Obesity and the incidence of skin cancer in US Caucasians

TGF-β, IL-1β, IL-6 levels and TGF-β/Smad pathway reactivity regulate the link between allergic diseases, cancer risk, and metabolic dysregulations

The risk of cancer is higher in patients with asthma compared to those with allergic rhinitis for many types of cancer, except for certain cancers where a contrasting pattern is observed. This study offers a potential explanation for these observations, proposing that the premalignant levels of circulating transforming growth factor-β (TGF-β), IL-1β, and IL-6 as well as the reactivity of the TGF-β/Smad signaling pathway at the specific cancer site, are crucial factors contributing to the observed disparities. Circulating TGF-β, IL- β and IL-6 levels also help clarify why asthma is positively associated with obesity, Type 2 diabetes, hypertension, and insulin resistance, whereas allergic rhinitis is negatively linked to these conditions. Furthermore, TGF-β/Smad pathway reactivity explains the dual impact of obesity, increasing the risk of certain types of cancer while offering protection against other types of cancer. It is suggested that the association of asthma with cancer and metabolic dysregulations is primarily linked to the subtype of neutrophilic asthma. A binary classification of TGF-β activity as either high (in the presence of IL-1β and IL-6) or low (in the presence or absence of IL-1β and IL-6) is proposed to differentiate between allergy patients prone to cancer and metabolic dysregulations and those less prone. Glycolysis and oxidative phosphorylation, the two major metabolic pathways utilized by cells for energy exploitation, potentially underlie this dichotomous classification by reprogramming metabolic pathways in immune cells.

Thiazolidinedione enhances the efficacy of anti-PD-1 monoclonal antibody in murine melanoma

Several clinical studies observed a surprising beneficial effect of obesity on enhancing immunotherapy responsiveness in patients with melanoma, highlighting an as-yet insufficiently understood relationship between metabolism and immunogenicity. Here, we demonstrate that the thiazolidinedione (TZD) rosiglitazone, a drug commonly used to treat diabetes by sequestering fatty acids in metabolically inert subcutaneous adipose tissue, improved sensitivity to anti-programmed cell death protein 1 (PD-1) treatment in YUMMER1.7 tumor-bearing mice, an initially immunotherapy-sensitive murine melanoma model. We observed a transition from high to intermediate PD-1 expression in tumor-infiltrating CD8+ T cells. Moreover, TZD inhibited PD-1 expression in mouse and human T cells treated in vitro. In addition to its direct impact on immune cells, TZD also decreased circulating insulin concentrations, while insulin induced T cell exhaustion in culture. In TZD-treated mice, we observed higher fatty acid concentrations in the tumor microenvironment, with fatty acids protecting against exhaustion in culture. Together, these data are consistent with an indirect mechanism of TZD inhibiting T cell exhaustion. Finally, we analyzed imaging data from patients with melanoma before and after anti-PD-1 treatment, confirming the beneficial effect of increased subcutaneous fat on anti-PD-1 responsiveness in patients. We also found that the expression of peroxisome proliferator-activated receptor gamma (PPARγ), the canonical activator of lipid uptake and adipogenesis activated by TZD, correlated with overall survival time. Taken together, these data identify a new adjuvant to enhance immunotherapy efficacy in YUMMER1.7 melanoma mice, and discover a new metabolism-based prognostic marker in human melanoma.NEW & NOTEWORTHY Zhang et al. demonstrate that the diabetes drug rosiglitazone improves the efficacy of immunotherapy in mouse melanoma. This effect is both direct and indirect: TZD directly reduces PD-1 expression in CD8+ T cells (i.e., reduces exhaustion), and indirectly reduces exhaustion by lowering insulin levels and increasing local fat. Finally, they demonstrate that hallmarks of TZD action (such as PPARγ expression and subcutaneous fat content) correlate with improved immunotherapy efficacy in humans with melanoma.

Evaluating the effect of body mass index and 25-hydroxy-vitamin D level on basal cell carcinoma using Mendelian randomization

Basal cell carcinoma (BCC) is the most common cancer with a rising incidence among white-skinned individuals. A number of epidemiological studies have suggested that obesity and serum 25-hydroxy-vitamin D (25(OH)D) levels may affect the arising of BCC. To address this, we selected 443 and 96 single nucleotide polymorphisms (SNPs) associated with body mass index (BMI) and serum level of 25(OH)D from large-scale genome-wide association studies (GWAS), respectively. The univariable and multivariable two-sample Mendelian randomization (MR) analyses were conducted with a series of sensitivity analyses to ensure the results were reliable and reproducible. The results of univariable two-sample MR analysis showed that higher BMI was related to lower risk for BCC (Odds ratio(OR) = 0.90; 95% confidence interval (CI),[0.81,0.99]; p = 0.02). In addition, this causal effect of BMI on BCC still remained (OR = 0.88; 95%CI,[- 0.22, - 0.03], p-value = 0.008) after adjusting for 25(OH)D level in the multivariable MR analysis. However, the results suggested that 25(OH)D level was not associated with BCC(OR = 1.02; 95%CI, [0.94,1.09], p-value = 0.67). In conclusion, similar to the conclusions of retrospective observational studies, the MR results indicate that high BMI is an independent protective factor for BCC. Meanwhile, vitamin D levels may not be causally associated with the risk of basal cell carcinoma and increasing vitamin D supplementation is unlikely to reduce the risk.

Skin cancer risk of menopausal hormone therapy in a Korean cohort

Conflicting studies exist on the association between menopausal hormone therapy (MHT) and skin cancers, such as melanoma and non-melanoma skin cancer (NMSC). This retrospective cohort study aimed to evaluate the risk of skin cancer from MHT using data from 2002 to 2019 from the National Health Insurance Service in South Korea. We included 192,202 patients with MHT and 494,343 healthy controls. Women > 40 years who had menopause between 2002 and 2011 were included. Patients with MHT had at least one MHT for at least 6 months and healthy controls had never been prescribed MHT agents. We measured the incidence of melanoma and NMSC. Melanoma developed in 70 (0.03%) patients with MHT and 249 (0.05%) controls, while the incidence of NMSC was 417 (0.22%) in the MHT group and 1680 (0.34%) in the controls. Tibolone (hazard ratio [HR] 0.812, 95% confidence interval [CI] 0.694-0.949) and combined oestrogen plus progestin by the manufacturer (COPM; HR 0.777, 95% CI 0.63-0.962) lowered the risk of NMSC, while other hormone groups did not change the risk. Overall, MHT was not associated with melanoma incidence in menopausal Korean women. Instead, tibolone and COPM were associated with a decrease in NMSC occurrence.

Body mass index and the risk of basal cell carcinoma: evidence from Mendelian randomization analysis

Objective

We aim to test whether body mass index (BMI) is causally associated with the risk of basal cell carcinoma (BCC) using Mendelian randomization (MR) analysis.

Methods

Single-nucleotide polymorphisms (SNPs) associated with four BMI-related traits were screened via a genome-wide association study (GWAS) with 681,275, 336,107, 454,884, and 461,460 European-descent individuals, respectively. Summary-level data for BCC (17,416 cases and 375,455 controls) were extracted from UK Biobank. An inverse variance weighted (IVW) method was employed as the primary MR analysis. Sensitivity analyses were conducted via MR-Egger regression, heterogeneity test, pleiotropy test, and leave-one-out sensitivity test. The assumption that exposure causes outcome was verified using the MR Steiger test. Meta-analysis was also used to estimate the average genetically predicted effect of BMI on BCC.

Results

Two-sample MR analysis showed inverse associations between genetically predicted BMI and BCC risk. Moreover, when exposure and outcome were switched to see if reverse causation was possible, there was no evidence of a cause-and-effect relationship from BCC to BMI. Finally, the meta-analysis also showed a strong negative causal relationship between BMI and BCC.

Conclusion

Genetical predicted higher BMI were associated with lower BCC risk. Further research is required to comprehend the mechanisms underlying this putative causative association.

Risk of Melanoma in Patients with Basal Cell Carcinoma: A Population-based Cohort Study

Basal cell carcinoma is the most prevalent cancer in Caucasians worldwide. The aim of this study was to examine the overall risk of melanoma among patients diagnosed with basal cell carcinoma. This population-based retrospective cohort study included data from January 2010 to December 2018 from the databases of the Clalit Health Maintenance Organization and 2 major pathology laboratories in North District, Israel. The incidence and hazard ratio of melanoma in patients with a diagnosis of basal cell carcinoma were determined. Of 466,700 participants, 51% were women and the mean (standard deviation) follow-up was 6.7 (2.9; range 1-9) years. A total of 3,338 patients were diagnosed with basal cell carcinoma during the study period, 82 of whom subsequently developed melanoma. Patients with basal cell carcinoma had a significantly higher incidence of melanoma than patients without basal cell carcinoma (2.46% vs 0.37%; p < 0.0001). Univariate Cox regression analysis revealed a hazard ratio of 6.6 (95% confidence interval: 3.6-12.1; p < 0.0001) for melanoma in patients with a diagnosis of basal cell carcinoma. In conclusion, a diagnosis of basal cell carcinoma confers a significant risk of melanoma.

Frequency of skin cancer and evaluation of risk factors: A hospital-based study from Turkey

OBJECTIVES

Skin cancers are the most common type of cancer with a significantly increasing incidence. The purpose of the study was to uncover the one-year frequency of melanoma and non-melanoma skin cancers (NMSC) and to determine the risk factors in the development of skin cancer.

METHODS

The study included 7396 people from all age groups admitted to the dermatology clinic between October 2020 and 2021. The sociodemographic characteristics, sun protection habits, chronic diseases, and drug and vitamin use were evaluated. Lesions with clinical suspicion of skin cancer were excised.

RESULTS

The frequency of skin cancer was found to be 2.7%, basal cell cancer (BCC) 1.2%, squamous cell cancer (SCC) 1.1%, malignant melanoma (MM) was 0.4%. Daily black tea consumption was found to be a risk factor for three type of skin cancer, BCC (p = 0.021), SCC (p = 0.006), and MM (p = 0.002), respectively. Obesity was observed as a risk factor for BCC (p = 0.005) and MM (p = 0.008). We found that having a history of alcohol use were an independent risk factor for all skin cancer types and BMI <30 for SCC. Vitamin D and supplemental drugs intake were observed as protective factors for BCC (p = 0.035, p = 0.007, respectively). Daily coffee consumption was determined as a protective factor for SCC (p < 0.001) and MM (p = 0.049).

CONCLUSION

This study estimates the frequency of NMSC and melanoma. Also provides evidence to determine the risk factors and probably protective factors for the development of skin cancers.

Skin cancer outcomes and risk factors in renal transplant recipients: Analysis of organ procurement and transplantation network data from 2000 to 2021

Purpose

Posttransplant skin cancer is the most common malignancy after patients have undergone renal transplantation. Through comprehensive observation with a large sample size nationwide, understanding the risk factors and outcome of posttransplant skin cancer will help to develop appropriate patient surveillance and disease prevention strategies.

Materials and methods

This retrospective population-based cohort study was based on Organ Procurement and Transplantation Network data released in March 2021. Characteristics and outcomes, including patient survival and graft survival of recipients, were compared. Risk factors for posttransplant skin cancer, cancer onset momentum, and mortality were determined.

Results

A total of 199,564 renal transplant recipients were included. After renal transplantation, 7,334 (3.68%), 6,093 (3.05%), and 936 (0.47%) were diagnosed with squamous cell carcinoma, basal cell carcinoma, and melanoma, respectively. Skin cancer was the major cause of death (squamous cell carcinoma: 23.8%, basal cell carcinoma: 18%, and melanoma: 41.6%). Five-year survival rates ranked from best to worst were as follows: basal cell carcinoma (96.7 [95% confidence interval: 96.3-97.2]%), squamous cell carcinoma (94.1 [93.5-94.6]%), melanoma (89.7 [87.7-91.6]%), and cancer-free (87.4 [87.2-87.5]%) (p < 0.001 for all except melanoma vs. cancer-free, p = 0.534). Regarding graft survival, death-censored graft survival, posttransplant skin cancer, and melanoma were significantly better than the cancer-free group (p < 0.001). Independent risk factors for developing posttransplant skin cancer included older age, male sex, Caucasian race, pretransplant malignancy, polycystic kidney disease-induced end-stage renal disease (ESRD), retransplantation, private health insurance, T-cell depletion induction, and tacrolimus/mycophenolic acid use. Caucasian race and pretransplant malignancy were independent risk factors for posttransplant skin cancer onset momentum. Male sex, Caucasian race, pretransplant malignancy, hypertension- or diabetes-induced ESRD, retransplantation, diabetes history, deceased donor, cyclosporin, and mTOR inhibitor use were independent risk factors for posttransplant skin cancer mortality.

Conclusion

Although posttransplant skin cancer is a major cause of recipient death, information regarding its impact on patient and graft survival is limited. Given the differences regarding risk factors for posttransplant skin cancer incidence, onset momentum, and mortality, personalized approaches to screening may be appropriate to address the complex issues encountered by kidney transplant recipients.

The role of bariatric and metabolic surgery in the development, diagnosis, and treatment of endometrial cancer

The obesity pandemic continues to contribute to a worsening burden of disease worldwide. The link between obesity and diseases such as diabetes, cardiovascular disease, and cancer has been well established, yet most patients living with obesity remain untreated or undertreated. Metabolic and bariatric surgery is the most effective and durable treatment for obesity, is safe, and may have a protective benefit with respect to cancer incidence. In this review, an overview of the link between obesity, metabolic surgery, and cancer is discussed with emphasis on indications for endometrial cancer, the malignancy most strongly associated with obesity. Considerable evidence from retrospective and prospective cohort studies supports a decreased risk of endometrial cancer in patients with obesity who undergo bariatric surgery compared with nonsurgical controls. Survivors of endometrial cancer are at increased risk of poor health outcomes associated with obesity, and women with endometrial cancer are more likely to die of cardiovascular disease and other obesity-related illnesses than of the malignancy itself. Recent advances in anticancer drug therapies have targeted pathways that may also be therapeutically altered with metabolic surgery. Metabolic surgery has significant potential to enter the treatment paradigm for endometrial cancer, and gynecologic oncologist visits present an opportunity to identify patients who may benefit the most.

Novel insights into the consequences of obesity: a phenotype-wide Mendelian randomization study

Obesity is thought to significantly impact the quality of life. In this study, we sought to evaluate the health consequences of obesity on the risk of a broad spectrum of human diseases. The causal effects of exposing to obesity on health outcomes were inferred using Mendelian randomization (MR) analyses using a fixed effects inverse-variance weighted model. The instrumental variables were SNPs associated with obesity as measured by body mass index (BMI) reported by GIANT consortium. The spectrum of outcome consisted of the phenotypes from published GWAS and the UK Biobank. The MR-Egger intercept test was applied to estimate horizontal pleiotropic effects, along with Cochran's Q test to assess heterogeneity among the causal effects of instrumental variables. Our MR results confirmed many putative disease risks due to obesity, such as diabetes, dyslipidemia, sleep disorder, gout, smoking behaviors, arthritis, myocardial infarction, and diabetes-related eye disease. The novel findings indicated that elevated red blood cell count was inferred as a mediator of BMI-induced type 2 diabetes in our bidirectional MR analysis. Intriguingly, the effects that higher BMI could decrease the risk of both skin and prostate cancers, reduce calorie intake, and increase the portion size warrant further studies. Our results shed light on a novel mechanism of the disease-causing roles of obesity.

COX-2 inhibitors show no preventive effect in the development of skin cancer

BACKGROUND

Some clinical trials found that cyclooxygenase-2 (COX-2) inhibitor use lowered the risk of skin cancer in high-risk groups.

PATIENTS AND METHODS

To determine whether COX-2 inhibitor use is associated with lower risk of basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC), and melanoma, we analyzed COX-2 inhibitor use and risk of skin cancer based on three prospective cohort studies, the Nurses' Health Study (NHS), NHS II, and the Health Professionals Follow-up Study, including 153,882 participants. Multivariable hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association of COX-2 inhibitor use with risk of BCC, cSCC, and melanoma were estimated using Cox proportional hazards models. We pooled the results using a fixed effects model.

RESULTS

16,142 BCC, 1,973 cSCC, and 631 melanoma cases were documented. Ever vs. never use of COX-2 inhibitor was associated with a modestly increased risk of BCC (multivariable HR 1.09, 95 % CI 1.05-1.14). The hazard ratio was similar for cSCC (multivariable HR 1.12, 95 % CI 1.00-1.27) and melanoma (multivariable HR 1.10, 95 % CI 0.89-1.38), but was not statistically significant.

CONCLUSIONS

Ever use of COX-2 inhibitor was not associated with a decreased skin cancer risk but was instead associated with a modest, increased risk of BCC.

Possible Role of Leptin in Atopic Dermatitis: A Literature Review

Atopic dermatitis (AD) is the most frequent chronic inflammatory skin disease, and its incidence has been rapidly increasing in developed countries in the last years. AD presents a high degree of heterogeneity due to biases and confounding factors such as age range, sex, or ethnicity. For those reasons, the search for new biomarkers is crucial. At the same time, obesity, which is a global health problem, has also increased over the years. It has been associated with many pathophysiological states, including skin diseases such as AD, mostly in childhood. Obesity promotes a low grade inflammation driven by many different cytokines and adipokines, including leptin, which has a key role in many other diseases due to its pleiotropic effects. Leptin also has a role in both skin and allergic diseases very related to AD. Thus, this adipokine could have an important role in the pathogenesis of AD, especially in its chronicity. Despite the limited literature available, there is some evidence that leads us to consider leptin as an important adipokine in this skin disease. For this reason, here we have reviewed the role of leptin in the pathophysiology of AD.

Ultraviolet Radiation and Basal Cell Carcinoma: An Environmental Perspective

Ultraviolet radiation (UVR) is a known carcinogen participated for the development of skin cancers. Solar UVR exposure, particularly ultraviolet B (UVB), is the mostly significant environmental risk factor for the occurrence and progress of basal cell carcinoma(BCC). Both cumulative and intermittent high-grade UVR exposure could promote the uncontrolled replication of skin cells. There are also exsiting other contributing environmental factors that combine with the UVR exposure to promote the development of BCC. DNA damage in formation of skin cancers is considered to be a result of UVR toxicity. It is UVR that could activate a series of oncogenes simultaneously inactivating tumor suppressor genes and aberrant proliferation and survival of keratinocytes that repair these damages. Furthermore, mounting evidence demonstrates that inflammatory responses of immune cells in the tumor microenvironment plays crucial role in the skin tumorigenesis as well. In this chapter, we will follow the function of UVR in the onset and development of BCC. We describe the factors that influence BCC induced by UVR, and also review the recent advances of pathogenesis of BCC induced by UVR from the genetic and inflammatory aspects.

Daily Lifestyle and Cutaneous Malignancies

Daily lifestyle is a fundamental part of human life and its influence accumulates daily in the human body. We observe that a good daily lifestyle has a beneficial impact on our health; however, the actual effects of individual daily lifestyle factors on human skin diseases, especially skin cancers, have not been summarized. In this review, we focused on the influence of daily lifestyle on the development of skin cancer and described the detailed molecular mechanisms of the development or regulation of cutaneous malignancies. Several daily lifestyle factors, such as circadian rhythm disruption, smoking, alcohol, fatty acids, dietary fiber, obesity, and ultraviolet light, are known to be associated with the risk of cutaneous malignancies, malignant melanoma, squamous cell carcinoma, basal cell carcinoma, and Merkel cell carcinoma. Although the influence of some daily lifestyles on the risk of skin cancers is controversial, this review provides us a better understanding of the relationship between daily lifestyle factors and skin cancers.

Body mass index and height and risk of cutaneous melanoma: Mendelian randomization analyses

BACKGROUND

Height and body mass index (BMI) have both been positively associated with melanoma risk, although findings for BMI have been less consistent than height. It remains unclear, however, whether these associations reflect causality or are due to residual confounding by environmental and lifestyle risk factors. We re-evaluated these associations using a two-sample Mendelian randomization (MR) approach.

METHODS

We identified single nucleotide polymorphisms (SNPs) for BMI and height from separate genome-wide association study (GWAS) meta-analyses. We obtained melanoma SNPs from the most recent melanoma GWAS meta-analysis comprising 12 874 cases and 23 203 controls. We used the inverse variance-weighted estimator to derive separate causal risk estimates across all SNP instruments for BMI and height.

RESULTS

Based on the combined estimate derived from 730 SNPs for BMI, we found no evidence of an association between genetically predicted BMI and melanoma [odds ratio (OR) per one standard deviation (1 SD) (4.6 kg/m2) increase in BMI 1.00, 95% confidence interval (CI): 0.91-1.11]. In contrast, we observed a positive association between genetically-predicted height (derived from a pooled estimate of 3290 SNPs) and melanoma risk [OR 1.08, 95% CI: 1.02-1.13, per 1 SD (9.27 cm) increase in height]. Sensitivity analyses using two alternative MR methods yielded similar results.

CONCLUSIONS

These findings provide no evidence for a causal association between higher BMI and melanoma, but support the notion that height is causally associated with melanoma risk. Mechanisms through which height influences melanoma risk remain unclear, and it remains possible that the effect could be mediated through diverse pathways including growth factors and even socioeconomic status.

The role of drugs and selected dietary factors in cutaneous squamous cell carcinogenesis

Cutaneous squamous cell carcinoma represents the second most common non-melanoma skin cancer and its incidence increases worldwide. This review provides an overview of selected exogenous risk factors for cutaneous squamous cell carcinoma, which include drugs (azathioprine, calcineurin inhibitors, hydrochlorothiazide, angiotensin-converting-enzyme inhibitors) and few dietary factors (fat meet, whole milk products, arsenic) to better understand squamous skin cancer etiopathogenesis. Ingredients such as leafy vegetables, nuts, fish, caffeine, niacin are preventive factors for cutaneous squamous cell cancer. The heart transplant recipients have an increased risk of squamous cell carcinoma development than kidney or liver transplant ones and switching photosensitizing azathioprine to mycophenolate mofetil can reduce the incidence of cutaneous squamous cell carcinoma. The great attention should be paid to early change of cardiac photosensitizing antihypertensive drugs to non-photosensitizing ones among patients with a history of prior skin cancers and among organ transplant recipients. Based on current knowledge that ultra-violet radiation is the main risk factor for squamous cell carcinoma development, promotion of the skin self-examination, photoprotection, tanning bed avoidance and early skin cancer diagnosis is important for this tumour prevention.

Lifestyle behaviors and sun exposure among individuals diagnosed with skin cancer: a cross-sectional analysis of 2018 BRFSS data

PURPOSE

With the continued increase in skin cancer incidence rates, the population of skin cancer survivors continues to grow. Understanding skin cancer survivors' lifestyle behaviors, including ultraviolet radiation exposure, is important in reducing skin cancer recurrences and improving health outcomes. The objective of this study is to compare the differences in lifestyle behaviors among skin cancer survivors or individuals who currently have skin cancer versus individuals who have never had a skin cancer diagnosis.

METHODS

To investigate these lifestyle behaviors, we performed a cross-sectional analysis comparing lifestyle behaviors in persons diagnosed with skin cancer and those without a history of skin cancer among US citizens using publicly available data from the 2018 Behavior Risk Factor Surveillance System (BRFSS).

RESULTS

In total, there were 437,436 respondents. No significant difference existed between the two cohorts in sunburn frequency, use of sun protection, or indoor tanning; in fact, males were more likely to be afflicted with sunburns following diagnosis. Skin cancer survivors were less likely to be current smokers and sedentary. Female survivors were more likely to binge and heavily drink alcohol.

CONCLUSION

Our findings highlight important areas for reducing risk factors, which could reduce the recurrence of skin malignancies in skin cancer survivors.

IMPLICATIONS FOR CANCER SURVIVORS

Our study provides insight to lifestyle behaviors among skin cancer survivors. Being aware of these behaviors has the potential to reduce skin cancer recurrence.

Do Diet and Lifestyles Play a Role in the Pathogenesis of NMSCs?

Background and Aims: Literature highlights the role of risk factors like age, body mass index (BMI), tobacco smoking, alcohol intake and diet in the pathogenesis of several cancer types but little is known for non-melanoma skin cancers (NMSC). The aim of this epidemiological study was to evaluate the correlation between modifiable risk factors (BMI, metabolic panel, diet, lifestyle, medical history) and not modifiable risk factors (gender, age) and NMSC development. Methods: From February 2018 to September 2019, 162 patients affected by NMSC were compared to a group of 167 controls. A univariate and multivariate analysis was conducted to elaborate the data collected through face-to-face interviews. Results: While our evidence did not always reach statistical significance, NMSC study group patients exhibited high rates of analyzed risk factors (male gender aging over 55 years, high BMI, reduced physical activity) compared to the control group. Conclusions: Our study indicates that practicing more than 30 min of physical activity daily could be a protective factor against the NMSC onset. Other risk factors were not correlated with NMSC, but more evidence is needed to establish a possible link.

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

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

Nonalcoholic Fatty Liver Disease: A Challenge from Mechanisms to Therapy

Focusing on previously published mechanisms of non-alcoholic fatty liver disease (NAFLD), their uncertainty does not always permit a clear elucidation of the grassroot alterations that are at the basis of the wide-spread illness, and thus curing it is still a challenge. There is somehow exceptional progress, but many controversies persist in NAFLD research and clinical investigation. It is likely that hidden mechanisms will be brought to light in the near future. Hereby, the authors present, with some criticism, classical mechanisms that stand at the basis of NAFLD, and consider contextually different emerging processes. Without ascertaining these complex interactions, investigators have a long way left ahead before finding an effective therapy for NAFLD beyond diet and exercise.

Association of Vitamin A Intake With Cutaneous Squamous Cell Carcinoma Risk in the United States

IMPORTANCE

Retinoids are bioactive forms of vitamin A that are essential in the maintenance of epithelial maturation and differentiation. Synthetic retinoids are used in chemoprevention of skin cancer among high-risk populations with potential adverse effects. Epidemiologic data on vitamin A intake and risk of cutaneous squamous cell carcinoma (SCC) are limited.

OBJECTIVE

To examine whether vitamin A intake is associated with a reduction in SCC risk.

DESIGN, SETTINGS, AND PARTICIPANTS

This cohort study prospectively examined intake of vitamin A and carotenoids and SCC risk in the Nurses' Health Study (1984-2012) and the Health Professionals Follow-up Study (1986-2012). Diet was assessed repeatedly. Incident SCC was confirmed by pathologic reports. Data analysis was performed from June 21, 2017, to December 4, 2018.

EXPOSURES

Intakes of vitamin A, retinol, and carotenoids.

MAIN OUTCOMES AND MEASURES

Incident SCC. Cox proportional hazards regression models were used to compute cohort-specific hazard ratios (HRs) and 95% CIs. Pooled HRs of the cohort-specific results were calculated.

RESULTS

A total of 3978 SCC cases in 75 170 women in the Nurses' Health Study (mean [SD] age, 50.4 [7.2] years) and 48 400 men in the Health Professionals Follow-up Study (mean [SD] age, 54.3 [9.9] years) were documented. Higher total vitamin A was associated with a reduction in SCC risk; with quintile 1 as the reference, the pooled multivariate HRs for the increasing quintiles of vitamin A intake were 0.97 (95% CI, 0.87-1.07) for quintile 2, 0.97 (95% CI, 0.80-1.17) for quintile 3, 0.93 (95% CI, 0.84-1.03) for quintile 4, and 0.83 (95% CI, 0.75-0.93) for quintile 5 (P < .001 for trend). Higher intakes of retinol and some carotenoids were also associated with a reduction in SCC risk; the pooled HRs for the highest quintiles of intake compared with the lowest quintiles were 0.88 (95% CI, 0.79-0.97; P = .001 for trend) for total retinol, 0.86 (95% CI, 0.76-0.96; P = .001 for trend) for beta cryptoxanthin, 0.87 (95% CI, 0.78-0.96; P < .001 for trend) for lycopene, and 0.89 (95% CI, 0.81-0.99; P = .02 for trend) for lutein and zeaxanthin. The results were generally consistent by sex and other SCC risk factors.

CONCLUSIONS AND RELEVANCE

This study suggests that increased intake of dietary vitamin A is associated with decreased risk of incident SCC. Future studies are needed to determine whether vitamin A supplementation has a role in chemoprevention of SCC.

Mediterranean dietary pattern and skin cancer risk: A prospective cohort study in French women

BACKGROUND

The Mediterranean diet (MD) has been reported to be associated with lower cancer risk. However, while previous studies explored major single components of the MD, only 1 previous study has investigated adherence to the MD in relation to melanoma risk.

OBJECTIVE

The aim of this study was to explore the relations between adherence to the MD and the risk of skin cancer, including melanomas, basal cell carcinomas (BCCs), and squamous cell carcinomas (SCCs).

DESIGN

Etude Epidémiologique auprès de femmes de la Mutuelle Générale de l'Education Nationale (E3N) is a prospective cohort of 98,995 French women aged 40-65 y in 1990. Dietary data were collected via a validated food questionnaire in 1993. Adherence to the MD was assessed using a 9-unit dietary score that incorporates intakes of fruit, vegetables, legumes, cereal products, olive oil, fish, dairy products, meat products, and alcohol. We used Cox proportional hazards regression models to compute HRs and 95% CIs adjusted for age and main known skin cancer risk factors.

RESULTS

From 1993 to 2008, a total of 2003 skin cancer cases were ascertained among 67,332 women, including 404 melanomas, 1367 BCCs, and 232 SCCs. Score of adherence to the MD was associated with lower risk of skin cancer (HR: 0.83; 95% CI: 0.73, 0.93 for high compared with low score, Ptrend = 0.001). MD score was also inversely and linearly associated with risks of melanoma (HR: 0.72; 95% CI: 0.54, 0.96; Ptrend = 0.02) and BCC (HR: 0.77; 95% CI: 0.66, 0.90; Ptrend = 0.0006) but not SCC (HR: 1.08; 95% CI: 0.75, 1.55; Ptrend = 0.68), although with no heterogeneity across skin cancer types (Pheterogeneity = 0.23).

CONCLUSION

These findings suggest that adherence to the MD is associated with a lower skin cancer risk in women, particularly melanoma and BCC. If confirmed in future research, these findings may have important implications in skin cancer prevention.

Obesity Update in Women

The Clinical Update series is intended to help busy providers stay up to date with important and potentially practice changing articles that have been published on topics pertinent to the care of women. The rates of obesity and the resultant morbidities are rising worldwide, making it a high-priority health issue for the medical community. Moreover, the pathophysiology and management of obesity and visceral fat accumulation in women has important nuances, distinct from those in men. It is important to consider the effect of unique female-specific influences such as reproductive stage and pregnancy. Therefore, we have chosen to review six high-impact recent studies relating to obesity and its management in women. These include guidelines for management of obesity in pregnancy, risk of nonmelanoma skin cancer in overweight/obese women, the association of vascular fat and decline in physical function in midlife women, the predictors for weight gain in premenopausal women with early-stage breast cancer, dietary patterns and obesity in postmenopausal women, and finally, normal weight obesity and mortality risk in postmenopausal women.

Overweight in midlife and risk of cancer in late life: A nationwide Swedish twin study

Our study examined whether midlife overweight (body mass index [BMI] ≥25) is associated with late-life cancer risk and explored the role of genetic and early-life environmental factors in this association. The study included 14,766 individuals from the Swedish Twin Registry, whose midlife (30-50 years) height and weight were recorded. Information on cancer diagnoses in late life (>65 years) was derived from the National Patient Registry and Cancer Registry. Generalized estimating equation (GEE) models were used to analyze unmatched case-control data (controlled for the clustering of twins within a pair). A co-twin matched case-control analysis used conditional logistic regression to compare cancer-discordant twins. Of all participants, 3968 (26.9%) were overweight and 4253 (28.8%) had cancer. In multi-adjusted GEE models using normal-weight (BMI 18.5-24.9) participants as the reference group, overweight was related to higher risk of colon cancer (OR 1.36, 95% CI: 1.00-1.84, p = 0.049), liver cancer (OR 2.00, 95% CI: 1.11-3.62), cervix uteri cancer (OR 2.86, 95% CI: 1.19-6.91) and corpus uteri cancer (OR 1.78, 95% CI: 1.14-2.78) but lower risk of nonmelanoma skin cancer (OR 0.77, 95% CI: 0.66-0.90). In conditional logistic regression analysis, these associations were attenuated becoming nonsignificance. The difference in ORs from the unmatched and matched analyses was not significant. In conclusion, midlife overweight is associated with increased risk of late-life colon, liver and uterine cancer but reduced risk of late-life nonmelanoma skin cancer. Further investigations are warranted to explore the role of genetic and early-life environmental factors in these associations.

Interaction of body mass index or waist-to-hip ratio and sun exposure associated with nonmelanoma skin cancer: A prospective study from the Women's Health Initiative

BACKGROUND

The incidence of nonmelanoma skin cancer (NMSC) exceeds the incidence of all other types of cancers combined. Cumulative sun exposure and intermittent sun exposure are known risk factors for the development of NMSC. Because obesity has been shown to decrease the risk of NMSC incidence, this study investigated whether the risk of NMSC with sun exposure was consistent across different levels of body size.

METHODS

Body size was assessed with the body mass index (BMI) and the waist-to-hip ratio (WHR). Sun exposure was assessed in watts and langleys and by the amount of time spent outdoors per day in the summer during a person's 30s.

RESULTS

Among 71,645 postmenopausal women eligible for inclusion in this study, 13,351 participants (18.6%) developed NMSC. A BMI ≥ 25 kg/m² or a WHR ≥ 0.80 was associated with lower NMSC hazard rates (hazard ratio for BMI, 0.78; hazard ratio for WHR, 0.89); however, the association between higher levels of sun exposure and a higher risk of NMSC was more apparent among women with a BMI ≥ 25 kg/m² or a WHR ≥ 0.80 in comparison with those of a normal weight (P for interaction for BMI < .001; P for interaction for WHR = .022).

CONCLUSIONS

Although most studies have considered sun exposure as a covariate, none have addressed the potential interaction of body size with sun exposure; therefore, the effect size of being overweight or obese may have been overestimated. In comparison to the normal-weight group, those in the overweight group had increasingly higher hazard rates with increasing sun exposure. Further studies are warranted to investigate how increased weight interacts with sun exposure to influence skin cancer pathogenesis.

Association between Height and Actinic Keratosis: A Nationwide Population-based Study in South Korea

The association between actinic keratosis (AK) and anthropometric measures has not been investigated. This study aims to evaluate the associations between anthropometric measures and the incidence of AK in South Korea. We analyzed clinical data from individuals aged over 20 years who received a health examination arranged by the national insurance program between 2005 and 2008. Newly diagnosed AK was identified using claims data from baseline to the date of diagnosis or until December 31, 2015. The incidence of AK was highest among the elderly (aged over 60 years) and showed a male bias. The risk of AK increased with greater height. The quintile with the greatest height had an increased risk of AK compared with the quintile with the lowest height (hazard ratio = 1.28, 95% confidence interval: 1.24-1.33) after adjustment for age, sex, income, smoking status, alcohol consumption, hypertension, dyslipidemia, myocardial infarction, congestive heart failure, and chronic obstructive pulmonary disease. This study showed a positive association between the incidence of AK and human height. However, it is unclear whether these findings can be generalized to Koreans who have not received an examination or to populations in other countries.

Ultraviolet radiation, vitamin D and the development of obesity, metabolic syndrome and type-2 diabetes

Obesity is increasing in prevalence in many countries around the world. Its causes have been traditionally ascribed to a model where energy intake exceeds energy consumption. Reduced energy output in the form of exercise is associated with less sun exposure as many of these activities occur outdoors. This review explores the potential for ultraviolet radiation (UVR), derived from sun exposure, to affect the development of obesity and two of its metabolic co-morbidities, type-2 diabetes and metabolic syndrome. We here discuss the potential benefits (or otherwise) of exposure to UVR based on evidence from pre-clinical, human epidemiological and clinical studies and explore and compare the potential role of UVR-induced mediators, including vitamin D and nitric oxide. Overall, emerging findings suggest a protective role for UVR and sun exposure in reducing the development of obesity and cardiometabolic dysfunction, but more epidemiological and clinical research is required that focuses on measuring the direct associations and effects of exposure to UVR in humans.

Fat Intake and Risk of Skin Cancer in U.S. Adults

Background: Fat intake has been associated with certain cancers, including colorectal, breast, and prostate cancers. However, literature on dietary fat and skin cancer has been limited.Methods: We examined the association between fat intake and risk of skin cancer including cutaneous malignant melanoma, squamous cell carcinoma (SCC), and basal cell carcinoma (BCC) within two prospective studies: the Nurses' Health Study (NHS) and the Health Professionals Follow-up Study (HPFS). Dietary information on total, saturated, monounsaturated, polyunsaturated, omega-6, and omega-3 fat and cholesterol was repeatedly assessed generally every 4 years. Incident cases were identified by self-report. Diagnosis on melanoma and SCC was confirmed by pathologic records.Results: A total of 794 melanoma, 2,223 SCC, and 17,556 BCC in the NHS (1984-2012) and 736 melanoma, 1,756 SCC, and 13,092 BCC in the HPFS (1986-2012) were documented. Higher polyunsaturated fat intake was associated with risk of SCC [pooled HR for highest vs. lowest quintiles, 1.16; 95% confidence interval (CI), 1.05-1.28; P_trend=0.001] and BCC (pooled HR, 1.06; 95% CI, 1.01-1.11; P_trend=0.01). Higher omega-6 fat intake was associated with risks of SCC, BCC, and melanoma. Omega-3 fat intake was associated with risk of BCC, but not with SCC or melanoma. No other fats were associated with melanoma risk. The associations were similar in women and men and by other skin cancer risk factors.Conclusions: Polyunsaturated fat intake was modestly associated with skin cancer risk.Impact: Further studies are needed to confirm our findings and to identify relevant biological mechanisms. Cancer Epidemiol Biomarkers Prev; 27(7); 776-82. ©2018 AACR.

An assessment of the relationship of physical activity, obesity, and chronic diseases/conditions between active/obese and sedentary/ normal weight American women in a national sample

OBJECTIVE

Obesity and physical inactivity are associated with increased rates of chronic diseases and conditions. However, the 'fit but fat' theory posits that cardiopulmonary fitness (or physical activity) can mitigate risks to health associated with obesity. The purpose of this study was to compare chronic diseases and conditions of highly active/obese women with inactive/normal weight women.

STUDY DESIGN

This was a cross-sectional study of the 2015 Behavioral Risk Factor Surveillance System data.

METHODS

Weighted descriptive statistics were performed to describe the demographic characteristics of the two groups. We calculated odds ratios and adjusted odds ratios for chronic diseases and conditions comparing highly active/obese women with inactive/normal weight women.

RESULTS

Highly active/obese women were more likely to report risk factors (hypertension, high cholesterol, and diabetes) for coronary heart disease (CHD) and cardiovascular disease (CVD) than inactive/normal weight women; however, they did not have increased rates of CVD, CHD, or heart attack and had decreased risk for stroke. Highly active/obese women had increased risk for asthma, arthritis, and depression, but not for cancer, kidney disease, or chronic obstructive pulmonary disease.

CONCLUSIONS

Highly active/obese women appear to be staving off the actual development of CHD and CVD; however, further research is needed to understand the long-term health benefits of physical activity among obese women.

Anthropometric factors and cutaneous melanoma: Prospective data from the population-based Janus Cohort

The aim of the present study was to prospectively examine risk of cutaneous melanoma (CM) according to measured anthropometric factors, adjusted for exposure to ultraviolet radiation (UVR), in a large population-based cohort in Norway. The Janus Cohort, including 292,851 Norwegians recruited 1972-2003, was linked to the Cancer Registry of Norway and followed for CM through 2014. Cox regression was used to estimate hazard ratios (HRs) of CM with 95% confidence intervals (CIs). Restricted cubic splines were incorporated into the Cox models to assess possible non-linear relationships. All analyses were adjusted for attained age, indicators of UVR exposure, education, and smoking status. During a mean follow-up of 27 years, 3,000 incident CM cases were identified. In men, CM risk was positively associated with body mass index, body surface area (BSA), height and weight (all ptrends  < 0.001), and the exposure-response curves indicated an exponential increase in risk for all anthropometric factors. Weight loss of more than 2 kg in men was associated with a 53% lower risk (HR 0.47, 95% CI: 0.39, 0.57). In women, CM risk increased with increasing BSA (ptrend  = 0.002) and height (ptrend  < 0.001). The shape of the height-CM risk curve indicated an exponential increase. Our study suggests that large body size, in general, is a CM risk factor in men, and is the first to report that weight loss may reduce the risk of CM among men.

A BET Bromodomain Inhibitor Suppresses Adiposity-Associated Malignant Transformation

Almost half a million of all new cancers have been attributed to obesity and epidemiologic evidence implicates visceral adipose tissue (VAT) and high-fat diets (HFD) in increasing cancer risk. We demonstrated that VAT-derived fibroblast growth factor 2 (FGF2) from mice fed an HFD or obese individuals stimulates the malignant transformation of epithelial cells. Mechanism-based strategies to prevent this VAT-enhanced tumorigenesis have not been explored. Clinical studies have indicated that bromodomain inhibitors have considerable potential as therapeutic agents for cancer by inhibiting the activity of several oncogenes, including c-Myc; however, their chemopreventive activity is unknown. We show herein that mice with visceral adiposity have elevated nuclear c-Myc expression in their epidermis. We hypothesized that the bromodomain inhibitor I-BET-762 (I-BET) would have efficacy in the prevention of malignant transformation by VAT and FGF2. We tested this hypothesis using our novel models of VAT-stimulated transformation in vitro and FGF2- stimulated tumor formation in vivo We found that I-BET significantly attenuates VAT and FGF2-stimulated transformation and inhibits VAT-induced c-Myc protein expression in several skin and breast epithelial cell lines. Moreover, I-BET attenuated tumor growth significantly in FGF2-treated nude mice. Work is ongoing to determine the role of visceral adiposity in c-Myc activity in several tissues and determine the inhibitory effect of I-BET on VAT-promoted tumors in vivoCancer Prev Res; 11(3); 129-42. ©2017 AACRSee related editorial by Berger and Scacheri, p. 125.

Fibroblast growth factor receptor is a mechanistic link between visceral adiposity and cancer

Epidemiological evidence implicates excess adipose tissue in increasing cancer risk. Despite a steeply rising global prevalence of obesity, how adiposity contributes to transformation (stage a non-tumorigenic cell undergoes to become malignant) is unknown. To determine the factors in adipose tissue that stimulate transformation, we used a novel ex vivo system of visceral adipose tissue (VAT)-condition medium-stimulated epithelial cell growth in soft agar. To extend this system in vivo, we used a murine lipectomy model of ultraviolet light B-induced, VAT-promoted skin tumor formation. We found that VAT from mice and obese human donors stimulated growth in soft agar of non-tumorigenic epithelial cells. The difference in VAT activity was associated with fibroblast growth factor-2 (FGF2) levels. Moreover, human and mouse VAT failed to stimulate growth in soft of agar in cells deficient in FGFR-1 (FGF2 receptor). We also demonstrated that circulating levels of FGF2 were associated with non-melanoma tumor formation in vivo. These data implicate FGF2 as a major factor VAT releases to transform epithelial cells-a novel, potential pathway of VAT-enhanced tumorigenesis. Strategies designed to deplete VAT stores of FGF2 or inhibit FGFR-1 in abdominally obese individuals may be important cancer prevention strategies as well as adjuvant therapies for improving outcomes.

Acne in late adolescence is not associated with a raised risk of subsequent malignant melanoma among men

BACKGROUND

To evaluate the association of acne in late adolescence with the risk for subsequent malignant melanoma (MM) in men.

METHODS

Swedish register-based cohort study of 242,096 males born between 1952 and 1956, who took part in compulsory assessments for Swedish military conscription in late adolescence between 1969 and 1975, with subsequent diagnoses of MM (n=1,058) up to December 31, 2009. Covariates included measures of childhood circumstances and information from adolescence on presence of acne, physical fitness, cognitive function, body mass index (BMI), and a summary of diagnoses. Cox regression was used for the analysis.

RESULTS

In total 1,058 men were diagnosed with MM. Acne was not associated with subsequent MM, with an adjusted hazard ratio (and 95% confidence interval) of 0.95 (0.61 to 1.49). Men with parents who were agricultural workers, and men who lived in northern Sweden, had lower physical fitness, or lower cognitive function had a lower risk of MM. Overweight and obesity was associated with a raised risk, with an adjusted hazard ratio of 1.39 (1.14, 1.71).

CONCLUSIONS

Acne in late adolescence is unlikely to represent a raised risk for subsequent MM in men. Overweight or obesity was identified as a raised risk for MM, possibly due to the associated increased skin surface area.

Role of BMI and hormone therapy in melanoma risk: a case-control study

BACKGROUND

Currently, the association between body mass index (BMI) and hormone therapies and Cutaneous Melanoma (CM) development is strongly debated. This study was carried out to assess the association between BMI, hormone therapies, and CM risk.

METHODS

The present study is a hospital-based case-control study with 605 consecutive CM patients and 592 controls treated for non-neoplastic conditions at the Department of Dermatology in Florence. The associations of melanoma risk with BMI and hormone therapies were assessed performing unconditional logistic regression to estimate odds ratios (OR) and their 95% confidence intervals, adjusting for potential confounders.

RESULTS

We found a significant interaction of BMI with age (P < 0.0001): being overweight significantly increased CM risk among individuals less than 50 years old (OR = 1.85 with 95% CI 1.14-2.94), whereas the association was not significant for individuals over 50 years old (OR = 1.15 with 95% CI 0.77-1.71). For oestrogen therapy, women taking oral contraceptives (OCs)/hormone replacement therapy (HRT) showed a lower CM risk than men (OR = 0.63, 95% CI 0.44-0.89), with risk estimates significantly lower (P < 0.0001) than in non OCs/HRT users, which had an increased risk compared to men (OR = 1.81, 95% CI 1.29-2.53).

CONCLUSIONS

Being overweight was significantly associated with CM risk, and this relationship was highly age-conditioned; the second finding was the protective effect of oestrogen therapies for women. Both findings may have a significant impact on melanoma prevention, as the prevalence of obesity and hormone therapy use is increasing worldwide.

Epidemiology of Keratinocyte Carcinoma

Purpose of the review

To provide a synopsis of recent research advances in the epidemiology of keratinocyte carcinoma (KC), with a focus on indoor tanning and known risk factors for other forms of cancer such as cigarette smoking and alcohol drinking.

Recent findings

The evidence is strong enough to infer that use of UVR-emitting indoor tanning devices cause KC. Epidemiologic studies of cigarette smoking, alcohol drinking, and menopausal hormone therapy all show some suggestion for increased risk of KC but the evidence is not yet strong enough to determine if there is a true etiologic role. Body mass index is clearly inversely associated with KC risk but this is more likely to be due to lower UVR exposure in overweight and obese individuals than it is due to a true etiologic role.

Summary

The epidemic of KC continues unabated, and the causal role of indoor tanning is contributing to this unfavorable trend in KC incidence rates. Advances in understanding the etiology of KC should not divert attention away from the fact that the primary public health strategy to prevent KC is known: minimize population exposure to UVR from the sun and from UVR-emitting indoor tanning devices, particularly among those with sun-sensitive phenotypes.

Niacin intake and risk of skin cancer in US women and men

A recent clinical trial found a protective role of niacinamide, a derivative of niacin, against skin cancer recurrence. However, there is no epidemiologic study to assess the association between niacin intake and risk of skin cancer [basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma]. We prospectively evaluated whether total, dietary and supplemental niacin intake was associated with skin cancer risk based on 72,308 women in the Nurses' Health Study (1984-2010) and 41,808 men in the Health Professionals Follow-up Study (1986-2010). Niacin intake was assessed every 2 to 4 years during follow-up and cumulative averaged intake. Cox proportional hazard models were used to compute the hazard ratios (HR) and 95% confidence intervals (CI) and cohort-specific results were pooled using a random-effects model. During the follow-up, we documented 23,256 BCC, 2,530 SCC and 887 melanoma cases. Total niacin intake was inversely associated with SCC risk; the pooled HR for top vs. bottom quintiles was 0.84 (95% CI = 0.74-0.95; ptrend  = 0.08). However, there were a marginally positive association between total niacin intake and BCC risk; the pooled HR for top versus bottom quintiles was 1.05 (95% CI = 1.01-1.10; ptrend  < 0.01). Higher total niacin intake was also marginally positively associated with melanoma risk in men, but not in women. The results were similar in stratified analyses according to sun exposure related factors and by body location of melanoma and SCC. Our study supports a potential beneficial role of niacin intake in relation to SCC but not of BCC or melanoma.

Sub-erythemal ultraviolet radiation reduces metabolic dysfunction in already overweight mice

Exposure to sunlight may limit cardiometabolic risk. In our previous studies, regular exposure to sub-erythemal (non-burning) ultraviolet radiation (UVR) reduced signs of adiposity and cardiometabolic dysfunction in mice fed a high-fat diet. Some of the observed effects were dependent on skin release of nitric oxide after UVR exposure. Here, we examine the effects of sub-erythemal UVR on signs of adiposity and metabolic dysfunction in already overweight mice, comparing the effects of two sunlamps with distinct emitted light spectra. Mice were fed a high-fat diet from 8 weeks of age, with UVR administered twice a week from 14 weeks of age until they were killed at 20 weeks of age. Mice were irradiated with the same dose of UVB radiation (1 kJ/m²) from either FS40 (65% UVB, 35% UVA) or CLEO (4% UVB, 96% UVA) sunlamps, but substantially more UVA from the latter. FS40 UVR (but not CLEO UVR) significantly reduced mouse weights and weight gain, compared to mice fed a high-fat diet (only). These effects were dependent on nitric oxide. Conversely, CLEO UVR (but not FS40 UVR) significantly reduced circulating LDL cholesterol. Both light sources reduced fasting insulin levels, and the extent of hepatic steatosis; the latter was reversed by topical application of cPTIO, suggesting an important role for skin release of nitric oxide in preventing hepatic lipid accumulation. These results suggest that there may be a number of benefits achieved by regular exposure to safe (non-burning) levels of sunlight or UV-containing phototherapy, with effects potentially dependent on the predominance of the wavelengths of UVR administered.

Cutaneous squamous cell carcinoma: an epidemiological review

Cutaneous squamous cell carcinoma (SCC) is a common cancer in white populations and its disease burden is often substantially underestimated. SCC occurs more often in men than women and increases dramatically with age; those affected often develop multiple primaries over time, which increases the burden. The main external cause is solar ultraviolet radiation (UVR), with immunosuppression being the other established risk factor, shown by the high SCC rates in organ transplant recipients. Sunbed use and certain genetic disorders and medical conditions are also associated with SCC, while associations with human papillomavirus infection and high bodyweight are not established. The presence of actinic keratoses (AKs) on sun-damaged skin is one of the strongest predictors of SCC in unaffected people and a very small proportion of AKs are SCC precursors, although the true rate of malignant transformation of AKs is unknown. The mainstay of SCC prevention is protection of the skin from undue sun exposure by use of clothing cover and sunscreen during summer or in sunny places. Educational, behavioural and multicomponent interventions directed at individuals ranging from parents of newborns, to school children and adolescents, to outdoor workers, have repeatedly been shown to be effective in improving sun-protective behaviours. Health policies can facilitate SCC prevention by setting standards for relevant behaviours to reduce UVR exposure, for example, by legislated restriction of the tanning industry. Skin cancer prevention initiatives are generally highly cost-effective and public investment should be encouraged to control the growing public health problems caused by SCC.

Body mass index, height and early-onset basal cell carcinoma in a case-control study

INTRODUCTION

Basal cell carcinoma (BCC) is the most common malignancy in the US. Body mass index (BMI) and height have been associated with a variety of cancer types, yet the evidence regarding BCC is limited. Therefore, we evaluated BMI and height in relation to early-onset BCC (under age 40) and explored the potential role of ultraviolet (UV) radiation exposure and estrogen-related exposures in the BMI-BCC relationship.

METHODS

BCC cases (n=377) were identified through a central dermatopathology facility in Connecticut. Control subjects (n=389) with benign skin conditions were randomly sampled from the same database and frequency matched to cases on age (median=36, interquartile range 33-39), gender, and biopsy site. Participants reported weight (usual adult and at age 18), adult height, sociodemographic, phenotypic, and medical characteristics, and prior UV exposures. We calculated multivariate odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models.

RESULTS

Adult BMI was inversely associated with early-onset BCC (obese vs. normal OR=0.43, 95% CI=0.26-0.71). A similar inverse association was present for BMI at age 18 (OR=0.54, 95% CI=0.34-0.85). Excluding UV exposures from the BMI models and including estrogen-related exposures among women only did not alter the association between BMI and BCC, indicating limited mediation or confounding. We did not observe an association between adult height and BCC (OR per cm=1.00, 95% CI=0.98-1.02).

CONCLUSIONS

We found a significant inverse association between BMI and early-onset BCC, but no association between height and BCC. This association was not explained by UV exposures or estrogen-related exposures in women.

Arbeitsbedingte Synkanzerogenese an der Haut - Zur kombinatorischen Einwirkung zweier Karzinogene der Berufskrankheiten-Liste

HINTERGRUND

Die Synkanzerogenese am Hautorgan, wissenschaftlich unstrittig, spiegelt sich im monokausal geleiteten Berufskrankheiten (BK)-Recht nicht wider. Nichtmelanozytäre Hauttumoren und deren Vorläuferläsionen können nur nach Einzelprüfung der BK-Nrn. 5103 und 5102 anerkannt werden.

METHODIK

Retrospektive Auswertung von 28 zwischen September 2012 und September 2015 begutachteten Fällen (Altersmedian 72,5 J.) mit nichtmelanozytären Hauttumoren und deren Vorläuferläsionen und arbeitsbedingter Exposition gegenüber natürlicher UV-Strahlung und polyzyklischen aromatischen Kohlenwasserstoffen.

ERGEBNISSE

In allen 28 Fällen sahen wir die arbeitstechnischen Voraussetzungen nach den BK-Nrn. 5103 und 5102 als erfüllt an. In 26 Fällen (93 %) empfahlen wir die Hautkrebserkrankung als BK-Tatbestand nach den Nrn. 5103 und 5102 anzuerkennen. Dem folgte der Unfallversicherungsträger in vier Fällen. Achtmal wurde die Anerkennung nur nach BK-Nr. 5103, zehnmal nur nach BK-Nr. 5102 und viermal gar nicht ausgesprochen.

SCHLUSSFOLGERUNGEN

Bei nichtmelanozytären Hauttumoren oder deren Vorläuferläsionen an UV-exponierten Hautarealen mit ausreichend kumulativer arbeitsbedingter natürlicher UV-Strahlenexposition und bei arbeitsbedingter Exposition gegenüber polyzyklischen aromatischen Kohlenwasserstoffen sollten mittels BK-Anzeige die "BK-Nrn. 5103 und 5102 im Sinne der Synkanzerogenese" gemeldet werden. Neben der gerechteren Wiedergabe der Arbeitsplatzrealitäten in einem solchen Feststellungsverfahren kann es dann im Konkreten auch zur Anerkennung von Basalzellkarzinomen kommen, die ansonsten, bei alleiniger Prüfung der BK-Nr. 5103, herausgerechnet würden.

Body mass index and risk of non-melanoma skin cancer: cumulative evidence from prospective studies

Prospective epidemiologic studies that investigated the association between body mass index (BMI) and non-melanoma skin cancer (NMSC) yielded inconsistent findings. A dose-response meta-analysis was conducted to quantitatively summarize the evidence. PubMed and Embase databases were searched for relevant studies. Study-specific relative risk (RR) and 95% confidence interval (CI) for an increase in BMI of 5 kg/m² was computed with the generalized least squares trend estimation, and these risk estimates were combined with the random-effects model. Nine publications were included in the final analyses, consisting of 18 independent cohorts with 22 risk estimates (971,795 participants and 50,561 NMSC cases). Results of the dose-response analyses showed a nonlinear inverse relationship between BMI and NMSC (RR = 0.88, 95% CI: 0.85–0.91, I² = 71.2%, P-nonlinearity <0.001), which persisted when limiting to the studies with adjustment for important potential confounders including sun exposure and sensitivity factors. The risk estimates were very similar for squamous cell carcinoma and basal cell carcinoma. Sex appeared a source of heterogeneity (P-difference = 0.06), with a weaker, but still significant inverse association in men than in women. This dose-response meta-analysis suggests a nonlinear inverse association between BMI and NMSC.

Obesity as a risk factor for malignant melanoma and non-melanoma skin cancer

The dramatic increases in incidence of both obesity and many cancers including skin cancer emphasize the need to better understand the pathophysiology of both conditions and their connections. Melanoma is considered the fastest growing cancer and rates of non-melanoma skin cancer have also increased over the last decade. The molecular mechanisms underlying the association between obesity and skin cancer are not clearly understood but emerging evidence points to changes in the tumor microenvironment including aberrant cell signaling and genomic instability in the chronic inflammatory state many obese individuals experience. This article reviews the literature linking obesity to melanoma and non-melanoma skin cancer.

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.

Immunohistochemical Expression of Leptin in Non Melanoma Skin Cancer

INTRODUCTION

Obesity in adults is associated with numerous health disorders including some forms of cancer. Various epidemiological studies have found a link between excess adiposity and malignant melanoma; however, the association with non melanoma skin cancer is questionable. Leptin is a hormone produced mainly by the adipose tissue and its serum level may reflect body mass index. Leptin is reported to promote proliferation and angiogenesis and deregulate apoptosis, therefore facilitates the process of carcinogenesis.

AIM

The current study tried to assess leptin localization and expression in non melanoma skin cancer to verify its possible role in pathogenesis of this cancer.

MATERIALS AND METHODS

This study was carried out on 13 Basal Cell Carcinoma (BCC) cases and 14 Squamous Cell Carcinoma (SCC) cases together with 19 normal skin biopsies as a control group using immunohistochemical method.

RESULTS

Leptin was expressed in 52.6% of the normal epidermis with pure cytoplasmic and both cytoplasmic and nuclear staining patterns. All cases of SCC (100%) and two cases of BCC (15.4%) showed leptin expression in tumour cells whereas nuclear expression was in favour of SCC. Stromal expression of leptin was seen in both SCC (57.1%) and BCC (38.5%) without significant differences. Percentage of leptin expression by tumour cells in SCC showed positive linear correlation with tumour size (p=0.02) and microvessel density (p=0.000). Stromal expression of leptin in SCC was associated with large tumour size (p=0.04), advanced stage (p=0.01) and tumours arising in sites other than head and neck (p=0.01).

CONCLUSION

Leptin could have a more important role in pathogenesis of cutaneous SCC rather than BCC that may reflect the trivial role of obesity in induction of BCC. The expression of leptin by tumour and stromal cells of SCC could co-operate in its progression by promoting angiogenesis with subsequently acquiring large tumour size and then advanced stage.