PURPOSE

To examine the association among phenotypic characteristics, chronic and intermittent ultraviolet (UV) radiation, and the risk of uveal melanoma.

DESIGN

Case-control study.

PARTICIPANTS

Overall, between September of 2002 and March of 2005, 1677 eligible subjects (age range: 20-74 years, living in Germany) participated. Interviews were conducted with 459 incident uveal melanoma cases (response proportion 94%), 827 population controls (55%), 180 ophthalmologist controls (52%), and 187 sibling controls (57%).

METHODS

Data on phenotypic characteristics and chronic and intermittent UV radiation exposure were obtained from a self-administered postal questionnaire and computer-assisted telephone interview. We used conditional logistic regression to estimate odds ratios adjusting for the matching factors. Furthermore, we studied the presence of synergy (super additive of risk or relative excess risk due to interaction) between light iris color and several UV radiation exposures.

MAIN OUTCOME MEASURES

Hair color at age 20 years, eye color, untanned skin color, ability to tan, propensity to burn on exposure, freckling, occupational sun exposure, artificial UV radiation, burns to the eyes.

RESULTS

In all 3 control groups, fair skin color, freckling as a child, nevi on the upper arms, burns to the eyes, use of sunlamps, and ever worked outside for 4 or more hours per day were positively associated with uveal melanoma. The association with eye color was apparent only in population controls (odds ratio = 1.9; 95% confidence interval [CI], 1.4-5.2), resulting in a relative excess risk due to interaction of 0.9 (95% CI, -0.6-2.3) for light iris color and more than 5 eye burns (UV-related keratitis) and 0.6 (95% CI, -0.3 to 1.5) for light iris color and eye protection.

CONCLUSIONS

Our interaction analyses suggest that there is an etiologic synergism between light iris color and the exposure of UV radiation. People with light iris color may have an especially increased risk for uveal melanoma if they are exposed to UV radiation.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Cutaneous melanoma and obesity in the Agricultural Health Study

PURPOSE

To describe the risk of cutaneous melanoma in the Agricultural Health Study (AHS), a cohort of pesticide applicators and their spouses, according to baseline characteristics related to obesity along with sun exposure and sun sensitivity.

METHODS

The AHS cohort was enrolled in Iowa and North Carolina during 1993-1997 and followed up through 2003 for cancer incidence. We identified 315 cases of cutaneous melanoma, which reduced to 168 incident cases among subjects reporting height, weight, sun sensitivity, and sun exposure information (on the spouse questionnaire or take-home applicator questionnaire; N = 44,086). Unconditional multiple logistic regression models were used to obtain adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

The results were consistent with those of prior studies of melanoma that indicate an association with measures of sun sensitivity. The highest category of body surface area (BSA; OR = 2.6; 95% CI, 1.5-4.4) and body mass index (BMI; OR = 2.5; 95% CI, 1.5-4.3) at age 20 were significantly associated with melanoma. There was some evidence for an association with BSA, but not BMI, at enrollment.

CONCLUSIONS

Obesity was associated with an increased risk of melanoma, indicating strategies to control obesity may result in risk reduction for melanoma.

Exposure to ultraviolet radiation and risk of malignant lymphoma and multiple myeloma--a multicentre European case-control study

BACKGROUND

Three recent studies have reported a decreased risk of non-Hodgkin lymphoma (NHL) for high ultraviolet (UV) radiation exposure.

METHODS

We conducted a multicentre case-control study during 1998-2004 in France, Germany, Ireland, Italy and Spain, comprising 1518 cases of NHL, 268 cases of Hodgkin lymphoma, 242 cases of multiple myeloma and 2124 population or hospital controls. We collected information on sensitivity to sun and personal exposure to UV radiation in childhood and adulthood via interview, and assessed occupational exposure to UV radiation from the occupational history.

RESULTS

The risk of Hodgkin and NHL was increased for increasing skin sensitivity to the sun [odds ratio (OR) for no suntan vs very brown 2.35, 95% CI 0.94-5.87 and 1.39, 95% CI 1.03-1.87, respectively]. The risk of diffuse large B-cell lymphoma was reduced for increasing adult personal (OR for highest vs lowest quartile of exposure in free days 0.62, 95% CI 0.44-0.87) and for occupational exposure to UV radiation (OR for highest vs lowest exposure tertile 0.63, 95% CI 0.37-1.04). The risk of multiple myeloma was increased for personal exposure to UV radiation during adulthood (OR for highest vs lowest quartile of exposure in free days 1.49, 95% CI 0.88-2.50). A protective effect was observed for use of sun lamps for diffuse large B-cell lymphoma (OR for 25+ times vs never 0.63, 95% CI 0.38-1.03).

CONCLUSIONS

The hypothesis of a protective effect of UV radiation on lymphoma is supported by our results. The underlying mechanisms might differ from those operating in skin carcinogenesis. The increased risk of multiple myeloma is worth replication.