Vitamin D Status and Skin Cancer Risk Independent of Time Outdoors: 11-Year Prospective Study in an Australian Community

Ultraviolet and infrared radiation in Australia: assessing the benefits, risks, and optimal exposure guidelines

Despite extensive research, determining the optimal level of sunlight exposure for human health remains a challenge, emphasizing the need for ongoing scientific inquiry into this critical aspect of human well-being. This review aims to elucidate how different components of the solar spectrum, particularly near-infrared (NIR) radiation and ultraviolet radiation (UVR) affect human health in diverse ways depending on factors such as time of day and duration of exposure. Sunlight has beneficial effects from the production of melatonin by NIR and vitamin D by UVB. Sunlight also causes harmful effects as evidenced by oxidative stress and DNA damage. Exposure to morning and evening sunlight when the UV index is below 3 is suggested to be beneficial for harnessing its positive effects while avoiding the harmful effects of UVR when the UV index is 3 or higher. Understanding the optimal timing and duration of sunlight exposure is crucial for harnessing its beneficial effects while minimizing its harmful consequences by adopting appropriate sun protection measures. By adhering to sun protection guidelines when the UV index is 3 or more and incorporating strategic exposure to NIR rays when the UV index is less than 3, individuals can optimize their health outcomes while mitigating the risks associated with sun exposure. Given that the effects of sun exposure can be both harmful and beneficial, and Australia's unique geographical position where it experiences the highest levels of exposure to sunlight, it is vital to understand the appropriate level and timing of sun exposure to live healthy under the Australian sun.

Epidemiology and Risk Factors of Actinic Keratosis. What is New for The Management for Sun-Damaged Skin

Actinic keratosis (AK) is considered a chronic skin disease mostly caused by long-term exposure to UV radiation and other risk factors such as immunosuppression, leading to an individual susceptibility for skin cancer manifestation. The treatment of AK is laborious and costly, and the incidence of skin cancer is forecasted to double until the year 2030 in an aging society.Risk factors in AK for malignant transformation in cutaneous squamous cell carcinoma (cSCC) are not fully understood, but studies suggest that histological features, such as atypia in the basal epidermal third and basal proliferation (PRO score) in AK play a pivotal role for development of malignancy. As the clinical appearance of AK does not correlate with the risk for malignancy, guidelines suggest treating every single AK lesion upon diagnosis. Skin imaging techniques, such as line-field confocal optical coherence tomography (LC-OCT) can help to provide an individual holistic follow-up for AK lesions by non-invasive visualization of atypia and basal proliferation. A follow-up for patients with AK may be critical for treatment success in terms of strengthening therapy adherence. When AK presents therapy refractory, cSCC manifests in nearly 30% of the cases after several years. Patients with AK suffering from field cancerization and immunosuppression are susceptible for a severe course of disease including metastasis and high mortality rates. Those vulnerable subgroups benefit from close skin cancer screening, early adequate treatment and chemoprevention, such as niacinamide or acitretin. Skin cancer prevention is substantial. Primary prevention should include chemical and physical UV-light protection and avoidance of indoor tanning. Secondary prevention is essential in high-risk populations, such as fair skin type elderly men and STORs. Tertiary prevention should comprise adequate treatment strategies to prevent therapy resistance, reoccurrence and cSCC, especially when field cancerization and immunosuppression are present.

[Translated article] Vitamin D and Skin Cancer: A Controversial Society. Literature Update and Review

Vitamin D (VD) deficiency has been associated with various tumors. However, the association between VD and skin cancer is controversial. Although in non-melanoma skin cancer, adequate or even high levels of VD can be associated with a higher risk of developing tumors, this could be biased by the direct association between sun exposure and VD levels. Regarding melanoma, results are contradictory. Most studies analyzed state that higher levels of VD could reduce the risk of melanoma, be associated with melanomas with better prognosis and with an enhanced antitumor response, and also with fewer adverse events associated with melanoma immunotherapy. However, prospective studies of adequate methodological quality are still needed to assess the association between VD levels and its supplementation and development/prognosis in skin cancer.

Vitamin D and Skin Cancer: A Controversial Society. Literature Update and Review

Vitamin D (VD) deficiency has been associated with various tumors. However, the association between VD and skin cancer is controversial. Although in non-melanoma skin cancer, adequate or even high levels of VD can be associated with a higher risk of developing tumors, this could be biased by the direct association between sun exposure and VD levels. Regarding melanoma, results are contradictory. Most studies analyzed state that higher levels of VD could reduce the risk of melanoma, be associated with melanomas with better prognosis and with an enhanced antitumor response, and also with fewer adverse events associated with melanoma immunotherapy. However, prospective studies of adequate methodological quality are still needed to assess the association between VD levels and its supplementation and development/prognosis in skin cancer.

Vitamin D and potential effects on cancers: a review

Cancer is characterized by the abnormal and uncontrollable division and growth of cells that can infiltrate tissues and alter normal physiological function, which will become crucial and life-threatening if left untreated. Cancer can be a result of genetics, such as mutations or environmental causes, including smoking, lack of physical activity, as well as nutritional imbalance in the body. Vitamin D is one of the foremost nutrients that play a crucial role in a variety of biochemical pathways, and it is an important key factor in several diseases. Vitamin D is an essential nutrient for preventing malignancies and a complementary treatment for cancer through direct and indirect biochemical pathways. In this article, we summarized the correlation between vitamin D and various cancers using an extensive search on PubMed, Google Scholar, and Scopus. This paper reviews the role of vitamin D in different types of cancer.

Circulating vitamin D concentration and risk of 14 cancers: a bidirectional Mendelian randomization study

BACKGROUND

Observational studies have revealed relationships between circulating vitamin D concentrations and the risk of different types of cancer, although the potential causal relationship remains controversial. This study aims to investigate the presence of a causal relationship between circulating vitamin D concentrations and the risk of different types of cancer.

METHODS

Summary statistics from corresponding genome-wide association studies (GWASs) were used to investigate the causal relationship between circulating vitamin D concentrations and the risk of 14 cancers. A two-sample Mendelian randomization (MR) analysis using inverse-variance weighting (IVW) as the primary method was performed. Additionally, the results were verified using four other methods, including MR-Egger, weighted median, weighted mode, and simple mode. Multiple sensitivity analyses were conducted to ensure the robustness of our MR findings.

RESULTS

The MR analysis showed no causal relationship between circulating vitamin D concentrations and most types of cancer, except for a causal relationship with melanoma skin cancer (MSC) (odds ratio [OR]IVW = 1.003, 95% confidence intervals [CI] 1.001-1.005, P = 0.004). Conversely, reverse MR revealed a causal relationship between circulating vitamin D concentration and colorectal cancer (ORIVW = 0.398, 95% CI 0.195-0.813, P = 0.01; ORweighted median = 0.352, 95% CI 0.135-0.917, P = 0.03).

CONCLUSIONS

Our findings provide support for a causal relationship between circulating vitamin D concentration and risk of MSC. Additionally, we found a causal relationship between circulating vitamin D concentration and risk of colorectal cancer in reverse-MR analysis. This evidence indicate that vitamin D is of great significance in the prevention and treatment of MSC and the prognosis of colorectal cancer.

Systemic Photoprotection in Melanoma and Non-Melanoma Skin Cancer

Non-melanoma skin cancers (NMSCs), which include basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and actinic keratosis (AK), are the most common cancer diseases in the Caucasian race. If diagnosed late and improperly treated, BCC and SCC can become locally advanced and metastasize. Malignant melanoma (MM) is less frequent but more lethal than NMSC. Given the individual and social burdens of skin cancers, performing an adequate prevention is needed. Ultraviolet (UV) ray exposure is one of the main risk factors for skin cancer. Thus, the first-choice prevention strategy is represented by photoprotection that can be both topical and systemic. The latter consists of the oral administration of molecules which protect human skin against the damaging effects of UV rays, acting through antioxidant, anti-inflammatory, or immunomodulator mechanisms. Although several compounds are commonly used for photoprotection, only a few molecules have demonstrated their effectiveness in clinical trials and have been included in international guidelines for NMSC prevention (i.e., nicotinamide and retinoids). Moreover, none of them have been demonstrated as able to prevent MM. Clinical and preclinical data regarding the most common compounds used for systemic photoprotection are reported in this review, with a focus on the main mechanisms involved in their photoprotective properties.

To identify the association between dietary vitamin D intake and serum levels and risk or prognostic factors for melanoma-systematic review and meta-analysis

OBJECTIVE

To evaluate the association of serum vitamin D levels and dietary intake with melanoma risk and prognostic factors.

METHODS

Two independent investigators systematically searched PubMed, Embase and ISI Web of Knowledge (Thomson Scientific Technical Support, New York) databases for eligible studies published between January 1992 and September 2020 using the following combinations of search terms: (vitamin D, or 25-hydroxyvitamin D) AND (melanoma, malignant melanoma, cutaneous melanoma, or cutaneous malignant melanoma). Articles not written in English but with English titles and abstracts were also checked. We obtained the full text of all potentially eligible articles, and reference lists of all studies retrieved at the first stage were also checked to identify other eligible papers. Review articles not reporting original data were excluded, but their reference lists were inspected.

RESULTS

Six studies including 212 723 cases reported the association between dietary intake of 25(OH) D serum levels and melanoma risk. The total relative risk for the comparison between the highest and lowest quantiles of the distribution of vitamin D intake was 1.10 (95% CI 0.96 to 1.26) with I ²=56%. Another six studies including 12 297 cases evaluated the association between serum vitamin D levels and melanoma risk. The total relative risk for the comparison of serum vitamin D levels between the highest and lowest quantiles was 1.12 (95% CI 0.53 to 2.35) with I ²=91%. Four studies with 2105 cases investigated the association between serum 25(OH)D (nmol/L) and Breslow thickness, three of which found an inverse association between serum 25(OH)D (nmol/L) and melanoma thickness.

CONCLUSIONS

Vitamin D intake and serum 25(OH)D levels were not closely related with melanoma risk, but an inverse association between serum 25(OH)D levels with melanoma thickness was discovered. As the positive correlation between melanoma thickness and melanoma mortality has been recognised, hence it is concluded that a moderate dietary vitamin D supplement to avoid the serum 25(OH)D deficient might be beneficial to the long-term survival of patients with melanoma.

Vitamin D deficiency in melanoma patients is associated with worse overall survival: a retrospective cohort study

Recent interest has emerged in the protective role of vitamin D in melanoma survival and is the subject of multiple studies with heterogeneous results. Here, we present a retrospective cohort study of 264 patients with invasive melanoma from a tertiary university hospital. The aim of the study was to analyze the relationship between vitamin D levels and prognosis of melanoma patients. We found that lower vitamin D levels are independently associated with worse overall survival in melanoma patients in concordance with previous studies on other populations. Vitamin D deficiency could play a survival role in melanoma patients,. Future prospective studies are needed to investigate the effect of vitamin D supplementation on melanoma outcomes.

Nutrition and nonmelanoma skin cancers

Nonmelanoma skin cancer (NMSC), the most widely diagnosed cancer in the United States, is rising in incidence despite public health and educational campaigns that highlight the importance of sun avoidance. It is,therefore, important to establish other modifiable risk factors that may be contributing to this increase. There is a growing body of evidence in the literature suggesting certain nutrients may have protective or harmful effects on NMSC. We review the current literature on nutrition and its effect on NMSC with a focus on dietary fat, vitamin A, nicotinamide, folate, vitamin C, vitamin D, vitamin E, polyphenols, and selenium.

Vitamin D serum levels and non-melanoma skin cancer risk

Background

Skin cancer is one of the common malignancies. There is sufficient evidence that sunlight (ultraviolet radiation) contributes to the development of skin cancer, but there is also evidence that relates adequate serum levels of vitamin D produced on the skin by the action of ultraviolet radiation with the decreased risk of various types of cancers, including skin cancer. The aim of this study was to investigate the association of vitamin D serum levels among patients with non-melanoma skin cancers (basal cell carcinoma and squamous cell carcinoma) and controls.

Methods

A prospective observational case-control study was conducted in a sample of 84 subjects in Extremadura (Spain). Forty-one patients with histologically diagnosed basal cell carcinomas and squamous cell carcinomas and 43 healthy controls were randomly chosen to assess whether vitamin D (25(OH)D₃) serum level, age and sex were related to non-melanoma skin cancer and to determine the possible risk of this type of skin cancer for these variables.

Results

When analysing serum vitamin D levels, we ensured that all our subjects, both cases and controls, had normal or low serum vitamin D levels, even though the samples were taken during months with the highest solar irradiance in our region. It is striking in our results that there was a higher percentage of subjects with deficits of vitamin D who did not have skin cancer (66%) than patients with deficits with these types of skin cancers (34%). When adjusting the model for age and sex, vitamin D values above 18 ng/ml increased the risk of suffering from non-melanoma skin cancer by nearly 7-fold (aOR: 6.94, 95% CI [1.55-31.11], p = 0.01).

Conclusions

Despite the controversial data obtained in the literature, our results suggest that lower levels of vitamin D may be related to a reduced incidence of non-melanoma skin cancer.

Vitamin D and the Risk of Non-Melanoma Skin Cancer: A Systematic Literature Review and Meta-Analysis on Behalf of the Italian Melanoma Intergroup

Simple Summary

Vitamin D has been extensively studied in relation to cancer risk at several body sites, but its relationship with non-melanoma skin cancer (NMSC), the most frequent malignancy in humans, is still unclear. Here, we performed a systematic literature search and meta-analysis of published studies and did not find convincing evidence that a causal association exists between vitamin D intake (from foods and supplements), vitamin D blood concentration, or polymorphisms of the genes coding for the vitamin D receptor and binding protein, and NMSC risk.

Abstract

We aimed to provide a comprehensive overview of the link between vitamin D and non-melanoma skin cancer (NMSC). For this purpose, we conducted a systematic literature review (updated to 3 February 2021) and meta-analysis of the studies reporting on the association between vitamin D intake (from diet and supplements) and blood concentration, polymorphisms of the vitamin D receptor (VDR) and vitamin D binding protein (VDBP) genes, and the risk of NMSC. Random effects meta-analysis models were fitted to merge study-specific risk estimates into summary relative risk (SRR) and corresponding 95% confidence intervals (CI). Twenty-four studies altogether were included. There was a suggestive association between increasing serum/plasma vitamin D concentration and NMSC risk (SRR for highest vs. lowest concentration 1.67, 95%CI 0.61–4.56), although with large heterogeneity across studies (I² = 91%). NMSC risk was associated with highest vitamin D intake in observational studies but not in clinical trials. Finally, there was no significant association between any polymorphism of the VDR and VDBP genes and NMSC risk. In conclusion, no strong relationship between vitamin D metabolism and NMSC risk appears to exist according to our systematic review and meta-analysis, although some findings are worthy of further investigation.

Can Optimum Solar Radiation Exposure or Supplemented Vitamin D Intake Reduce the Severity of COVID-19 Symptoms?

The foremost mortality-causing symptom associated with COVID-19 is acute respiratory distress syndrome (ARDS). A significant correlation has been identified between the deficiency in vitamin D and the risk of developing ARDS. It has been suggested that if we can reduce or modify ARDS in COVID-19 patients, we may significantly reduce the severity of COVID-19 symptoms and associated mortality rates. The increased mortality of dark-skinned people, who have a reduced UV absorption capacity, may be consistent with diminished vitamin D status. The factors associated with COVID-19 mortality, such as old age, ethnicity, obesity, hypertension, cardiovascular diseases, and diabetes, are all found to be linked with vitamin D deficiency. Based on this review and as a precautionary measure, it is suggested that the adoption of appropriate and safe solar exposure and vitamin D enriched foods and supplements should be considered to reduce the possible severity of COVID-19 symptoms. Safe sun exposure is deemed beneficial globally, specifically in low and middle-income countries, as there is no cost involved. It is also noted that improved solar exposure and vitamin D levels can reduce the impact of other diseases as well, thus assisting in maintaining general human well-being.

Vitamin D Receptor Polymorphisms and Non-Melanoma Skin Cancer Risk: A Case-Control Study

Exposure to sunlight is the major source of vitamin D and the main environmental cause of non-melanocytic skin cancers. Vitamin D, partly mediated through the vitamin D receptor (VDR), has potential therapeutic applications in skin cancer. The aim of this study was to investigate the association of BsmI and ApaI VDR polymorphisms among patients with non-melanoma cancers and controls. An observational case-control study was conducted in a sample of 154 subjects. We observed no significant effects between these polymorphisms and skin cancer risk. When stratified for gender, GG and AG BsmI polymorphisms significantly increased the risk of basal cell carcinomas in males. In relation to ApaI, all three polymorphisms significantly increased the risk of basal cell carcinoma in males. When stratified for age, we found that being 70 years of age or younger was a protective factor against both skin cancers. Being a female and 70 years old or younger was a protective factor for basal cell carcinoma. A comparison of the frequencies of the VDR genotypes in patients older than 70 years vs. 70 years or younger also revealed age-dependent variations in patients with non-melanoma skin cancer. Our study suggests a role for VDR polymorphisms in non-melanoma skin cancer development.

Prediagnostic serum 25-hydroxyvitamin D and melanoma risk

Previous studies of serum 25-hydroxyvitamin D (25(OH)D) in relation to melanoma have shown conflicting results. We conducted a nested case-control study of 708 cases and 708 controls, using prediagnostically collected serum, to study 25(OH)D and melanoma risk in the population-based Janus Serum Bank Cohort. Stratified Cox regression was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for ultraviolet radiation (UVR) indicators and stratified by ambient UVB of residence and body mass index (BMI). Non-linear associations were studied by restricted cubic splines. Missing data were handled with multiple imputation by chained equations. We found an HR of melanoma risk of 1.01 (95% CI: 0.99, 1.04) and an HRimputed of 1.02 (95% CI: 1.00, 1.04) per 5-nmol/L increase. The spline model showed exposure-risk curves with significantly reduced melanoma risk between 60 and 85 nmol/L 25(OH)D (reference 50 nmol/L). Non-significant J-shaped curves were found in sub-analyses of subjects with high ambient UVB of residence and of subjects with BMI < 25 kg/m2. Our data did not yield persuasive evidence for an association between 25(OH)D and melanoma risk overall. Serum levels within the medium range might be associated with reduced risk, an association possibly mediated by BMI.

25-Hydroxyvitamin D status, vitamin D intake, and skin cancer risk: a systematic review and dose-response meta-analysis of prospective studies

Sun exposure is a major environmental risk factor for skin cancers and is also an important source of vitamin D. However, while experimental evidence suggests that vitamin D may have a protective effect on skin cancer risk, epidemiologic studies investigating the influence of 25-hydroxyvitamin D (25(OH)D) level and/or vitamin D intake on skin cancer risk are conflicting. A systematic review and dose–response meta-analyses of prospective studies was conducted to clarify these associations. Relevant studies were identified by searching the PubMed database up to 30th August 2019. Random effects dose–response meta-analyses were used to estimate summary relative risks (SRRs) and 95% confidence intervals (CIs). Overall, thirteen prospective studies were included. Circulating level of 25(OH)D was associated with higher risks of melanoma (SRR (95% CI) per 30 nmol = 1.42 (1.17–1.72)) and keratinocyte cancer (KC) (SRR (95% CI) per 30 nmol/L = 1.30 (1.13–1.49)). The SRR (95% CI) per 30 nmol/L increase in 25(OH) D level was 1.41 (1.19–1.67), and 1.57 (0.64–3.86), for basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs), respectively. However, while we found that vitamin D intake (from diet, supplemental and total) was not associated with risks of melanoma and SCC, vitamin D intake was associated with slightly increased BCC risk, albeit with no heterogeneity across skin cancer type. This meta-analysis suggests positive associations between circulating 25(OH)D level and risk of melanoma and KC, however, this finding is most likely confounded by sun exposure. We found no associations between vitamin D intake skin cancers, except positive associations with BCC risk.

Exploring vitamin D signalling within skin cancer

Sunlight exposure of the skin is associated with both risks and benefits. On one hand, sunlight ultraviolet (UV) radiation can cause skin cancer through signature DNA mutations. On the other hand, it can be absorbed in the skin by 7-dehydrocholesterol to instigate endogenous synthesis of vitamin D to regulate anticancer effects. Thus, protecting one's skin from sunlight to avoid skin cancer may lead to impaired vitamin D levels arguing for sensible sun exposure practices. To limit cancer, vitamin D metabolites can promote uncharacterized and diverse sets of events such as repair responses to DNA damage, apoptosis of malignant cells, and suppression of immune surveillance, proliferation and angiogenesis. Recent findings also suggest that part of the anticancer effects of vitamin D within squamous cell carcinoma-a type of skin cancer most directly linked to sun exposure-involves the DDIT4-mTOR catabolic signalling pathway to enhance cell autophagy. As mTOR activity and cellular metabolism are modulated as part of the DNA damage response, insights into the means by which mTOR can be controlled by vitamin D to suppress cancer is of molecular and clinical importance. Overall, the research so far suggests that presence of vitamin D through sunlight exposure and supplementation are beneficial for human health in the face of cancer.

The association between serum vitamin D level and risk and prognosis of melanoma: a systematic review and meta-analysis

BACKGROUND

Vitamin D has antineoplastic effects, but the synthesis of vitamin D requires ultraviolet radiation, a known risk factor for melanoma.

OBJECTIVE

To investigate the correlations between serum vitamin D levels and risk and prognosis of melanoma.

METHODS

A systematic review and meta-analysis were conducted. Online databases were searched on 31 Oct 2018.

RESULTS

Twenty-five studies with a total of 11166 patients with melanoma were included. There was no significant difference in serum vitamin D levels between patients with melanoma and controls [standardized mean difference (SMD), -0.185; 95% confidence interval (CI), -0.533 to 0.162]. However, the prevalence of vitamin D deficiency was significantly higher in patients with melanoma than that in controls (odds ratio, 2.115; 95% CI, 1.151-3.885). In terms of prognosis, serum vitamin D levels were significantly higher in melanoma patients with lower Breslow thickness (≦1 vs. >1 mm: SMD, 0.243; 95% CI, 0.160-0.327). Moreover, melanoma patients with lower vitamin D levels had a significantly higher mortality rate (hazard ratio, 1.558; 95% CI, 1.258-1.931).

CONCLUSIONS

Vitamin D deficiency is associated with higher Breslow thickness and mortality in melanoma patients.

Relationship Between Level of Serum 25-Hydroxyvitamin D and Risk of Squamous Cell Carcinoma in an Iranian Population

Background

The relationship between vitamin D and skin squamous cell carcinoma (SCC) is not well defined.

Objective

To investigate the relationship between vitamin D levels and the incidence of skin SCC for the first time in Iran.

Methods and Study Design

In this case-control study, 126 subjects were enrolled (63 in each group) out of referents to Razi Skin Hospital in Tehran in 2014. The risk factors for cancer gathered by self-reported questionnaires and blood samples were obtained to measure the level of 25-hydroxyvitamin D. Multivariate logistic regression was used to neutralize the effect of confounding factors.

Results

Cases of SCC were more likely to be in men, older than 49 years and working in an outdoor environment, and with longtime exposure to sunlight and a personal history of skin cancers. Family history of skin cancer and of cigarette smoking were not significantly related to SCC. In the SCC and control groups, 69.8% and 31.7%, respectively, had sufficient levels of vitamin D (P < 0.001). Mean level of 25-hydroxyvitamin D was 40.99 ng/mL in the SCC group and 26.34 ng/mL in the control group (P < 0.05). In the unadjusted model, the level of vitamin D as a continuous variable was positively related to SCC risk. In the adjusted model, vitamin D did not independently predict the likelihood of SCC.

Conclusion

Vitamin D level and SCC risk are directly related, although not in an independent fashion. Indeed, this relation is severely confounded by exposure to sunlight, which was evidenced by an increased vitamin D level in the people working outside and the higher prevalence of SCC in the same population.

Is there a causal relationship between vitamin D and melanoma risk? A Mendelian randomization study

BACKGROUND

Several preclinical studies have identified the antiproliferative effects of 25-hydroxyvitamin D [25(OH)D; vitamin D]. Ultraviolet radiation (UVR) is essential for vitamin D synthesis yet increases the risk of melanoma. Observational studies on the association of vitamin D levels with melanoma risk have reported inconclusive results, and are difficult to interpret owing to the potential confounding from the dual role of UVR.

OBJECTIVES

To determine whether there is a causal association between genetically predicted 25(OH)D concentrations and melanoma using a Mendelian randomization (MR) approach.

METHODS

We performed MR using summary data from a large genome-wide association study (GWAS) meta-analysis of melanoma risk, consisting of 12 874 cases and 23 203 controls. Five single nucleotide polymorphisms associated with 25(OH)D concentration - rs12785878, rs10741657, rs2282679, rs6013897 and rs116970203 - were selected as instrumental variables. An inverse variance weighted method was used to access the evidence for causality. MR results from the melanoma meta-analysis were combined with results from an MR study based on a melanoma risk GWAS using UK Biobank data.

RESULTS

A 20 nmol L^-1 decrease in 25(OH)D was not associated with melanoma risk [odds ratio (OR) 1·06, 95% confidence interval (CI) 0·95-1·19]. Results from the UK Biobank were concordant with this, with meta-analysis of our and UK Biobank-derived MR causal estimates showing no association (OR 1·02, 95% CI 0·92-1·13 for a 20 nmol L^-1 decrease).

CONCLUSIONS

The results suggest that vitamin D levels may not be causally associated with the risk of melanoma. What's already known about this topic? Antitumour activity of vitamin D has been identified in preclinical studies. Observational studies link vitamin D deficiency with an increased risk of a range of cancers. There is a growing public interest for vitamin D supplementation. Observational studies of melanoma are fraught with difficulties because while higher ultraviolet radiation levels increase vitamin D levels, such exposure is also associated with increased melanoma risk. Results from observational studies are inconclusive regarding the effect of vitamin D on melanoma risk. What does this study add? Using Mendelian randomization, an approach to causal inference, which is analogous to a natural randomized controlled trial, we found no causal association between vitamin D levels and melanoma.

25-Hydroxyvitamin D serum levels and melanoma risk: a case-control study and evidence synthesis of clinical epidemiological studies

There is accumulating evidence that the vitamin D pathway may play a role in melanoma. The aim of this study was to investigate the association between 25-hydroxyvitamin D [25(OH)D] serum levels and the risk of cutaneous melanoma. A case-control study with 137 incident cases of melanoma (serum samples collected at the time of diagnosis) and 99 healthy controls (serum samples collected between October and April) was carried out and evaluated in the framework of an evidence synthesis of clinical epidemiological studies on the topic to facilitate comparisons and summarize the scientific evidence produced so far. There was a statistically significant difference in the median levels of serum vitamin D between melanoma patients and healthy controls (18.0 vs. 27.8 ng/ml, P<0.001). Among melanoma patients, 66.2%, compared with 15.2% of healthy controls, had vitamin D deficiency (≤20 ng/ml), whereas vitamin D sufficiency (≥30 ng/ml) was observed in only 7.4% of melanoma patients and in 37.4% of the healthy controls (P<0.001). A multivariate model including age, sex, and BMI showed a statistically significant inverse association between melanoma and vitamin D sufficiency versus deficiency (odds ratio=0.04; 95% confidence interval: 0.02-0.10, P<0.001). Also, vitamin D insufficiency versus deficiency was significantly inversely associated with melanoma (odds ratio=0.13; 95% confidence interval: 0.06-0.27, P<0.001). These results suggest that both deficient and insufficient serum levels of vitamin D are associated with melanoma and that a trend seems to be present with a reduced risk of melanoma when vitamin D approaches normal values.

What's New in Melanoma

Melanoma is rapidly evolving because of advances in noninvasive diagnosis, targeted therapies, and improved prognostic methods. This article discusses what is new in melanoma risk factors, prevention, clinical management, and targeted treatment. The incidence continues to increase worldwide, whereas mortality is steadily improving. This trend reinforces the importance of dermatologists comprehensively understanding all aspects of melanoma. Further research is needed to continue making a material impact on outcomes for patients.

Shedding Light on Vitamin D Status and Its Complexities during Pregnancy, Infancy and Childhood: An Australian Perspective

Ensuring that the entire Australian population is Vitamin D sufficient is challenging, given the wide range of latitudes spanned by the country, its multicultural population and highly urbanised lifestyle of the majority of its population. Specific issues related to the unique aspects of vitamin D metabolism during pregnancy and infancy further complicate how best to develop a universally safe and effective public health policy to ensure vitamin D adequacy for all. Furthermore, as Australia is considered a “sunny country”, it does not yet have a national vitamin D food supplementation policy. Rickets remains very uncommon in Australian infants and children, however it has been recognised for decades that infants of newly arrived immigrants remain particularly at risk. Yet vitamin D deficiency rickets is entirely preventable, with the caveat that when rickets occurs in the absence of preexisting risk factors and/or is poorly responsive to adequate treatment, consideration needs to be given to genetic forms of rickets.

An Epidemiological Review of Diet and Cutaneous Malignant Melanoma

Incidence of cutaneous malignant melanoma has continued to rise despite public efforts to promote sun protection behaviors among populations at risk. However, dietary factors may also affect the development of melanoma. In the past few decades, findings from epidemiologic and experimental research have linked consumption of several foods and other nutrients to the risk of melanoma. Caffeine has been associated with a lower risk of melanoma, and citrus fruits and alcohol with increased risk. Associations between polyunsaturated fatty acid, niacin/nicotinamide, folate, and vitamin D with melanoma remain controversial. Diet likely influences melanoma development through several potential mechanisms, such as enhancing UV-induced apoptosis and increasing photosensitivity. We conducted a narrative review to summarize recent epidemiologic studies of diet and melanoma based on published literature. Given the high prevalence of the food items and nutrients covered in this review and the decades-long rising melanoma incidence worldwide, the associations we discuss may have important public health implications in terms of reducing melanoma incidence through dietary modification. Cancer Epidemiol Biomarkers Prev; 27(10); 1115-22. ©2018 AACR.

Vitamin D levels in actinic keratosis: a preliminary study

BACKGROUND

Recent studies that investigated the effect of vitamin D on skin cancer risk have exhibited inconsistent results.

OBJECTIVE

The aim of the study was to evaluate vitamin D status in patients with actinic keratosis.

METHODS

A cross-sectional study was conducted on 31 patients with actinic keratosis and 29 healthy controls. Serum vitamin D levels in the study group were determined by liquid chromatography/tandem mass spectrometry.

RESULTS

Serum 25(OH)D levels in patients with actinic keratosis were significantly higher than those of the healthy controls (P=0.04). Prevalence of 25(OH)D deficiency was significantly higher in the healthy controls (75.9%) compared to the patients with actinic keratosis (54.8%), but the difference was not statistically significant (P= 0.09).

STUDY LIMITATIONS

The cross-sectional design of the study, data on smoking based on patient self-report, and subjects' different dietary habits, which can influence 25(OH)D levels, are the study's limitations.

CONCLUSION

Serum vitamin D level can be used as a marker for ultraviolet B radiation from sun exposure; therefore, it can be used in individuals at risk of actinic keratosis. Oral intake of vitamin D through diet or supplements is proposed instead of prolonged ultraviolet exposure to maintain adequate vitamin D serum levels. Further research is needed to elucidate the role of vitamin D in skin carcinogenesis.

Preoperative short course radiotherapy with concurrent and consolidation chemotherapies followed by delayed surgery in locally advanced rectal cancer: preliminary results

PURPOSE

This study aimed to assess complications and outcomes of a new approach, that is, combining short course radiotherapy (SRT), concurrent and consolidative chemotherapies, and delayed surgery.

MATERIALS AND METHODS

In this single arm phase II prospective clinical trial, patients with T3-4 or N+ M0 rectal adenocarcinoma were enrolled. Patients who received induction chemotherapy or previous pelvic radiotherapy were excluded. Study protocol consisted of three-dimensional conformal SRT (25 Gy in 5 fractions in 1 week) with concurrent and consolidation chemotherapies including capecitabine and oxaliplatin. Total mesorectal excision was done at least 8 weeks after the last fraction of radiotherapy. Primary outcome was complete pathologic response and secondary outcomes were treatment related complications.

RESULTS

Thirty-three patients completed the planned preoperative chemoradiation and 26 of them underwent surgery (24 low anterior resection and 2 abdominoperineal resection). Acute proctitis grades 2 and 3 were seen in 11 (33.3%) and 7 (21.2%) patients, respectively. There were no grades 3 and 4 subacute hematologic and non-hematologic (genitourinary and peripheral neuropathy) toxicities and perioperative morbidities such as anastomose leakage. Grade 2 or higher late toxicities were observed among 29.6% of the patients. Complete pathologic response was achieved in 8 (30.8%) patients who underwent surgery. The 3-year overall survival and local control rates were 65% and 94%, respectively.

CONCLUSION

This study showed that SRT combined with concurrent and consolidation chemotherapies followed by delayed surgery is not only feasible and tolerable without significant toxicity but also, associated with promising complete pathologic response rates.

Vitamin D deficiency is associated with a worse prognosis in metastatic melanoma

Vitamin D deficiency (≤20 ng/mL) is associated with an increased incidence and worse prognosis of various types of cancer including melanoma. A retrospective, single-center study of individuals diagnosed with melanoma from January 2007 through June 2013 who had a vitamin D (25(OH)D3) level measured within one year of diagnosis was performed to determine whether vitamin D deficiency and repletion are associated with melanoma outcome. A total of 409 individuals diagnosed with histopathology-confirmed melanoma who had an ever measured serum 25(OH)D3 level were identified. 252 individuals with a 25(OH)D3 level recorded within one year after diagnosis were included in the study and the individual and melanoma characteristics such as age, sex, Breslow thickness, ulceration, stage, mitotic rate, and LDH were obtained from the medical record. A worse melanoma prognosis was associated with vitamin D deficiency (P=0.012), higher stage (P<0.001), ulceration (P=0.001), and higher mitotic rate (P=0.001) (HR 1.93, 95% CI 1.15-3.22). In patients with stage IV metastatic melanoma, vitamin D deficiency was associated with significantly worse melanoma-specific mortality (adjusted HR 2.06, 95% CI 1.10-3.87). Patients with metastatic melanoma who were initially vitamin D deficient and subsequently had a decrease or ≤20 ng/mL increase in their 25(OH)D3 concentration had significantly worse outcomes (HR 4.68, 95% CI 1.05-20.88) compared to non-deficient patients who had a >20 ng/mL increase. Our results suggest that initial vitamin D deficiency and insufficient repletion is associated with a worse prognosis in patients with metastatic melanoma.

Vitamin D: An overview

The role of Vitamin D is examined in skin with regards to synthesis and neoplasia. Despite its evolving role in bone health undefined benefits with regards to other disease such as neoplasia and skin cancer are under scrutiny. A brief overview is presented with formalised advice to patients regarding skin cancer, and Vitamin D requirements in the clinical setting. Given that weather conditions in Australia and the Mediterranean climates share similarities, some parallels can be drawn from the Australian experience for Europe.

A protocol for prospective studies of 25-hydroxyvitamin D, leptin and body mass index in relation to cutaneous melanoma incidence and survival

INTRODUCTION

The incidence and mortality rates of cutaneous melanoma (CM) are increasing among fair-skinned populations worldwide. Ultraviolet radiation (UVR) is the principal risk factor for CM, but is also the main source of 25-hydroxyvitamin D (25(OH)D), which has been associated with reduced risk and better prognosis of some cancer types. However, both low and high 25(OH)D levels have been associated with increased risk of CM. Obesity as measured by body mass index (BMI) is associated with risk of several cancers and has also been suggested as a risk factor for CM, and may also be related to insufficient 25(OH)D and/or high leptin levels. Moreover, contracting a CM diagnosis has been associated with increased risk of developing second cancer. We aim to study whether low prediagnostic serum levels of 25(OH)D, high prediagnostic levels of BMI and high serum leptin levels influence CM incidence, Breslow thickness and CM mortality, and risk of second cancer and survival after a CM diagnosis.

METHODS AND ANALYSIS

Cohort and nested case-control studies will be carried out using the population-based Janus Serum Bank Cohort (archival prediagnostic sera, BMI, smoking and physical activity), with follow-up from 1972 to 2014. Additional data will be received from the Cancer Registry of Norway, the national Cause of Death Registry, Statistics Norway (education and occupation) and exposure matrices of UVR. Time-to-event regression models will be used to analyse the cohort data, while the nested case-control studies will be analysed by conditional logistic regression. A multilevel approach will be applied when incorporating group-level data.

ETHICS AND DISSEMINATION

The project is approved by the Regional Committee for Medical Research Ethics and is funded by the Norwegian Cancer Society. Results will be published in peer-reviewed journals, at scientific conferences and in the news media.

High serum vitamin D level correlates with better prognostic indicators in primary melanoma: A pilot study

BACKGROUND/OBJECTIVES

Sunlight is a major risk factor for cutaneous melanoma. However, its interaction with melanoma is complex. In particular, vitamin D is a UVB-derived hormone that has been shown to have anti-cancer effects. In this retrospective pilot study we sought to determine an association between the clinicopathological features of melanoma and the patients' corresponding serum vitamin D level.

METHODS

In total, 109 primary melanomas diagnosed between 2001 and 2013 were retrospectively identified from our institutional database with a corresponding 25-hydroxyvitamin D3 level estimated within 6 months of diagnosis. Tumour, clinical (age, sex, tumour location) and pathological (thickness, mitosis, ulceration, Clark level, subtype, metastatic status) parameters were correlated with vitamin D. For statistical analysis, an unpaired Student's t-test and anova was used for categorical variables, and Spearman's correlation for continuous variables.

RESULTS

Vitamin D level was inversely associated with Breslow thickness as a dichotomous, categorical and continuous variable. The association remained significant when controlled for patient's age and sex (P = 0.026). Vitamin D was higher in non-ulcerated tumours compared with ulcerated tumours (P = 0.006) and in tumours with mitotic rate <1/mm² compared with ≥1/mm² (P = 0.036). A significant association was found between vitamin D level and tumour histological subtype (P = 0.019). On subgroup analysis, significant associations were found between superficial spreading melanoma (SSM) and nodular melanoma (P = 0.026), and SSM and acral lentiginous melanoma (P = 0.007).

CONCLUSION

A high vitamin D status may benefit prognosis in patients diagnosed with primary melanoma. A prospective cohort analysis with a large sample and controlled for other vitamin D confounders would validate these findings.

Is UV an etiological factor of acral melanoma?

Ultraviolet (UV) radiation is a major environmental risk factor for melanoma, particularly among Caucasians. However, studies have generated conflicting results on the role of UV exposure in the development of acral melanoma, the most prevalent subtype of melanoma in non-Caucasians. In this review, we analyzed studies that have examined the relationship between acral melanoma and UV and show that acral melanoma has specific epidemiological and genetic characteristics, with a lower frequency or absence of UV-induced features. Therefore, we postulate that UV is probably not involved in the etiology of acral melanoma. However, further epidemiological and laboratory studies are required to fully address this controversial issue, which may lead to a better understanding of the pathogenesis and prevention of acral melanoma.

Vitamin D Intake and Risk of Skin Cancer in US Women and Men

Previous studies suggested a protective effect of vitamin D against skin cancer development. However, epidemiologic studies on orally taken vitamin D and risk of skin cancer (basal cell carcinoma [BCC], squamous cell carcinoma [SCC], and melanoma) are few. We prospectively evaluated whether total, dietary and supplemental vitamin D intake were associated with skin cancer risk based on 63,760 women in the Nurses' Health Study (1984–2010) and 41,530 men in the Health Professionals Follow-up Study (1986–2010). Dietary information on vitamin D intake was assessed every 2 to 4 years during the follow-up and cumulative averaged intake was used. We used Cox proportional hazard models to compute the hazard ratios (HR) and 95% confidence intervals (CI). Pooled HR of cohort-specific results were calculated using a random-effects model. During the follow-up, we documented 20,840 BCC, 2,329 SCC and 1,320 melanoma cases. Vitamin D consumption was not associated with the risk of SCC or melanoma but was modestly positively associated with BCC; the pooled HRs of BCC for extreme quintiles of vitamin D intake were 1.10 (95%CI = 1.05–1.15; P_trend = 0.05) for total vitamin D and 1.13 (95% CI = 1.07 to 1.20; P_trend <0.01) for dietary vitamin D. Stratified analysis according to sun exposure related factors showed similar results. In conclusion, vitamin D intake was positively associated with risk of BCC, while null associations were found with SCC and melanoma. Our data do not support a beneficial role of orally taken vitamin D on skin cancer carcinogenesis.

Mitochondrial and lipogenic effects of vitamin D on differentiating and proliferating human keratinocytes

Even in cells that are resistant to the differentiating effects of vitamin D, the activated vitamin D receptor (VDR) can downregulate the mitochondrial respiratory chain and sustain cell growth through enhancing the activity of biosynthetic pathways. The aim of this study was to investigate whether vitamin D is effective also in modulating mitochondria and biosynthetic metabolism of differentiating cells. We compared the effect of vitamin D on two cellular models: the primary human keratinocytes, differentiating and sensitive to the genomic action of VDR, and the human keratinocyte cell line HaCaT, characterized by a rapid growth and resistance to vitamin D. We analysed the nuclear translocation and features of VDR, the effects of vitamin D on mitochondrial transcription and the consequences on lipid biosynthetic fate. We found that the negative modulation of respiratory chain is a general mechanism of action of vitamin D, but at high doses, the HaCaT cells became resistant to mitochondrial effects by upregulating the catabolic enzyme CYP24 hydroxylase. In differentiating keratinocytes, vitamin D treatment promoted intracellular lipid deposition, likewise the inhibitor of respiratory chain stigmatellin, whereas in proliferating HaCaT, this biosynthetic pathway was not inducible by the hormone. By linking the results on respiratory chain and lipid accumulation, we conclude that vitamin D, by suppressing respiratory chain transcription in all keratinocytes, is able to support both the proliferation and the specialized metabolism of differentiating cells. Through mitochondrial control, vitamin D can have an essential role in all the metabolic phenotypes occurring in healthy and diseased skin.

Pilot study on the bioactivity of vitamin d in the skin after oral supplementation

Laboratory studies suggest that vitamin D (VD) supplementation inhibits skin carcinogenesis. However, epidemiologic studies report mixed findings in the association between circulating VD levels and skin cancer risk. We conducted a clinical study to determine whether oral cholecalciferol supplementation would exert direct bioactivity in human skin through modulation of the VD receptor (VDR). We enrolled 25 individuals with serum 25-hydroxyvitamin-D levels <30 ng/mL and with skin photodamage to take 50,000 IU of cholecalciferol biweekly for 8 to 9 weeks. Then, we obtained baseline and end-of-study skin biopsies from photodamaged (PD) and photoprotected (PP) skin, and from benign nevi (BN) and tested for mRNA expression of VDR and cytochrome P450-24 (CYP24), and markers of keratinocytic differentiation. High-dose cholecalciferol supplementation significantly elevated circulating levels of 25-hydroxyvitamin-D (P < 0.0001) and 1,25-dihydroxyvitamin-D (P < 0.0001). VDR expression in PD- and PP-skin showed minimum changes after supplementation. CYP24 expression in PD- and PP-skin was increased after supplementation by 186%, P = 0.08, and 134%, P = 0.07, respectively. In BNs from 11 participants, a trend for higher VDR and CYP24 expression was observed (average of 20%, P = 0.08, and 544%, P = 0.09, respectively). Caspase-14 expression at the basal layer in PD skin samples was the only epidermal differentiation marker that was significantly increased (49%, P < 0.0001). High-dose cholecalciferol supplementation raised serum VD metabolite levels concurrently with CYP24 mRNA and caspase-14 levels in the skin. Our findings of significant variability in the range of VDR and CYP24 expression across study samples represent an important consideration in studies evaluating the role of VD as a skin cancer chemopreventive agent.

Skin cancer and vitamin D: an update

Exposure of the skin to solar ultraviolet (UV) radiation has both risks and benefits for human health. Absorption of UV-B radiation by DNA results in mutations that underlie the development of skin cancers, as is apparent from genetic studies showing high occurrence of UV signature mutations within these tumors. UV-B radiation is also absorbed by 7-dehydrocholesterol to initiate vitamin D synthesis. In experimental studies vitamin D metabolites enhance apoptosis of malignant cells, inhibit angiogenesis and proliferation and increase differentiation, potentially reducing skin cancer development and improving prognosis after diagnosis. There are some supporting human data. We review the links between sun exposure, vitamin D and skin cancers.

Is a personal history of nonmelanoma skin cancer associated with increased or decreased risk of other cancers?

Two conflicting hypotheses have been tested concerning the association between a personal history of nonmelanoma skin cancer (NMSC) and risk of other malignancies. One hypothesis is that as a marker of extensive sunlight exposure and hence vitamin D status, NMSC should be inversely associated with risk of other cancers. Alternatively, under the multiple primary cancer model, NMSC is postulated to be an informative first cancer to study as a marker of increased risk of subsequent primary cancer diagnoses. In this journal issue, Ong and colleagues report the results of a large-scale study in the United Kingdom with findings that NMSC was significantly associated with increased risk of a broad spectrum of other malignancies, with the associations stronger the younger the age of onset of NMSC. These results are consistent with the larger body of evidence on this topic, which is highly asymmetrical in favor of the multiple primary cancer hypothesis. Two divergent hypotheses have been tested, with the empirical evidence unequivocally indicating that NMSC is a marker of a high cancer risk phenotype. Future research is warranted to better characterize this association, to understand why NMSC is a marker of excess risk of other cancers, and to determine whether this association is clinically relevant.

The consequences for human health of stratospheric ozone depletion in association with other environmental factors

Ozone depletion, climate and human health.

Diet in dermatology: Part II. Melanoma, chronic urticaria, and psoriasis

The roles of dietary factors in aggravating, preventing, or treating skin diseases are common questions encountered in dermatology practice. Part II of this two-part series reviews dietary modifications that can potentially be utilized in the management of melanoma, chronic urticaria, and psoriasis patients. Specifically, we examine the effect of alcohol consumption and supplementation with vitamins D and E, polyunsaturated fatty acids, selenium, green tea, resveratrol, and lycopene on melanoma risk. The relationships between chronic urticaria symptoms and dietary pseudoallergens, gluten, and vitamin D are analyzed. We explore weight loss, reduced alcohol consumption, and gluten avoidance as means of reducing psoriasis-associated morbidity, as well as the possible utility of supplementation with polyunsaturated fatty acids, folic acid, vitamin D, and antioxidants. With proper knowledge of the role of diet in these cutaneous disease processes, dermatologists can better answer patient inquiries and consider implementation of dietary modifications as adjuncts to other treatments and preventative measures.

Vitamin D and melanoma and non-melanoma skin cancer risk and prognosis: a comprehensive review and meta-analysis

Vitamin D is formed mainly in the skin upon exposure to sunlight and can as well be taken orally with food or through supplements. While sun exposure is a known risk factor for skin cancer development, vitamin D exerts anti-proliferative and pro-apoptotic effects on melanocytes and keratinocytes in vitro. To clarify the role of vitamin D in skin carcinogenesis, we performed a review of the literature and meta-analysis to evaluate the association of vitamin D serum levels and dietary intake with cutaneous melanoma (CM) and non-melanoma skin cancer (NMSC) risk and melanoma prognostic factors. Twenty papers were included for an overall 1420 CM and 2317 NMSC. The summary relative risks (SRRs) from random effects models for the association of highest versus lowest vitamin D serum levels was 1.46 (95% confidence interval (CI) 0.60-3.53) and 1.64 (95% CI 1.02-2.65) for CM and NMSC, respectively. The SRR for the highest versus lowest quintile of vitamin D intake was 0.86 (95% CI 0.63-1.13) for CM and 1.03 (95% CI 0.95-1.13) for NMSC. Data were suggestive of an inverse association between vitamin D blood levels and CM thickness at diagnosis. Further research is needed to investigate the effect of vitamin D on skin cancer risk in populations with different exposure to sunlight and dietary habits, and to evaluate whether vitamin D supplementation is effective in improving CM survival.

Sun exposure, sunbeds and sunscreens and melanoma. What are the controversies?

The association between various measures of sun exposure and melanoma risk is quite complex to dissect as many case-control studies of melanoma included different subtypes of melanomas which are likely to be biologically different, so interpretation of the data is difficult. Screening bias in countries with high levels of sun exposure is also an issue. Now that progress is being made in the genetic subclassification of melanoma tumours, it is apparent that melanomas have different somatic changes according to body sites/histological subtypes and that UV exposure may be relevant for some but not all types of melanomas. Melanoma behaviour also points to non-sun-related risk factors, and complex gene-environment interactions are likely. As UV exposure is the only environmental factor ever linked to melanoma, it is still prudent to avoid excessive sun exposure and sunburn especially in poor tanners. However, the impact of strict sun avoidance, which should not be recommended, may take years to be apparent as vitamin D deficiency is a now a common health issue in Caucasian populations, with a significant impact on health in general.

Melanoma-related mortality and productivity losses in the USA, 1990-2008

Melanoma remains among the deadliest cancers in the USA, ranking presently as the leading cause of death from skin disease in this country. The present analysis presents national statistics on the health burden (mortality) and productivity losses attributable to this cancer over a 19-year period. Melanoma-related deaths and mortality rates from 1990 through 2008 were identified and calculated using multiple-cause-of-death data and data from the 2000 US Census. Productivity losses were estimated using previously published methods that accounted for life expectancy, labor force participation, productivity growth, and the imputed values of caregiving and housekeeping activities. A total of 155,571 melanoma-related deaths occurred during 1990-2008, resulting in 1,811,701 years of potential life lost. Age-adjusted mortality rates stratified by sex and race/ethnicity revealed differences: whites had the highest rate (3.55 per 100 000 population; 95% confidence interval 3.54, 3.57) and male individuals were 2.21 times more likely than female individuals to succumb to the disease. Cumulatively, the numbers of death for blacks, Hispanics, Asian/Pacific Islanders, and American Indians/Alaskan Natives exceeded 6000 deaths. The total productivity losses attributable to melanoma-related mortality during the sampled period were ∼$66.9 billion. The burden and economic consequences of melanoma-related deaths in the USA are not inconsequential. Understanding the mortality trends and productivity losses attributed to this skin cancer is important for evaluating the feasibility and trade-offs of public health and behavioral counseling interventions that focus on promoting skin cancer prevention.

Vitamin D level and basal cell carcinoma, squamous cell carcinoma, and melanoma risk

Various associations between serum vitamin D levels and skin cancer have been reported. In this issue, van der Pols et al. observed that baseline 25-hydroxyvitamin D (25OHD) levels above 75 nmol/L were associated with an increased incidence of basal cell carcinoma and melanoma, and a nonstatistically significant decreased incidence of squamous cell carcinoma. Complex factors including sun exposure, skin phototype, and anticarcinogenic and procarcinogenic effects of vitamin D are potential causes of the observed associations.