Diet, plasma levels of beta-carotene and alpha-tocopherol, and risk of malignant melanoma

Nutrition and melanoma: the contribution of trace elements in onset, progression, and treatment of melanoma

Melanoma is a highly malignant and drug-resistant disease that imposes a substantial economic burden on the world. There are many studies linking trace elements to diverse types of cancers, including melanoma. This review elucidates the relationship between trace elements exposure and melanoma. It was identified that copper, manganese, selenium, zinc, iron, and many other trace elements were associated with melanoma in humans. In terms of epidemiology, different elements have different correlations with melanoma. These trace elements affect the occurrence and development of melanoma through various mechanisms, such as oxidative stress and the MAPK pathway. The literature on the role of trace elements in the pathogenesis and treatment of melanoma depicts promising prospects for this field.

Alcohol as a Non-UV Social-Environmental Risk Factor for Melanoma

Although cancer mortality has declined among the general population, the incidence of melanoma continues to rise. While identifying high-risk cohorts with genetic risk factors improves public health initiatives and clinical care management, recognizing modifiable risk factors such as social-environmental risk factors would also affect the methods of patient outreach and education. One major modifiable social-environmental risk factor associated with melanoma is ultraviolet (UV) radiation. However, not all forms of melanoma are correlated with sun exposure or occur in sun-exposed areas. Additionally, UV exposure is rarely associated with tumor progression. Another social-environmental factor, pregnancy, does not explain the sharply increased incidence of melanoma. Recent studies have demonstrated that alcohol consumption is positively linked with an increased risk of cancers, including melanoma. This perspective review paper summarizes epidemiological data correlating melanoma incidence with alcohol consumption, describes the biochemical mechanisms of ethanol metabolism, and discusses how ethanol and ethanol metabolites contribute to human cancer, including melanoma.

Nutritional Interventions for Patients with Melanoma: From Prevention to Therapy-An Update

Melanoma is an aggressive skin cancer, whose incidence rates have increased over the past few decades. Risk factors for melanoma are both intrinsic (genetic and familiar predisposition) and extrinsic (environment, including sun exposure, and lifestyle). The recent advent of targeted and immune-based therapies has revolutionized the treatment of melanoma, and research is focusing on strategies to optimize them. Obesity is an established risk factor for several cancer types, but its possible role in the etiology of melanoma is controversial. Body mass index, body surface area, and height have been related to the risk for cutaneous melanoma, although an 'obesity paradox' has been described too. Increasing evidence suggests the role of nutritional factors in the prevention and management of melanoma. Several studies have demonstrated the impact of dietary attitudes, specific foods, and nutrients both on the risk for melanoma and on the progression of the disease, via the effects on the oncological treatments. The aim of this narrative review was to summarize the main literature results regarding the preventive and therapeutic role of nutritional schemes, specific foods, and nutrients on melanoma incidence and progression.

Effect of antioxidants coenzyme Q10 and β-carotene on the cytotoxicity of vemurafenib against human malignant melanoma

Melanoma is a type of highly invasive skin cancer derived from melanocytes with poor prognosis. Vemurafenib (PLX4032) is a clinically approved targeted therapeutic for BRAF mutant melanoma that has a high therapeutic response rate and significantly prolongs the overall survival time of patients with melanoma. Antioxidants have been widely used as supplements for cancer prevention and for decreasing the side effects of cancer therapy. However, antioxidants can also protect cancer cells from oxidative stress and promote cancer growth and progression. The present study aimed to examine the effect of the antioxidants coenzyme Q10 (CoQ10) and β-carotene on melanoma cell growth and invasiveness and on the cytotoxicity of vemurafenib against both vemurafenib-sensitive (SK-MEL-28) and vemurafenib-resistant (A2058) human malignant melanoma cell lines. MTS assay and wound-healing assay demonstrated that CoQ10 alone significantly reduced the viability and migration of melanoma cells, respectively, and synergistically worked with vemurafenib to decrease the viability and migration of human melanoma cells. In contrast, MTS assay and flow cytometry revealed that β-carotene alone did not affect the viability and apoptosis induction of melanoma cells; however, it inhibited cell migration and invasiveness. Wound-healing and Transwell assay demonstrated that β-carotene alleviated the cytotoxicity of vemurafenib and mitigated the inhibitory effect of vemurafenib on cell migration and invasion. Both CoQ10 and β-carotene protected melanoma cells from undergoing apoptosis induced by vemurafenib. Immunoblotting demonstrated that β-carotene at physiological concentration worked synergistically with vemurafenib to suppress the Ras-Raf-Mek-Erk intracellular signaling pathway. The present study aimed to add to the evidence of the in vitro effects of CoQ10 and β-carotene on the antimelanoma effects of vemurafenib.

Holistic dermatology: An evidence-based review of modifiable lifestyle factor associations with dermatologic disorders

BACKGROUND

Holistic dermatology focuses on treating the human body as a whole and implementing lifestyle changes to enhance the treatment and prognosis of skin disease. Understanding the interplay between modifiable lifestyle factors and patients' dermatologic health will help physicians better inform patients on self-care methods to mitigate the burden of their skin disease(s).

OBJECTIVE

To review the current scientific literature on the relationship between modifiable lifestyle factors and the dermatologic outcome of skin disorders.

METHODS

A systematic literature search on PubMed, Cochrane, and Web of Science was conducted to identify research articles examining the relationship between dermatology and 6 major categories of modifiable lifestyle factors: diet, sleep, exercise, stress, alcohol, and smoking.

RESULTS

A substantial amount of evidence supports the relationship between modifiable lifestyle factors and dermatologic outcomes. There were the most studies on diet, stress, alcohol, and smoking, but all lifestyle factors were supported by some degree of scientific evidence.

CONCLUSION

All modifiable lifestyle factors explored in this review play a critical role in modulating the onset and progression of skin disease. We anticipate more research studies in the future and an increasing integration of holistic dermatology into patient care.

The Benefits and Risks of Certain Dietary Carotenoids that Exhibit both Anti- and Pro-Oxidative Mechanisms-A Comprehensive Review

Carotenoid pigments, particularly β-carotene and lycopene, are consumed in human foodstuffs and play a vital role in maintaining health. β-carotene is known to quench singlet oxygen and can have strong antioxidant activity. As such, it was proposed that β-carotene might reduce the risk of cancer. Epidemiological studies found inverse relationships between cancer risk and β-carotene intake or blood levels. However, clinical trials failed to support those findings and β-carotene supplementation actually increased lung cancer incidence in male smokers. Early experimental animal studies found dietary β-carotene inhibited UV-induced skin cancers. Later studies found that β-carotene supplementation exacerbated UV-carcinogenic expression. The discrepancies of these results were related to the type of diet the animals consumed. Lycopene has been associated with reduced risk of lethal stage prostate cancer. Other carotenoids, e.g., lutein and zeaxanthin, play a vital role in visual health. Numerous studies of molecular mechanisms to explain the carotenoids' mode of action have centered on singlet oxygen, as well as radical reactions. In cellular systems, singlet oxygen quenching by carotenoids has been reported but is more complex than in organic solvents. In dietary β-carotene supplement studies, damaging pro-oxidant reactivity can also arise. Reasons for this switch are likely due to the properties of the carotenoid radicals themselves. Understanding singlet oxygen reactions and the anti-/pro-oxidant roles of carotenoids are of importance to photosynthesis, vision and cancer.

Dietary Fat Intake and the Risk of Skin Cancer: A Systematic Review and Meta-Analysis of Observational Studies

We conducted a meta-analysis to evaluate the association between fat intake and the risk of three major types of skin cancer including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and cutaneous malignant melanoma (CMM). A comprehensive search of PubMed and EMBASE was performed to identify all relevant observational studies published up to December 1, 2018. Specific odds ratio (OR) or relative risk (RR) estimates for the highest versus the lowest intake of dietary fat and 95% confidence intervals (CI) from the included studies were pooled using random effect model. Three prospective cohort studies (175,675 participants and 30,915 BCC cases, 4,106 SCC cases and 1,638 CMM cases) and nine case-control studies (328 BCC cases, 493 SCC cases, 1,547 CMM cases and 2,660 controls) were identified. The pooled results indicated that dietary consumption of total fat and saturated fat were not associated with three major types of skin cancer. High consumption of monounsaturated fat was significantly associated with a decreased risk of BCC (RR: 0.90, 95% CI: 0.85-0.96) and high level of polyunsaturated fat intake was potentially positively associated with SCC (RR: 1.19, 95% CI: 1.06-1.33). Our findings should be confirmed by further evidence from well-designed and large-scale prospective cohort studies.

Exposure to Trace Elements and Risk of Skin Cancer: A Systematic Review of Epidemiologic Studies

Exposure to environmental trace elements has been studied in relation to many cancers. However, an association between exposure to trace elements and skin cancer remains less understood. Therefore, we conducted a systematic review of published epidemiologic literature examining the association between exposure to trace elements, and risk of melanoma and keratinocyte carcinoma in humans. We identified epidemiologic studies investigating exposure to arsenic, cadmium, chromium, copper, iron, selenium, and zinc and risk of skin cancer in humans. Among the minerals, arsenic, selenium, and zinc had more than five studies available. Exposure to arsenic was associated with increased risk of keratinocyte carcinoma, while too few studies existed on melanoma to draw conclusions. Exposure to selenium was associated with possible increased risk of keratinocyte carcinoma. Studies of zinc and skin cancer were case-control in design and were found to have inconsistent associations. The data on the association between cadmium, chromium, copper, and iron and risk of skin cancer remain too sparse to draw any conclusions. In summary, epidemiologic studies on exposure to trace elements and cutaneous malignancies are limited. Studies with larger sample sizes and prospective designs are warranted to improve our knowledge of trace elements and skin cancer.

Alcohol Intake and Risk of Incident Melanoma: A Pooled Analysis of Three Prospective Studies in the United States

BACKGROUND

Alcohol consumption is associated with increased risk of numerous cancers, but existing evidence for an association with melanoma is equivocal. No study has evaluated the association with different anatomic locations of melanoma.

METHODS

We used data from three large prospective cohort studies to investigate whether alcohol intake was associated with risk of melanoma. Alcohol intake was assessed repeatedly by food-frequency questionnaires. A Cox proportional hazards model was used to calculate multivariate-adjusted hazard ratios (HRs).

RESULTS

A total of 1,374 cases of invasive melanoma were documented during 3,855,706 person-years of follow-up. There was an association between higher alcohol intake and incidence of invasive melanoma (pooled multivariate HR 1.14 [95% confidence interval (CI), 1.00-1.29] per drink/day; P_trend = 0.04). Among alcoholic beverages, white wine consumption was associated with an increased risk of melanoma (pooled multivariate HR 1.13 [95% CI, 1.04-1.24] per drink/day; P_trend <0.01) after adjusting for other alcoholic beverages. The association between alcohol consumption and melanoma risk was stronger for melanoma in relatively UV-spared sites (trunk) versus more UV-exposed sites (head, neck, or extremities). Compared with nondrinkers, the pooled multivariate-adjusted HRs for ≥20 g/day of alcohol were 1.02 (95% CI, 0.64-1.62; P_trend = 0.25) for melanomas of the head, neck, and extremities and 1.73 (95% CI, 1.25-2.38; P_trend = 0.02) for melanomas of the trunk.

CONCLUSIONS

Alcohol intake was associated with a modest increase in the risk of melanoma, particularly in UV-protected sites.

IMPACT

These findings further support American Cancer Society Guidelines for Cancer Prevention to limit alcohol intake. Cancer Epidemiol Biomarkers Prev; 25(12); 1550-8. ©2016 AACR.

Alcohol, alcoholic beverages, and melanoma risk: a systematic literature review and dose-response meta-analysis

PURPOSE

Several studies in recent years have investigated the relationship between alcohol intake and melanoma risk, with conflicting results. To help clarify this issue, we conducted a literature review and dose-response meta-analysis of studies published until June 30th, 2017, that examined the association between alcohol intake (overall and by beverage type) and melanoma risk.

METHODS

We used random effect models with maximum likelihood estimation to calculate summary relative risk (SRR) and 95% confidence intervals (95%CI).

RESULTS

We included 20 independent studies (encompassing 10,555 melanoma cases and over 1.6 million non-cases/controls) published during 1986-2016, of which six had a prospective cohort study design. Adjustment for phenotypic characteristics and sunlight exposure was performed in 11 and nine studies, respectively. Alcohol intake was moderately associated with melanoma risk: the SRR were 1.29 (95% CI 1.14-1.45) for those in the highest vs. lowest category of current alcohol intake, and 1.96 (95% CI 1.02-3.76, I² = 0%) for cumulative intake. In the dose-response analysis, the increase in risk associated with a 10 g increment in daily alcohol intake was 1.07 (95% CI 1.03-1.11). Risk estimates did not differ by gender, study design and adjustment for confounders; between-studies heterogeneity was acceptable, and there was no evidence of publication bias.

CONCLUSIONS

Our findings suggest that alcohol drinking may be moderately associated with increased melanoma risk, although residual confounding and bias cannot be ruled out. Further research is needed to confirm these findings, clarify the role of the different alcohol sources, and investigate the interaction with known melanoma risk factors.

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.

Systematic review of studies investigating the association between dietary habits and cutaneous malignant melanoma

OBJECTIVE

Several papers have dealt with diet as a risk factor for cutaneous malignant melanoma (CMM). This study aimed to synthesize available data on the topic.

STUDY DESIGN

A systematic review of observational studies assessing the association between dietary habits and CMM was performed.

METHODS

Electronic databases were used to identify eligible articles. Quality was assessed through the Newcastle-Ottawa scale. Case-control and cohort studies evaluating the intake of food/nutrients through the assessment of dietary habits and the occurrence of CMM were considered eligible. Data comparing the highest and lowest levels of consumption were collected from single studies and described qualitatively as data combination was not possible. Results were reported as percentages on the basis of relative risks and odds ratios.

RESULTS

Eighteen studies reported in 21 articles were selected. Cohort studies showed better quality than case-control studies. Most articles did not detect any significant association between food/nutrient intake and CMM, except for limited evidence of a protective role associated with fish, vegetables and fruit. Risk reduction was shown to be 35-37%, 40-57% and 34-46%, respectively, in studies reporting significant results. Similarly, few articles showed protective roles of beta-carotene and vitamins A, C, D and E, with risk reduction of 64%, 37-43%, 41%, 15-39% and 50-66%, respectively.

CONCLUSION

A trend towards reduced risk of CMM associated with higher intake of fish, vegetables and fruit, as well as beta-carotene and vitamins A, C, D and E, has been shown but further research is needed to provide decisive data.

Alcohol intake and early-onset basal cell carcinoma in a case-control study

BACKGROUND

Previous epidemiological studies of overall alcohol intake and basal cell carcinoma (BCC) are inconsistent, with some evidence for differences by type of alcoholic beverage. While alcohol may enhance the carcinogenicity of ultraviolet (UV) radiation, this has not been evaluated in existing epidemiological studies.

OBJECTIVES

To evaluate alcohol intake in relation to early-onset BCC, and explore potential interactions with UV exposure.

METHODS

Basal cell carcinoma cases (n = 380) and controls with benign skin conditions (n = 390) under 40 years of age were identified through Yale Dermatopathology. Participants provided information on lifetime alcohol intake, including type of beverage, during an in-person interview. Self-reported data on indoor tanning and outdoor sunbathing were used to categorize UV exposure. We calculated odds ratios (OR) and 95% confidence intervals (CIs) using unconditional multivariate logistic regression in the full sample and in women only.

RESULTS

There was no statistically significant association between lifetime alcohol intake and early-onset BCC overall [above median intake vs. no regular alcohol intake (OR 1·10, 95% CI 0·69-1·73)] or in women only (OR 1·21, 95% CI 0·73-2·01). Similarly, intake of red wine, white wine, beer or spirits and mixed drinks was not associated with early-onset BCC. In exploratory analyses, we saw limited evidence for an interaction (P(interaction) = 0·003), with highest risk for high alcohol and high UV exposures, especially in women, but subgroup risk estimates had wide and overlapping CIs.

CONCLUSIONS

Overall, we did not observe any clear association between lifetime alcohol intake and early-onset BCC.

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 A intake and risk of melanoma: a meta-analysis

BACKGROUND

Mounting evidence from experimental and animal studies suggests that vitamin A may have a protective effect on melanoma, but the findings on the association of vitamin A intake with risk of melanoma have been inconsistently reported in epidemiologic studies. We attempted to elucidate the association by performing a meta-analysis.

METHODS

Eligible studies were identified by searching PubMed and EMBASE databases, as well as by reviewing the references of retrieved publications. Summary odds ratios (OR) with corresponding 95% confidence interval (CI) were computed with a random-effects model. Study-specific ORs and 95% CIs for the highest vs. lowest categories of vitamin A intake were pooled.

RESULTS

A total of 8 case-control studies and 2 prospective studies comprising 3,328 melanoma cases and 233,295 non-case subjects were included. The summary OR for the highest compared with the lowest intake of total vitamin A, retinol and beta-carotene was 0.86 (95% CI = 0.59-1.25), 0.80 (95% CI = 0.69-0.92) and 0.87 (95%CI = 0.62-1.20), respectively. Significant heterogeneity was observed among studies on vitamin A and beta-carotene intake, but not among studies on retinol intake. Subgroup and sensitivity analyses confirmed these findings. There was no indication of publication bias.

CONCLUSION

Findings from this meta-analysis suggest that intake of retinol, rather than of total vitamin A or beta-carotene, is significantly associated with reduced risk of melanoma.

Use of food frequency questionnaire to assess relationships between dietary habits and cardiovascular risk factors in NESCAV study: validation with biomarkers

BACKGROUND

Validation of Food frequency questionnaire (FFQ) is particularly important element, as incorrect information may lead to false associations between dietary factors and diseases. The aim of the study was to evaluate the validity of the FFQ used in NESCAV (Nutrition, Environment and Cardiovascular Health) study, by comparing the estimated intakes of fruits and vegetables and of several micro-nutrients with corresponding nutritional biomarkers.

METHODS

Relative validity was assessed in a sample of 922 subjects (452 men and 470 women). Comparisons between FFQ-estimates and their corresponding biomarkers were performed through correlation and cross classification into quintiles by using both crude and energy-adjusted FFQ-estimates. Correlations adjusted for confounders were also computed. All analyses were performed separately for men and women.

RESULTS

Concerning micro-nutrients, significant correlations were found for vitamin B9, D, E, B12 β-carotene and iodine in both men and women. Energy-adjustment led to an increase of all correlations cited previously. However, after excluding supplement users, correlations for vitamin D were not significant anymore. Concerning fruits and vegetables, all correlations were significant. Vegetables alone and fruits and vegetables correlated better in men (r around 0.2) than in women (r around 0.1). In men, correlation was also better for vegetables alone and fruits and vegetables than fruits alone.

CONCLUSION

These data demonstrate that this FFQ is a reasonable tool to assess intakes of fruits and vegetables and of several micro-nutrients. We conclude that our FFQ is suitable to be used in NESCAV study, although protein and vitamin D estimates should be interpreted with caution.

Low-fat diet and skin cancer risk: the women's health initiative randomized controlled dietary modification trial

BACKGROUND

Large cohort studies have reported no relationship between dietary fat and nonmelanoma skin cancer (NMSC), although a low-fat diet intervention reduced NMSC risk in a small clinical trial. In animal studies, skin tumor development has been reduced by low-fat diet. We evaluated the effect of a low-fat dietary pattern on NMSC and melanoma in the Women's Health Initiative Dietary Modification trial.

METHODS

Postmenopausal women aged 50 to 79 years (n = 48,835) were randomly assigned to the low-fat dietary pattern intervention (n = 19,541) or comparison group (n = 29,294). The intervention goals included decreasing fat intake to 20% or less of calories, increasing vegetable and fruit intake, and increasing grain intake. Self-reported incident NMSC (n = 4,907) and physician-adjudicated incident melanoma (n = 279) were ascertained every 6 months.

RESULTS

Over 8.1 years of follow-up, the low-fat diet intervention did not affect overall incidence of NMSC [HR 0.98; 95% confidence interval (CI), 0.92-1.04] or melanoma (HR, 1.04; 95% CI, 0.82-1.32). In subgroup analyses of melanoma risk, baseline fat intake interacted significantly with group assignment (Pinteraction = 0.006). Among women with higher baseline fat intake, the dietary intervention significantly increased risk (HR, 1.48; 95% CI, 1.06-2.07), whereas, among women with lower baseline fat intake, the intervention tended to reduce melanoma risk (HR, 0.72; 95% CI, 0.50-1.02).

CONCLUSIONS

In this large randomized trial, a low-fat dietary pattern did not affect overall incidence of NMSC or melanoma.

IMPACT

A low-fat diet does not reduce incidence of NMSC, but an interaction between baseline fat intake and dietary intervention on melanoma risk warrants further investigation.

Serum Fatty acids and risk of cutaneous melanoma: a population-based case-control study

Background. Some observational studies have suggested that excess dietary intake of polyunsaturated fatty acids such as linoleic acid increases cutaneous melanoma risk. We aimed at examining the association between serum fatty acids and melanoma risk by conducting a population-based case-control study in a northern Italy community. Methods. The percentage composition of 12 fatty acids was determined in 51 newly diagnosed melanoma patients and 51 age- and sex-matched population controls by extracting total lipids from serum samples using thin layer and gas chromatography. Conditional logistic regression was used to estimate the relative risk of melanoma associated with tertiles of percentage composition of each fatty acid as well as groupings including saturated, monounsaturated, and polyunsaturated fatty acids. Results. We found a slightly increased melanoma risk for stearic and arachidic acids proportion, with and without adjustment for potential confounders. For an n-3 polyunsaturated fatty acid, docosapentaenoic acid, we found a male-specific direct association with melanoma risk. No other associations emerged for the other saturated, monounsaturated, and polyunsaturated fatty acids, individually or grouped by type. Conclusions. These findings do not suggest a major role of fatty acids, including linoleic acid, on risk of cutaneous melanoma, though their evaluation is limited by the small sample size.

Association of vitamin A and carotenoid intake with melanoma risk in a large prospective cohort

Laboratory data suggest that intake of vitamin A and carotenoids may have chemopreventive benefits against melanoma, but epidemiological studies examining the association have yielded conflicting results. We examined whether dietary and supplemental vitamin A and carotenoid intake was associated with melanoma risk among 69,635 men and women who were participants of the VITamins And Lifestyle (VITAL) cohort study in western Washington. After an average of 5.84 years of follow-up, 566 incident melanomas were identified. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of melanoma associated with dietary, supplemental, and total vitamin A and carotenoid intake after adjusting for melanoma risk factors. Baseline use of individual retinol supplements was associated with a significant reduction in melanoma risk (HR: 0.60; 95% CI: 0.41-0.89). High-dose (>1,200 μg per day) supplemental retinol was also associated with reduced melanoma risk (HR: 0.74; 95% CI: 0.55-1.00), as compared with non-users. The reduction in melanoma risk was stronger in sun-exposed anatomic sites. There was no association of melanoma risk with dietary or total intake of vitamin A or carotenoids. Retinol supplementation may have a preventative role in melanoma among women.

Inverse association between dietary vitamin D and risk of cutaneous melanoma in a northern Italy population

The possibility of an inverse association between vitamin D and risk of cancer and, in particular, of cutaneous malignant melanoma has been suggested, but results of epidemiologic studies are still conflicting. We examined the relation between dietary vitamin D intake and melanoma risk through a population-based case-control study (380 cases, 719 controls) in a northern region of Italy, a country with an average vitamin D intake lower than that in northern Europe or the United States. We assessed average daily intake of vitamin D from foodstuffs using the European Prospective Investigation into Cancer and Nutrition (EPIC) semiquantitative food frequency questionnaire. In this population, levels of vitamin D intake were considerably lower than those observed in recent U.S. studies. We found an inverse relation between dietary vitamin D and melanoma risk in the sample as a whole, in both crude and adjusted analyses. In sex- and age-specific analyses, this association appeared to be stronger among males and among older subjects. These findings suggest that, at the relatively low levels of intake observed in this sample, an inverse relation between dietary vitamin D and risk of cutaneous malignant melanoma may exist.

Nutrition and melanoma prevention

Melanoma has continued to rise in incidence despite public efforts to promote sun protection behaviors. Because sunscreen use does not completely prevent skin cancer induced by ultraviolet radiation, additional chemopreventive methods for protecting against and reversing the effects of ultraviolet photodamage need evaluation. Recent years have brought increased interest in dietary factors, such as natural botanicals and vitamins, for the prevention of melanoma. This contribution provides a narrative review of the relevant, nutrition-related literature found by searching the keywords "melanoma chemoprevention," "nutrition and melanoma," "dietary botanicals and melanoma prevention," "green tea and melanoma," "vitamin D and melanoma," and "vitamin E and melanoma" in the PubMed database. Although randomized controlled trials of humans are lacking, basic science and epidemiologic studies show promising benefits of many natural products in chemoprevention for melanoma. Future studies, hopefully, will yield concrete answers and clarify the role of commonly available dietary nutrients in melanoma chemoprevention.

Outpatient Follow-up and Secondary Prevention for Melanoma Patients

Health care providers and their patients jointly participate in melanoma prevention, surveillance, diagnosis, and treatment. This paper reviews screening and follow-up strategies for patients who have been diagnosed with melanoma, based on current available evidence, and focuses on methods to assess disease recurrence and second primary occurrence. Secondary prevention, including the roles of behavioral modification and chemoprevention are also reviewed. The role of follow-up dermatologist consultation, with focused physical examinations complemented by dermatoscopy, reflectance confocal microscopy, and/or full-body mapping is discussed. Furthermore, we address the inclusion of routine imaging and laboratory assessment as components of follow-up and monitoring of advanced stage melanoma. The role of physicians in addressing the psychosocial stresses associated with a diagnosis of melanoma is reviewed.

Antioxidant supplementation and risk of incident melanomas: results of a large prospective cohort study

OBJECTIVE

To examine whether antioxidant supplement use is associated with melanoma risk in light of recently published data from the Supplementation in Vitamins and Mineral Antioxidants (SUVIMAX) study, which reported a 4-fold higher melanoma risk in women randomized to receive a supplement with nutritionally appropriate doses of antioxidants.

DESIGN

Population-based prospective study (Vitamins and Lifestyle [VITAL] cohort).

SETTING

Western Washington State.

PARTICIPANTS

A total of 69 671 men and women who self-reported (1) intake of multivitamins and supplemental antioxidants, including selenium and beta carotene, during the past 10 years and (2) melanoma risk factors on a baseline questionnaire. Main Outcome Measure Incident melanoma identified through linkage to the Surveillance, Epidemiology, and End Results (SEER) cancer registry.

RESULTS

Cox proportional hazards regression models were used to estimate multivariable relative risks (RRs) and 95% confidence intervals (CIs) for multivitamin, supplemental selenium, and supplemental beta carotene use. After adjusting for melanoma risk factors, we did not detect a significant association between multivitamin use and melanoma risk in women (RR, 1.14; 95% CI, 0.78-1.66) or in men (RR, 1.09; 95% CI, 0.83-1.43). Moreover, we did not observe increased melanoma risk with the use of supplemental beta carotene (RR, 0.87; 95% CI, 0.48-1.56) or selenium (RR, 0.98; 95% CI, 0.69-1.41) at doses comparable with those of the SUVIMAX study. Conclusion Antioxidants taken in nutritional doses do not seem to increase melanoma risk.

Safety evaluation of topical applications of ethanol on the skin and inside the oral cavity

Ethanol is widely used in all kinds of products with direct exposure to the human skin (e.g. medicinal products like hand disinfectants in occupational settings, cosmetics like hairsprays or mouthwashes, pharmaceutical preparations, and many household products). Contradictory evidence about the safety of such topical applications of the alcohol can be found in the scientific literature, yet an up-to-date risk assessment of ethanol application on the skin and inside the oral cavity is currently lacking.The first and foremost concerns of topical ethanol applications for public health are its carcinogenic effects, as there is unambiguous evidence for the carcinogenicity of ethanol orally consumed in the form of alcoholic beverages. So far there is a lack of evidence to associate topical ethanol use with an increased risk of skin cancer. Limited and conflicting epidemiological evidence is available on the link between the use of ethanol in the oral cavity in the form of mouthwashes or mouthrinses and oral cancer. Some studies pointed to an increased risk of oral cancer due to locally produced acetaldehyde, operating via a similar mechanism to that found after alcoholic beverage ingestion.In addition, topically applied ethanol acts as a skin penetration enhancer and may facilitate the transdermal absorption of xenobiotics (e.g. carcinogenic contaminants in cosmetic formulations). Ethanol use is associated with skin irritation or contact dermatitis, especially in humans with an aldehyde dehydrogenase (ALDH) deficiency.After regular application of ethanol on the skin (e.g. in the form of hand disinfectants) relatively low but measurable blood concentrations of ethanol and its metabolite acetaldehyde may occur, which are, however, below acute toxic levels. Only in children, especially through lacerated skin, can percutaneous toxicity occur.As there might be industry bias in many studies about the safety of topical ethanol applications, as well as a general lack of scientific research on the long-term effects, there is a requirement for independent studies on this topic. The research focus should be set on the chronic toxic effects of ethanol and acetaldehyde at the point of impact, with special regard to children and individuals with genetic deficiencies in ethanol metabolism.

Vitamin D and skin cancer: a meta-analysis

A comprehensive bibliographic search of the literature was conducted to identify studies on Cutaneous Malignant Melanoma (CMM) and non-melanoma skin cancer (NMSC), Vitamin D receptor (VDR) polymorphisms, Vitamin D intake and 25(OH)D serum levels. Fully adjusted risk estimates were found and extracted for the two polymorphisms FokI and BsmI and Vitamin D intake. Ten studies were included in the meta-analysis, with a total of 6805 skin cancer cases. We found an association with CMM for both polymorphisms. The summary relative risks (SRR) for the studies on CMM were: 1.21 (1.03-1.42) and 1.21 (0.95-1.54) for the Ff and ff versus wild-type of FokI, respectively. The SRR for ff versus wild-type became significant with the inclusion of NMSC. The SRR for the studies on CMM were: 0.78 (0.65-0.92) and 0.75 (0.59-0.95) for the Bb and BB versus wild-type of BsmI, respectively. There is also a slight indication of a role of dietary Vitamin D in CMM development. In conclusion, this meta-analysis suggests a possible significant role of VDR FokI and BsmI polymorphism in CMM and NMSC risk. The association with Vitamin D intake is less clear and further studies could be useful to clarify the role of diet.

Superior survival of females among 10,538 Dutch melanoma patients is independent of Breslow thickness, histologic type and tumor site

BACKGROUND

Worldwide, female melanoma patients have superior survival compared with males, which is usually ascribed to earlier detection among women and/or a more favorable site distribution. We studied gender difference in melanoma survival in a large population-based setting after adjusting for tumor-related variables and offer clues for further research.

PATIENTS AND METHODS

A total of 10,538 patients diagnosed with melanoma from 1993 to 2004 in The Netherlands were included. Multivariate analyses were carried out to estimate adjusted relative excess risk (RER) of dying for men compared with women, adjusted for the patient and tumor characteristics.

RESULTS

Univariate relative survival analyses showed a RER of dying of 2.70 [95% confidence interval (CI) 2.38-3.06] for men compared with women. After adjusting for time period of diagnosis, region, age, Breslow thickness, histologic subtype, body site, nodal and metastatic status, a significant excess mortality risk was still present for males (RER 1.87, 95% CI 1.65-2.10). Among patients with advanced disease and in those < 45 or > or = 60, the adjusted risk estimates were similar.

CONCLUSIONS

The superior survival of women compared with men persisted after adjusting for multiple confounding variables indicating that factors other than stage at diagnosis and body site reduce mortality risk in female melanoma patients.

Circulating adiponectin levels in relation to melanoma: A case–control study

AIM

Melanoma, a malignancy with steadily increasing prevalence, has been associated not only with sun exposure but also with phenotypic characteristics including obesity. Adiponectin, an adipocyte secreted endogenous insulin sensitizer, has been found to play a protective role in several obesity related cancers but has not yet been studied in relation to melanoma. We investigated the association of circulating adiponectin levels with melanoma in Greece, a country with rather low incidence of the disease and high annual sunshine levels.

METHODS

In the context of a case-control study, we studied over a 22-month period 55 patients with incident, histologically confirmed melanoma cases and 165 healthy controls matched for gender and age.

RESULTS

After controlling for the possible confounding effect of education, body mass index and waist-to-hip ratio in multiple logistic regression analyses, sun sensitive skin type was significantly and positively associated with melanoma risk (OR: 2.48, 95% Confidence Interval: 1.22-5.10, p: 0.01). On the contrary, there was a sizeable, though non-significant, inverse association of serum adiponectin levels with the disease (OR: 0.75, 95% Confidence Interval: 0.52-1.10, p: 0.14).

CONCLUSION

A protective role of adiponectin in the development of melanoma cannot be excluded given the presented empirical evidence (25% reduction per one SD of adiponectin) and the direct anti-neoplastic features of the hormone. The results are intriguing enough to point to the need for further investigation.

Malignant melanoma in the 21st century, part 1: epidemiology, risk factors, screening, prevention, and diagnosis

Malignant melanoma is an aggressive, therapy-resistant malignancy of melanocytes. The incidence of melanoma has been steadily increasing worldwide, resulting in an increasing public health problem. Exposure to solar UV radiation, fair skin, dysplastic nevi syndrome, and a family history of melanoma are major risk factors for melanoma development. The interactions between genetic and environmental risk factors that promote melanomagenesis are currently the subject of ongoing research. Avoidance of UV radiation and surveillance of high-risk patients have the potential to reduce the population burden of melanoma. Biopsies of the primary tumor and sampling of draining lymph nodes are required for optimal diagnosis and staging. Several clinically relevant pathologic subtypes have been identified and need to be recognized. Therapy for early disease is predominantly surgical, with a minor benefit noted with the use of adjuvant therapy. Management of systemic melanoma is a challenge because of a paucity of active treatment modalities. In the first part of this 2-part review, we discuss epidemiology, risk factors, screening, prevention, and diagnosis of malignant melanoma. Part 2 (which will appear in the April 2007 issue) will review melanoma staging, prognosis, and treatment.

Manganese superoxide dismutase polymorphism and risk of skin cancer (United States)

OBJECTIVE

We assessed whether the functional V16A polymorphism in the MnSOD gene is associated with skin cancer risk.

METHODS

We conducted a nested case-control study (219 melanoma, 286 squamous cell carcinoma (SCC), and 300 basal cell carcinoma (BCC) cases, and 873 matched controls) within the Nurses' Health Study. Genotyping was performed by the 5' nuclease assay (TaqMan). We used logistic regression to model the association between the genotype and skin cancer risk.

RESULTS AND CONCLUSIONS

Overall, there was no significant association between this polymorphism and the risk of each type of skin cancer. No significant interaction was observed between this polymorphism and sunburn history and constitutional susceptibility on skin cancer risk. For interactions between intakes of alpha-carotene and beta-carotene and the MnSOD polymorphism on SCC, the inverse association of intake of either carotene with SCC risk was limited to the Val carriers, whereas no association was observed among women with the AA genotype. We observed an interaction between total vitamin C intake and the MnSOD polymorphism on melanoma risk. No interaction was observed for the intakes of other carotenoids, vitamin E, and vitamin A. Further research is needed to confirm these possible associations.

Dietary intake of fruit and vegetable and lung cancer risk: a case–control study in Harbin, northeast China

BACKGROUND

We studied the relationship between dietary intake of vegetables and fruit and lung cancer risk in Harbin, Heilongjiang province, northeast China, an area with a very high baseline risk of lung cancer in both sexes.

PATIENTS AND METHODS

We used data from a case-control study, conducted from 1987 to 1990, among 218 cases with incident, histologically confirmed lung cancer and 436 controls admitted to the same hospitals as cases with non-neoplastic, non-lung diseases unrelated to smoking and other potential risk factors for lung cancer.

RESULTS

Compared with the lowest tertile of intake of vegetables, fruit or both, the multivariate odds ratios (ORs) for the highest tertile of intake were 0.39 [95% confidence interval (CI) 0.25-0.62], 0.73 (95% CI 0.48-1.11) and 0.40 (95% CI 0.25-0.63), respectively. In particular, high intake of Chinese cabbage (OR = 0.53), chives (OR = 0 .54), carrots (OR = 0.51) and celery (OR = 0.40) was inversely associated with lung cancer. The OR was more than six-fold elevated for smokers reporting low intake of vegetables, and more than four-fold elevated for smokers reporting low intake of fruit, as compared with never smokers reporting high intake of these items.

CONCLUSION

In agreement with previous studies, we found an inverse relation between vegetable and fruit intake and lung cancer risk in both strata of current and never smokers.

A population-based case–control study of diet and melanoma risk in northern Italy

Objective

We aimed at examining the association between dietary constituents and risk of cutaneous melanoma.

Design

In an area of northern Italy we recruited 59 newly diagnosed melanoma patients and 59 age- and sex-matched population controls, to whom we administered a validated semi-quantitative food-frequency questionnaire.

Results

We found an excess risk of melanoma in subjects with a higher energy-adjusted intake of total polyunsaturated fatty acids and, in particular, of linoleic acid (relative risk = 2.16 for intake in the highest tertile compared with the lowest tertile,Pfor linear trend = 0.061). Conversely, disease risk was inversely associated with the consumption of soluble carbohydrates (relative risk = 0.34 for intake in the upper vs. the lowest tertile adjusting for total energy intake,Pfor linear trend = 0.046). No other dietary factors, including alcohol, vitamins and trace elements, correlated with melanoma risk. The association of melanoma risk with linoleic acid and soluble carbohydrates intakes was further strengthened in multivariate analysis, and when analysis was limited to females.

Conclusions

Overall, these results indicate that an excess energy-adjusted intake of linoleic acid and a lower consumption of soluble carbohydrates may increase melanoma risk.

Melanoma chemoprevention

BACKGROUND

Despite efforts to promote sun protection behaviors, melanoma incidence continues to increase. The prognosis of advanced melanoma remains extremely poor in spite of treatment advances, emphasizing the importance of exploring additional preventive measures.

OBJECTIVE

We sought to summarize the results of published research on candidate chemoprevention agents for melanoma.

METHODS

We conducted a narrative review of the literature.

RESULTS

Investigation into a possible role in melanoma chemoprevention continues for multiple agents, including sunscreen, lipid-lowering medications, nonsteroidal anti-inflammatory drugs, dietary nutrients, immunomodulators, and other drugs, including retinoids, difluoromethylornithine, and T4 endonuclease V.

LIMITATIONS

Systematic review of the literature was not performed.

CONCLUSION

Because no agent yet emerges as a clear choice for effective melanoma chemoprevention, sun avoidance and sun protection remain the mainstay of melanoma prevention for persons at high risk.

Sun exposure, diet, and melanoma in Hawaii Caucasians

Much uncertainty remains about the type of sunlight exposure that most increases risk of cutaneous melanoma and the role of diet. The authors conducted a population-based case-control study (1986-1992) of Caucasians living on Oahu, Hawaii; included were 278 cases and age- and sex-matched controls. Plasma samples were measured for retinol, carotenoids, and alpha-tocopherol by high-pressure liquid chromatography. Selenium was measured in blood and toenails by neutron activation. Celtic and English ancestries, migration to Hawaii before age 20 years, fair complexion, inability to tan, and family history of skin cancer, as well as height, hours spent in the summer sun, blistering sunburns during adolescence, and moles, all increased melanoma risk. With regard to diet and biomarkers, only alcohol was associated with risk. The odds ratios for increasing tertiles of lifetime ethanol intake were 1.0, 1.2 (95% confidence interval (CI): 0.6, 2.2), and 2.3 (95% CI: 1.2, 4.4) (p for trend = 0.01) for men and 1.0, 1.1 (95% CI: 0.5, 2.4), and 1.7 (95% CI: 0.7, 3.8) (p for trend = 0.19) for women. Dietary lipids were unrelated to risk, but polyunsaturated fat intake appeared to modify the effects of alcohol and toenail selenium on melanoma risk. These data provide additional evidence for the association of constitutional susceptibility factors, intense sun exposure (particularly before age 20 years), and alcohol consumption with melanoma risk.

Association between dietary fat and skin cancer in an Australian population using case-control and cohort study designs

BACKGROUND

Human studies of dietary fat as a possible risk factor for cutaneous malignant melanoma (CMM) and non-melanoma skin cancer (NMSC)--principally basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)--have produced inconsistent results. We had the opportunity to examine the association concurrently for all three types of skin cancer in a population-based study in Tasmania, Australia, involving 652 cases of CMM, BCC and SCC and a common set of 471 controls.

METHODS

Histopathologically-confirmed cases of CMM, BCC and SCC were ascertained from the Tasmanian Cancer Registry (TCR), and controls were selected at random from the state's electoral roll. We compared subjects categorised by thirds of dietary fat intake score measured by the 'Dobson short fat questionnaire', with logistic regression models that adjusted for age, sex, skin type and usual sun exposure. We then followed all subjects for 56-80 months until 31 August, 2004 for a new NMSC using record linkage with both the TCR and the Births, Deaths, and Marriages registry. Incidence rates were calculated and ratios of rates were estimated using Poisson models.

RESULTS

Relative to subjects in the lowest fat intake category, the odds ratios (OR) comparing cases and controls were OR = 0.76 (95% CI: 0.56-1.03) for medium fat intake, and OR = 0.62 (95% CI: 0.45-0.85) for high fat intake, with a significant (p < 0.01) trend of reduced odds ratio with higher category dietary fat intake. Among cases, the incidence rate ratio (IRR) relative to those with lowest fat score was IRR = 0.72 (95% CI: 0.50-1.03) for medium fat intake, and IRR = 0.82 (95% CI: 0.56-1.20) for highest fat intake (linear trend p = 0.30).

CONCLUSION

Using the same dietary instrument with two study designs in the same Caucasian population, we found no evidence that high fat intake increases the risk of developing melanoma or non-melanoma skin cancers. Instead, our results suggest a risk reduction for high fat intake.

Environmental exposure to trace elements and risk of cutaneous melanoma

PURPOSE

Our aim was to examine the risk of melanoma in association with exposure to trace elements of toxicological and nutritional interest.

METHODS

We analyzed the concentrations of cadmium, lead, chromium, selenium, copper and zinc in toenails of 58 patients with newly diagnosed cutaneous melanoma as well as in 58 age- and sex-matched control subjects, randomly selected from the population of Modena province in northern Italy.

RESULTS

Melanoma risk was substantially unrelated to toenail levels of cadmium, chromium, lead and selenium. Subjects with higher toenail copper levels showed an excess risk, both in the crude analysis and after adjusting for sun exposure and level of education, while in both analyses high iron concentrations were associated with a decreased risk of the disease. A weak direct association between zinc levels and melanoma risk also emerged in the multivariate analysis.

CONCLUSIONS

Overall, these results do not suggest an involvement of heavy metals in melanoma etiology, while they do give some support to a possible role of zinc and, in particular, copper and iron exposure in influencing disease risk. However, these findings must be evaluated with caution due to the limited statistical stability of the point estimates.

Trace elements and melanoma

Melanoma incidence has been steadily increasing in recent years in most western countries, thus suggesting a role of environmental risk factors. Among these determinants, it has been hypothesized that some trace elements of nutritional and toxicological interest may be implicated in the etiology of the disease. We examined patients with newly diagnosed melanoma of the skin and population controls from the Modena province northern Italy. Clinical and dietary data were collected through questionnaires, and toenails were sampled for trace element determination. Levels of cadmium, chromium, lead, selenium, zinc, copper and iron in toenails were measured by inductively coupled plasma optical emission spectrometry and by neutron activation analysis. Data obtained from 58 cases and 58 controls indicated higher levels of copper and lower concentrations of iron in melanoma patients, whilst no other differences were seen for the remaining elements. Patterns of correlations of zinc and copper with the estimated intake of some dietary factors were different between cases and controls. Results of the present study suggest that abnormal intake or metabolism of copper and of iron might be implicated in the etiology of melanoma, whilst they do not indicate an involvement of exposure to cadmium, chromium, lead, selenium and zinc in this disease.

Risk of melanoma and vitamin A, coffee and alcohol: a case–control study from Italy

Limited information is available on the association between the risk of cutaneous malignant melanoma (CMM) and dietary factors. The issue was investigated using data from a case-control study conducted in Italy between 1992 and 1994, including 542 patients with incident, histologically confirmed CMM and 538 controls, admitted to the same hospitals as cases for non-dermatologic and non-neoplastic diseases. We found a significant inverse association between vitamin A intake and CMM risk. The multivariate odds ratio, after allowance for phenotypic characteristics and history of sunburns, for the highest, compared with the lowest, quartile of intake was 0.71 (95% confidence interval (CI) 0.50-1.02) for beta-carotene, 0.57 (95% CI 0.39-0.83) for retinol, and 0.51 (95% CI 0.35-0.74) for total vitamin A. We found no appreciable association of CMM risk with selected food items, including fish, meat, vegetables, fruit, dairy products, wholemeal bread, alcohol, coffee and tea drinking. Consumption of tea appeared to have a protective effect on CMM risk. The relations with measures of dietary vitamin A are, however, moderate compared with the associations between phenotypic characteristics, sun exposure and number of naevi and CMM risk.

Validation of a food-frequency questionnaire assessment of carotenoid and vitamin E intake using weighed food records and plasma biomarkers: The method of triads model

BACKGROUND

Reliability or validity studies are important for the evaluation of measurement error in dietary assessment methods. An approach to validation known as the method of triads uses triangulation techniques to calculate the validity coefficient of a food-frequency questionnaire (FFQ).

OBJECTIVE

To assess the validity of an FFQ estimates of carotenoid and vitamin E intake against serum biomarker measurements and weighed food records (WFRs), by applying the method of triads.

DESIGN

The study population was a sub-sample of adult participants in a randomised controlled trial of beta-carotene and sunscreen in the prevention of skin cancer. Dietary intake was assessed by a self-administered FFQ and a WFR. Nonfasting blood samples were collected and plasma analysed for five carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, lycopene) and vitamin E. Correlation coefficients were calculated between each of the dietary methods and the validity coefficient was calculated using the method of triads. The 95% confidence intervals for the validity coefficients were estimated using bootstrap sampling.

RESULTS

The validity coefficients of the FFQ were highest for alpha-carotene (0.85) and lycopene (0.62), followed by beta-carotene (0.55) and total carotenoids (0.55), while the lowest validity coefficient was for lutein (0.19). The method of triads could not be used for beta-cryptoxanthin and vitamin E, as one of the three underlying correlations was negative.

CONCLUSIONS

Results were similar to other studies of validity using biomarkers and the method of triads. For many dietary factors, the upper limit of the validity coefficients was less than 0.5 and therefore only strong relationships between dietary exposure and disease will be detected.