Risk factors for cutaneous melanoma: a case-control study in Argentina

Pathogenic mechanisms and etiologic aspects of Mycobacterium avium subspecies paratuberculosis as an infectious cause of cutaneous melanoma

Infectious etiologies have previously been proposed as causes of both melanoma and non-melanoma skin cancer. This exploratory overview explains and presents the evidence for the hypothesis that a microorganism excreted in infected ruminant animal feces, Mycobacterium avium subspecies paratuberculosis (MAP), is the cause of some cases of cutaneous melanoma (CM). Occupational, residential, and recreational contact with MAP-contaminated feces, soil, sand, and natural bodies of water may confer a higher rate of CM. Included in our hypothesis are possible reasons for the differing rates and locations of CM in persons with white versus nonwhite skin, why CM develops underneath nails and in vulvar skin, why canine melanoma is an excellent model for human melanoma, and why the Bacille Calmette-Guérin (BCG) vaccine has demonstrated efficacy in the prevention and treatment of CM. The pathogenic mechanisms and etiologic aspects of MAP, as a transmittable agent underlying CM risk, are carefully deliberated in this paper. Imbalances in gut and skin bacteria, genetic risk factors, and vaccine prevention/therapy are also discussed, while acknowledging that the evidence for a causal association between MAP exposure and CM remains circumstantial.

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

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

Skin Cancer Risk, Sun-Protection Knowledge and Behavior in Athletes-A Narrative Review

Outdoor sports are associated with increased exposure to ultraviolet radiation, which may result in sunburn, solar damage, and skin cancers. Water and winter sports create additional adverse conditions, such as washing away sunscreen by water and reflection of UV rays by the water and snow. Sweating-increased skin photosensitivity and activity-induced immunosuppression are associated with a greater risk of developing skin cancers. In this review, we focus on a group of athletes and sports participants and analyze 62 articles concerning sun exposure during outdoor sports, the risk of developing skin cancer, and knowledge and behavior regarding photoprotection methods. Various practices have been linked to an increased risk of developing basal cell carcinoma (BCC), squamous cell carcinoma (SCC), malignant melanoma (MM), or UV-induced skin damage. Water sports and mountaineering increase the risk of BCC. Surfing and swimming are risk factors for SCC. Melanoma is more common in swimmers, surfers, and marathon runners. Photoprotection behaviors can reduce potential skin damage and skin cancers. Athletes' knowledge about the risk of malignant lesions was satisfactory, but despite the risks, outdoor sports participants seem not to protect themselves from the sun adequately.

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

Simple Summary

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

Abstract

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

Ambient UVR and Environmental Arsenic Exposure in Relation to Cutaneous Melanoma in Iowa

Intermittent sun exposure is the major environmental risk factor for cutaneous melanoma (CM). Cumulative sun exposure and other environmental agents, such as environmental arsenic exposure, have not shown consistent associations. Ambient ultraviolet radiation (UVR) was used to measure individual total sun exposure as this is thought to be less prone to misclassification and recall bias. Data were analyzed from 1096 CM cases and 1033 controls in the Iowa Study of Skin Cancer and Its Causes, a population-based, case-control study. Self-reported residential histories were linked to satellite-derived ambient UVR, spatially derived environmental soil arsenic concentration, and drinking water arsenic concentrations. In men and women, ambient UVR during childhood and adolescence was not associated with CM but was positively associated during adulthood. Lifetime ambient UVR was positively associated with CM in men (OR for highest vs. lowest quartile: 6.09, 95% confidence interval (CI) 2.21–16.8), but this association was not as strong among women (OR for highest vs. lowest quartile: 2.15, 95% CI 0.84–5.54). No association was detected for environmental soil or drinking water arsenic concentrations and CM. Our findings suggest that lifetime and adulthood sun exposures may be important risk factors for CM.

Photoprotection in Outdoor Sports: A Review of the Literature and Recommendations to Reduce Risk Among Athletes

Solar exposure, for long hours and often at peak times with limited shade available, predisposes athletes to episodic sunburn and chronic damage, causing increased risk of precancerous lesions and skin cancer. Environmental factors and training intensity affect risk. Clothing provides good protection, but changing established “uniforms” may not be possible for reasons of practicality, safety, or simply custom. Although physical activity should be encouraged for its physical and mental benefits, risk of skin damage should be minimised. We review existing behaviours, skin cancer risk, and campaigns in the sporting population and highlight key recommendations to help sun protection practices become engrained in sports practice.

Aetiology and Pathogenesis of Cutaneous Melanoma: Current Concepts and Advances

Melanoma develops from malignant transformations of the pigment-producing melanocytes. If located in the basal layer of the skin epidermis, melanoma is referred to as cutaneous, which is more frequent. However, as melanocytes are be found in the eyes, ears, gastrointestinal tract, genitalia, urinary system, and meninges, cases of mucosal melanoma or other types (e.g., ocular) may occur. The incidence and morbidity of cutaneous melanoma (cM) are constantly increasing worldwide. Australia and New Zealand are world leaders in this regard with a morbidity rate of 54/100,000 and a mortality rate of 5.6/100,000 for 2015. The aim of this review is to consolidate and present the data related to the aetiology and pathogenesis of cutaneous melanoma, thus rendering them easier to understand. In this article we will discuss these problems and the possible impacts on treatment for this disease.

Cutaneous melanoma in Argentina: an analysis of its characteristics and regional differences

Purpose

This study aims to increase the knowledge about the characteristics of cutaneous melanoma in Argentina, their association with the risk of having Breslow ≥1 mm and mortality trends for the period 2002-2017.

Patients and methods

Descriptive statistics and regression analyses were done for 10.199 cases within the Argentine Melanoma Registry in the period 2002-2018. Trends in age-standardised mortality rates (ASMR) were analysed using the Join point Regression Model.

Results

Cases showed lesions mainly located in males' trunk (37%) and in females' lower limbs (29%). The level of invasion was higher in males who also showed higher mortality. Cases from the North West and North East regions showed a major risk of Breslow >1 mm and harboured CM in lower limbs more frequently than in other regions. Nearly, 25% of tumours over 2 mm were in cases aged <50 years and 37.6% in patients ≥50 years. In the North West, North East and Patagonia, the frequency of cases in young people was higher than in older people. In 43% of cases, the melanoma subtype was not specified in the report. The number of superficial spreading melanomas, the most common histology, was nearly twice that of Nodular melanomas the following histology in importance (3,403 and 1,754, respectively). Melanoma mortality rates in all Argentine population increased in the elderly. Lower melanoma mortality rates were observed in the North West. In 2007-2017, ASMR decreased significantly in females (average 1.4% p/year) while it increased nonsignificantly in males (0.4% p/year).The tumours with the worst prognosis were associated with the elderly, males, nodular or acrolentiginous morphologies, residing somewhere other than Centro and Patagonia and with tumors located in the head/neck and legs.

Conclusion

The geographical variations found for melanoma characteristics and their mortality in Argentina, makes it imperative that epidemiological research is continued to avoid generalisations and improve future preventive actions.

Potassium Ascorbate with Ribose: Promising Therapeutic Approach for Melanoma Treatment

While surgery is the definitive treatment for early-stage melanoma, the current therapies against advanced melanoma do not yet provide an effective, long-lasting control of the lesions and a satisfactory impact on patient survival. Thus, research is also focused on novel treatments that could potentiate the current therapies. In the present study, we evaluated the effect of potassium ascorbate with ribose (PAR) treatment on the human melanoma cell line, A375, in 2D and 3D models. In the 2D model, in line with the current literature, the pharmacological treatment with PAR decreased cell proliferation and viability. In addition, an increase in Connexin 43 mRNA and protein was observed. This novel finding was confirmed in PAR-treated melanoma cells cultured in 3D, where an increase in functional gap junctions and a higher spheroid compactness were observed. Moreover, in the 3D model, a remarkable decrease in the size and volume of spheroids was observed, further supporting the treatment efficacy observed in the 2D model. In conclusion, our results suggest that PAR could be used as a safe adjuvant approach in support to conventional therapies for the treatment of melanoma.

The burden of cutaneous melanoma and status of preventive measures in Central and South America

RATIONALE AND OBJECTIVE

Very little is known about the burden of cutaneous melanoma in Central and South America, despite the existence of a reasonable amount of population-based data. We present data on melanoma incidence calculated in a standardized way for Central and South America, as well as an overview of primary and secondary prevention issues in the region.

METHODS

Cancer registry data on all incident cases reported in the different registries present in Central and South America were combined to provide registry-based country estimates of age-standardized, sex-specific cutaneous melanoma incidence overall, and by histological subtype and anatomical site. A literature search provided additional information.

RESULTS

Age-standardized incidence rates were between 1 and 5 per 100,000 and tended to be higher further away from the equator. Cutaneous melanomas of the acral type, mostly occurring on the lower limbs, are a distinguishing feature of melanoma in Central and South America in comparison with high-incidence areas. Several preventive measures, both primary and secondary, are in place, albeit largely without evaluation.

CONCLUSION

Due to incomplete registration and different registration practices, reliable and comparable data on melanoma were difficult to obtain; thus it is likely that the true burden of melanoma in Central and South America has been underestimated. The different characteristics of the cutaneous melanoma patient population in terms of anatomical site and histological type distribution imply a need for adapted primary and secondary prevention measures. The generally high ambient ultraviolet radiation levels require sufficient sun protection measures.

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

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

Time trends in incidence of cutaneous melanoma by detailed anatomical location and patterns of ultraviolet radiation exposure: a retrospective population-based study

Given the wide public health implications of the melanoma epidemic, ultraviolet radiation (UVR) exposure patterns contributing to cutaneous melanoma development should be clearly identified. To describe time trends of anatomic sites of melanoma using a UVR exposure model based on clothing and sun habits, we reviewed the medical records of all patients diagnosed with primary invasive melanoma or melanoma in situ (MIS) during the years 1977-78, 1983-84, 1989-90, 1995-96, and 2000-01 (n=3058) in one healthcare region of Sweden. Age-standardized incidence rates and relative risks (RRs) of melanoma by calendar period were estimated for intermittent and chronic UVR exposure sites. From 1977-78 to 2000-01, the incidence rates of all melanomas at intermittent UVR exposure sites increased both among men (7.8-16.5/10 person-years) and among women (7.6-14.6/10 person-years), with a sex-adjusted and age-adjusted RR of 2.1 [95% confidence interval (CI) 1.8-2.4, Ptrend<0.0001]. This increase was evident for both invasive melanoma and MIS. Melanoma at chronic sites increased among men from 1.7 to 2.3/10 person-years, and among women from 1.4 to 1.8/10 person-years, with a corresponding adjusted RR of 1.4 (95% CI 1.0-1.9, Ptrend=0.01), driven primarily by MIS. For melanomas at intermittent UVR exposure sites, the male sex was positively associated with central (core) areas (chest, back, neck, shoulders, thighs; RR 1.7, 95% CI 1.5-1.9), but negatively associated with peripheral areas (lateral arms, lower legs, dorsum of feet; RR 0.3, 95% CI 0.3-0.4), compared with the female sex. Sex-specific intermittent UVR exposure patterns drove the observed increase in melanoma incidence, whereas chronic UVR exposure contributed less.

Epidemiological aspects of melanoma at a university hospital dermatology center over a period of 20 years

BACKGROUND

The incidence of melanoma has been steadily rising in past decades. Although it accounts for only 3% of all skin cancers, it is responsible for 75% of deaths.

OBJECTIVE

to describe the epidemiological aspects of melanoma in a university hospital setting over a period of 20 years.

METHODS

A total of 166 patients were analyzed between January 1990 and January 2010 for clinical and histological variables and correlations between them. A 5% level of significance was adopted.

RESULTS

The majority of patients were Caucasians (74%), females (61%), with a mean age at diagnosis of 55. The predominant histological type was lentigo maligna/lentigo maligna melanoma (35.7%) and the head and neck was the most affected site (30.7%). Among non-Caucasians, the acral region was the most affected. Most tumors were in situ (41.1%). Growth of the lesion was the most frequent complaint (58.1%) and bleeding was most frequently associated with melanomas with a depth > 4mm. There were seven deaths (4.2%), with a high risk among men, non-Caucasians and those under 20 years of age, with a Breslow's depth > 2mm, with lentiginous acral melanoma and with a history of growth and bleeding.

CONCLUSIONS

Our sample differs from most of the studies in the predominant location (head and neck), histological type (lentigo maligna/ lentigo maligna melanoma) and a major risk of death under the age of 20, which could be with a reflex of regional variation. Broader studies are necessary for validation of the results.

Multicenter case-control study of risk factors for cutaneous melanoma in Valencia, Spain

INTRODUCTION

It is important to identify subgroups within the general population that have an elevated risk of developing cutaneous melanoma because preventive and early-detection measures are useful in this setting. The findings of most studies that have evaluated risk factors for cutaneous melanoma are of limited application in Spain because the populations studied have different pigmentary traits and are subject to different environmental factors.

OBJECTIVE

To identify the phenotypic characteristics and amount of exposure to sunlight that constitute risk factors for cutaneous melanoma in the population of the Autonomous Community of Valencia, Spain.

METHODS

We performed a multicenter observational case-control study. In total, the study included 242 patients with melanoma undergoing treatment in 5 hospitals and 173 controls enrolled from among the companions of the patients between January 2007 and June 2008. The information was collected by means of a standardized, validated questionnaire. The odds ratio (OR) was calculated for each variable and adjusted using a multiple logistic regression model.

RESULTS

The risk factors found to be statistically significant were skin phototypes I and II, blond or red hair, light eye color, abundant melanocytic nevi, and a personal history of actinic keratosis or nonmelanoma skin cancer. After the multivariate analysis, only blond or red hair (OR=1.9), multiple melanocytic nevi (OR=3.1), skin phototypes i and ii (OR=2.1), and a personal history of actinic keratosis (OR=3.5) or nonmelanoma skin cancer (OR=8.1) maintained significance in the model as independent predictive variables for melanoma.

CONCLUSIONS

Our study supports the importance of certain factors that indicate genetic predisposition (hair color and skin phototype) and environmental factors associated with exposure to sunlight. Patients with multiple acquired melanocytic nevi and patients with markers of chronic skin sun damage (actinic keratosis and nonmelanoma cancer) presented a significant increase in risk.

Ethnicity and cutaneous melanoma in the city of Sao Paulo, Brazil: a case-control study

BACKGROUND

Over the last century the incidence of cutaneous melanoma has increased worldwide, a trend that has also been observed in Brazil. The identified risk factors for melanoma include the pattern of sun exposure, family history, and certain phenotypic features. In addition, the incidence of melanoma might be influenced by ethnicity. Like many countries, Brazil has high immigration rates and consequently a heterogeneous population. However, Brazil is unique among such countries in that the ethnic heterogeneity of its population is primarily attributable to admixture. This study aimed to evaluate the contribution of European ethnicity to the risk of cutaneous melanoma in Brazil.

METHODOLOGY/PRINCIPAL FINDINGS

We carried out a hospital-based case-control study in the metropolitan area of Sao Paulo, Brazil. We evaluated 424 hospitalized patients (202 melanoma patients and 222 control patients) regarding phenotypic features, sun exposure, and number of grandparents born in Europe. Through multivariate logistic regression analysis, we found the following variables to be independently associated with melanoma: grandparents born in Europe-Spain (OR = 3.01, 95% CI: 1.03-8.77), Italy (OR = 3.47, 95% CI: 1.41-8.57), a Germanic/Slavic country (OR = 3.06, 95% CI: 1.05-8.93), or ≥ 2 European countries (OR = 2.82, 95% CI: 1.06-7.47); eye color-light brown (OR = 1.99, 95% CI: 1.14-3.84) and green/blue (OR = 4.62; 95% CI 2.22-9.58); pigmented lesion removal (OR = 3.78; 95% CI: 2.21-6.49); no lifetime sunscreen use (OR = 3.08; 95% CI: 1.03-9.22); and lifetime severe sunburn (OR = 1.81; 95% CI: 1.03-3.19).

CONCLUSIONS

Our results indicate that European ancestry is a risk factor for cutaneous melanoma. Such risk appears to be related not only to skin type, eye color, and tanning capacity but also to others specific characteristics of European populations introduced in the New World by European immigrants.

Skin cancer education and early detection at the beach: a randomized trial of dermatologist examination and biometric feedback

BACKGROUND

There are limited data on the effectiveness of skin cancer prevention education and early detection programs at beaches.

OBJECTIVES

We evaluate 4 strategies for addressing skin cancer prevention in beach settings.

METHODS

This prospective study at 4 beaches included 4 intervention conditions: (1) education only; (2) education plus biometric feedback; (3) education plus dermatologist skin examination; or (4) education plus biometric feedback and dermatologist skin examination. Outcomes included sun protection behaviors, sunburns, and skin self-examinations.

RESULTS

There was a significant increase in hat wearing, sunscreen use, and a reduction in sunburns in the education plus biometric feedback group (odds ratio = 1.97, 1.94, and 1.07, respectively), and greater improvements in knowing what to look for in skin-self examinations (odds ratio = 1.13); there were no differences in frequency of self-examinations. Skin examinations plus biometric feedback led to greater reductions in sunburns. The dermatologist examinations identified atypical moles in 28% of participants.

LIMITATIONS

Inclusion of only one beach per condition, use of self-report data, and a limited intervention period are limitations.

CONCLUSIONS

Education and biometric feedback may be more effective than education alone for impacting sun protective attitudes and behaviors in beachgoing, high-risk populations.

Estimating the attributable fraction for melanoma: a meta-analysis of pigmentary characteristics and freckling

Epidemiologic research has demonstrated convincingly that certain pigmentary characteristics are associated with increased relative risks of melanoma; however there has been no comprehensive review to rank these characteristics in order of their importance on a population level. We conducted a systematic review of the literature and meta-analysis to quantify the contribution of pigmentary characteristics to melanoma, estimated by the population-attributable fraction (PAF). Eligible studies were those that permitted quantitative assessment of the association between histologically confirmed melanoma and hair colour, eye colour, skin phototype and presence of freckling; we identified 66 such studies using citation databases, followed by manual review of retrieved references. We calculated summary relative risks using weighted averages of the log RR, taking into account random effects, and used these to estimate the PAF. The pooled RRs for pigmentary characteristics were: 2.64 for red/red-blond, 2.0 for blond and 1.46 for light brown hair colour (vs. dark); 1.57 for blue/blue-grey and 1.51 for green/grey/hazel eye colour (vs. dark); 2.27, 1.99 and 1.35 for skin phototypes I, II and III respectively (vs. IV); and 1.99 for presence of freckling. The highest PAFs were observed for skin phototypes 1/II (0.27), presence of freckling (0.23), and blond hair colour (0.23). For eye colour, the PAF for blue/blue-grey eye colour was higher than for green/grey/hazel eye colour (0.18 vs. 0.13). The PAF of melanoma associated with red hair colour was 0.10. These estimates of melanoma burden attributable to pigmentary characteristics provide a basis for designing prevention strategies for melanoma.

Indoor tanning and risk of melanoma: a case-control study in a highly exposed population

BACKGROUND

Indoor tanning has been only weakly associated with melanoma risk; most reports were unable to adjust for sun exposure, confirm a dose-response, or examine specific tanning devices. A population-based case-control study was conducted to address these limitations.

METHODS

Cases of invasive cutaneous melanoma, diagnosed in Minnesota between 2004 and 2007 at ages 25 to 59, were ascertained from a statewide cancer registry; age-matched and gender-matched controls were randomly selected from state driver's license lists. Self-administered questionnaires and telephone interviews included information on ever use of indoor tanning, types of device used, initiation age, period of use, dose, duration, and indoor tanning-related burns. Odds ratios (OR) and 95% confidence intervals (CI) were adjusted for known melanoma risk factors.

RESULTS

Among 1,167 cases and 1,101 controls, 62.9% of cases and 51.1% of controls had tanned indoors (adjusted OR 1.74; 95% CI, 1.42-2.14). Melanoma risk was pronounced among users of UVB-enhanced (adjusted OR, 2.86; 95% CI, 2.03-4.03) and primarily UVA-emitting devices (adjusted OR, 4.44; 95% CI, 2.45-8.02). Risk increased with use: years (P < 0.006), hours (P < 0.0001), or sessions (P = 0.0002). ORs were elevated within each initiation age category; among indoor tanners, years used was more relevant for melanoma development.

CONCLUSIONS

In a highly exposed population, frequent indoor tanning increased melanoma risk, regardless of age when indoor tanning began. Elevated risks were observed across devices.

IMPACT

This study overcomes some of the limitations of earlier reports and provides strong support for the recent declaration by the IARC that tanning devices are carcinogenic in humans.

Creation and test of a questionnaire for self-assessment of melanoma risk factors

The objective of this study was to create a self-administrated questionnaire for people to enable them to assess their own melanoma risk factors. To test the validity of this questionnaire in a large prospective study, the answers given by the patient were systematically checked by his or her general practitioner. In this prospective study, the choice of questions was based on a review of the literature. The validity of the questionnaire was assessed by testing 1500 consecutive patients attending a consultation with their general practitioner. Considerable variations concerning the prevalence of different melanoma risk factors were noticed in the population: 44.1% had a phototype I or II, 41% had severe sunburn during infancy, 29.9% had freckling tendency, 22% had more than 50 naevi and 1.4% a personal history of melanoma. In total, 45% had more than one melanoma risk factor. The accuracy of the answers given by the patients was assured by the correction given by their general practitioners. The percentage of correct answers given by the patients was 79.9% for the phototype, 90.6% for freckling tendency, 86.6% for the number of naevi, 96.5% for severe sunburn during infancy and 98.1 and 95.8% for personal and familial history of melanoma. This study confirms that individuals with multiple risk factors for melanoma are common among patients consulting their general practitioners. Furthermore, self-screening with the self-assessment questionnaire is easily feasible and is accurate for identifying high-risk individuals. This tool might be useful for carrying out melanoma-targeted screening.

Familial melanoma: a meta-analysis and estimates of attributable fraction

Melanoma commonly clusters in families, and the recent identification of numerous genotypes predicting higher risks of melanoma has led to the widespread perception that this cancer is predominantly a genetic disease. We conducted a systematic review of the literature and meta-analysis to quantify the contribution of familial factors to melanoma, estimated by the population attributable fraction (PAF). Eligible studies were those that permitted quantitative assessment of the association between histologically confirmed melanoma and family history of the disease; we identified 22 such studies using citation databases, followed by manual review of retrieved references. We calculated summary RRs using weighted averages of the log RR, taking into account random effects, and used these to estimate the PAF. Overall, family history was associated with a significant 2-fold increased risk of melanoma (odds ratio, 2.06; 95% confidence interval, 1.72-2.45); however, there was significant heterogeneity (P = 0.01). The pooled estimate for population-based studies (n = 11) was 2.03 (1.70-2.43), and 2.51 (1.55-4.07) for clinic/hospital-based studies (n = 11), both with significant heterogeneity (P = 0.049 and P = 0.013, respectively). Two studies used record linkage to verify family history in relatives; the pooled risk estimate from these two studies was 2.52 (2.11-3.00) with no evidence of heterogeneity (P = 0.258). Estimates of PAF associated with a positive family history ranged from 0.007 for Northern Europe to 0.064 for Australia (0.040 for all regions combined). Our findings suggest that only a small percentage of melanoma cases (always <7%) are attributable to familial risk; the majority of melanomas are presumably attributable to other factors.

Estimating the attributable fraction for cancer: A meta-analysis of nevi and melanoma

Epidemiologic research has shown convincingly that certain phenotypic attributes are associated with increased relative risks of melanoma. Although such findings have intrinsic utility, there have been few attempts to translate such knowledge into estimates of disease burden suitable for framing public health policy. We aimed to estimate the population attributable fraction (PAF) for melanoma associated with melanocytic nevi using relative risk estimates derived from a systematic review and meta-analysis. We identified eligible studies using citation databases, followed by manual review of retrieved references. Of 49 studies identified, 25 and 23, respectively, were included in meta-analyses of atypical and common nevi. For people with > or =1 atypical nevi, the summary relative risk was 3.63 (95% confidence interval, 2.85-4.62), with a PAF of 0.25. The relative risk increased by 1.017 (95% confidence interval, 1.014-1.020) for each common nevus; however, significant heterogeneity in risk estimates was observed. We estimated that 42% of melanomas were attributable to having > or =25 common nevi (PAF 25-49 nevi = 0.15; PAF > or =50 nevi = 0.27), whereas PAFs for low nevus counts were modest (PAF 0-10 nevi = 0.04; PAF 11-24 nevi = 0.07). We modeled PAF under scenarios of varying nevus prevalence; the highest melanoma burden was always among those with high nevus counts (PAF range of 0.31-0.62 for > or =25 common nevi). Patients with > or =25 common nevi and/or > or =1 atypical nevi are a high-risk group, which might be targeted for identification, screening, and education. This work is the necessary first step in designing targeted preventive strategies for melanoma, which must now be overlaid with information about cost and utility.

Sunburns and risk of cutaneous melanoma: does age matter? A comprehensive meta-analysis

PURPOSE

Sunburns are an important risk factor for melanoma and those occurring in childhood are often cited as posing the greatest risk. We conducted a meta-analysis to quantify the magnitude of association for melanoma and sunburns during childhood, adolescence, adulthood and over a lifetime.

METHODS

After reviewing over 1300 article titles and evaluating 270 articles in detail, we pooled odds ratios from 51 independent study populations for "ever" sunburned and risk of cutaneous melanoma. Among these, 26 studies reported results from dose-response analyses. Dose-response analyses were examined using both fixed-effects models and Bayesian random-effects models.

RESULTS

An increased risk of melanoma was seen with increasing number of sunburns for all time-periods (childhood, adolescence, adulthood, and lifetime). In an attempt to understand how risk between life-periods compares, we also report these same linear models on a scale of five sunburns per decade for each life-period. The magnitude of risk for five sunburns per decade is highest for adult and lifetime sunburns.

CONCLUSIONS

Overall, these results show an increased risk of melanoma with increasing number of sunburns during all life-periods, not just childhood. Prevention efforts should focus on reducing sunburns during all life-periods.

Cutaneous melanoma and obesity in the Agricultural Health Study

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Photoprotection

Sun exposure is the main cause of photocarcinogenesis, photoageing, and photosensitivity; thus, photoprotection is an important issue. In a skin cancer prevention strategy, behavioural measures--eg, wearing sun protective clothes and a hat and reducing sun exposure to a minimum--should be preferred to sunscreens. Often this solution is deemed to be unacceptable in our global, outdoor society, and sunscreens could become the predominant mode of sun protection for various societal reasons (eg, healthiness of a tan, relaxation in the sun). The application of a liberal quantity of sunscreen has been shown to be by far the most important factor for effectiveness of the sunscreen, followed by the uniformity of application and the specific absorption spectrum of the agent used. The sunscreen market--crowded by numerous products--shows various differences worldwide. Nevertheless, sunscreens should not be abused in an attempt to increase time in the sun to a maximum. Controversies about safety of sunscreens and clinical recommendations are discussed.

Ambient UVB and melanoma risk in the United States: a case-control analysis

PURPOSE

Exposure to ultraviolet-B (UVB) radiation is a well-established risk factor for human cutaneous malignant melanoma. Intermittent and cumulative exposures from UVB have been estimated most often by interview questionnaire. This study assessed cumulative UVB using a ground-based measurement instrument to estimate the association between UVB and melanoma.

METHODS

Population-based, incident cases of melanoma (n = 380) and frequency-matched controls (n = 364) residing in Connecticut at diagnosis were interviewed between 1987 and 1989 about recreational and vacation activities, sun-protection practices, occupation, and other factors. Using a residential history, regression estimates of lifetime UVB were derived from ambient measures of UVB, adjusted for intermittent exposure.

RESULTS

Cases and controls received 29% of lifetime mean UVB in the first 15 years of life. Number of days per year in recreational activity during childhood and late adulthood were associated with increased melanoma risk. When estimating lifetime UVB adjusted for intermittent exposure, melanoma risk peaked at a 5.7-fold increased risk in the ninth decile.

CONCLUSION

Sporadic and chronic sun exposure play a role in melanoma etiology. Skin-protection practices should be encouraged across levels of sun intensity, not only in childhood but throughout adulthood.

Queimaduras e hábitos solares em um grupo de atletas brasileiros

INTRODUÇÃO E OBJETIVOS: As queimaduras solares são consideradas o principal fator de risco ambiental para o melanoma, principalmente quando antes dos 20 anos de idade. Atletas profissionais são, em sua maioria, jovens que se expõem ao sol com bastante intensidade, tanto em suas atividades quanto no lazer, tornando-se um grupo susceptível às queimaduras. O estudo visa avaliar os conhecimentos e hábitos de proteção solar de um grupo de atletas brasileiros. MÉTODOS: Cento e quinze atletas brasileiros, durante os XIV Jogos Pan-Americanos, responderam a um questionário sobre queimaduras solares nos treinamentos e lazer, fototipo, uso de filtros solares (UFS) e conhecimento da importância de se proteger do sol (IPS) e local da prática (outdoor x indoor). RESULTADOS: A maioria era outdoor (73%) e 59% possuíam fototipo claro (I, II ou III). Quanto ao seu local de prática, os outdoor apresentaram índices superiores de queimaduras solares, IPS e UFS durante seus treinamentos, enquanto no lazer os grupos não se diferenciaram. Divididos por fototipo, os grupos de atletas mais claros apresentaram mais queimaduras solares, tanto em treinamentos quanto no lazer. Na análise multivariada para avaliação de risco de queimaduras solares, os fototipos claros e a IPS demonstraram-se estatisticamente significativos. CONCLUSÕES: Esportes realizados ao ar livre geram mais queimaduras solares nos atletas que os praticam. Entretanto, quando em tempo de lazer, atletas outdoor e indoor possuem hábitos solares semelhantes, mostrando que neste momento formam um grupo homogêneo com relação à fotoexposição. Atletas com fototipos claros são mais propensos a queimaduras, tanto no lazer quanto nos treinamentos. As taxas de uso de filtros solares são inferiores ao desejado. É necessário estimular a fotoproteção nos atletas, tanto nas suas atividades desportivas quanto no lazer.

Melanoma, Parkinson's disease and levodopa: causal or spurious link? A review of the literature

Since the early 1970s, a number of case reports have suggested that levodopa therapy for Parkinson's disease increases the risk of cutaneous malignant melanoma. As yet, no formal epidemiological study has been conducted to verify this hypothesis. To elucidate the relationship between levodopa and the risk of cutaneous malignant melanoma, a systematic literature search using computerized bibliographic databases was done. This review presents the case history evidence for and against the hypothesis of a causal association, and explores possible epidemiological, genetic, social, biochemical and toxicological factors that may increase the risk of melanoma in Parkinson's disease patients. All the case reports in the literature were considered. We concluded that (1) there is no epidemiological or experimental evidence of a causal role of levodopa in increasing the risk of melanoma incidence or progression; (2) there is good evidence of an excess risk of melanoma in patients with Parkinson's disease; (3) there is good evidence of a protective effect of tobacco smoking on the risk for Parkinson's disease; (4) there is good evidence of positive correlation between social class and melanoma risk; (5) the relationship between the risk of Parkinson's disease and the risk of melanoma may be due to a common genetic profile or it can be attributed to a confounding role of social class, associated with both melanoma and Parkinson's disease possibly through an inverse relationship with tobacco smoking.

Meta-analysis of risk factors for cutaneous melanoma: III. Family history, actinic damage and phenotypic factors

A systematic meta-analysis of observational studies of melanoma and family history, actinic damage and phenotypic factors was conducted as part of a comprehensive meta-analysis of all major risk factors for melanoma. Following a systematic literature search, relative risks were extracted from 60 studies published before September 2002. Fixed and random effects models were used to obtain pooled estimates for family history (RR = 1.74, 1.41-2.14), skin type (I vs. IV: RR = 2.09, 1.67-2.58), high density of freckles (RR = 2.10, 1.80-2.45), skin colour (Fair vs. Dark: RR = 2.06, 1.68-2.52), eye colour (Blue vs. Dark: RR = 1.47, 1.28-1.69) and hair colour (Red vs. Dark: RR = 3.64, 2.56-5.37), pre-malignant and skin cancer lesions (RR = 4.28, 2.80-6.55) and actinic damage indicators (RR = 2.02, 1.24-3.29). Sub-group analysis and meta-regression were carried out to explore sources of between-study variation and bias. Sensitivity analyses investigated reliability of results and publication bias. Latitude and adjustment for phenotype were two study characteristics that significantly influenced the estimates.

Pediatric Melanoma: Risk Factor and Survival Analysis of the Surveillance, Epidemiology and End Results Database

Purpose

To evaluate risk factors for the development of and factors influencing survival in pediatric melanoma.

Patients and Methods

We evaluated 1,255 children (age < 20 years) and 2,673 young adults (age 20 to 24 years) with melanoma in the 2001 National Cancer Institute (NCI) Surveillance, Epidemiology and End Results (SEER) database. We estimated exposure to UV radiation based on Environmental Protection Agency (EPA) measurements.

Results

The incidence of pediatric melanoma increased 46% (95% CI, 40 to 52) per year of age and 2.9% (95% CI, 2.1 to 3.6) per year from 1973 to 2001. Incidence rates were lower in black patients (−95%; 95% CI, −98 to −90) compared with white patients and in male patients (−39%; 95% CI −46 to −31) compared with females. Increased ambient UV radiation was associated with elevated risk (19% per kJ; 95% CI, 9 to 30). Children with melanoma had a 5-year melanoma-specific survival of 93.6% (95% CI, 91.9 to 94.9), which improved from 1973 to 2001. The hazard ratio of death from melanoma increased with male sex; older age; advanced disease; location of the primary other than extremities or torso; earlier year of diagnosis; and previous cancer.

Conclusion

The incidence of melanoma in the United States is increasing rapidly in children. Risk factors for pediatric melanoma include being white, being female, increasing age, and environmental UV radiation. Survival is decreased for children and adolescents with unfavorable prognostic factors (male sex, unfavorable site, and/or second primary or regional or distant metastasis). More effective therapeutic strategies are needed for these groups.

[Malignant melanoma -- a medical students' viewpoint]

Malignant melanoma is a primarily cutaneous melanocytic tumour with increasing incidence responsible for 90 % of skin cancer mortality. Genetic predisposition has been identified as the most important risk factor, while UV is second in importance and can be avoided. New diagnostic methods include sentinel lymph node biopsy and the detection of tumour markers in blood. Furthermore, malignant melanoma shows an extraordinary resistance to therapy; at present the only cure lies in early excision of the primary tumour. Thus early recognition is of utmost importance. Experimental approaches, such as dendritic cell vaccination, have shown some effectiveness which must be confirmed in multicenter, randomised trials.

Site-specific protective effect of broad-spectrum sunscreen on nevus development among white schoolchildren in a randomized trial

BACKGROUND

Melanocytic nevus density is a strong risk factor for cutaneous malignant melanoma. Reducing the number of nevi in children may reduce the risk of their developing melanoma as adults.

OBJECTIVE

We sought to assess the effect of sunscreen use on nevus development by anatomic sites and by nevi of different sizes for white schoolchildren in a randomized trial.

METHODS

We compared the new nevus count between the sunscreen intervention group (n = 145) and the control group (n = 164) by anatomic site.

RESULTS

Children randomized to the sunscreen group had significantly fewer new nevi on the trunk than children in the control group. The differences were more pronounced among the freckled children than children with no freckles.

LIMITATIONS

Potential limitations to this study include relatively small numbers of enrolled children, and a follow-up period of only 3 years.

CONCLUSION

Sunscreen use attenuated new nevus development on intermittently sun-exposed body sites for white schoolchildren, particularly among the freckled children.

Meta-analysis of risk factors for cutaneous melanoma: II. Sun exposure

A systematic revision of the literature was conducted in order to undertake a comprehensive meta-analysis of all published observational studies on melanoma. An extensive analysis of the inconsistencies and variability in the estimates was performed to provide some clues about its Epidemiology. Following a systematic literature search, relative risks (RRs) for sun exposure were extracted from 57 studies published before September 2002. Intermittent sun exposure and sunburn history were shown to play considerable roles as risk factors for melanoma, whereas a high occupational sun exposure seemed to be inversely associated to melanoma. The country of study and adjustment of the estimates adjuste for phenotype and photo-type were significantly associated with the variability of the intermittent sun exposure estimates (P = 0.024, 0.003 and 0.030, respectively). For chronic sun exposure, inclusion of controls with dermatological diseases and latitude resulted in significantly different data (P = 0.05 and 0.031, respectively). Latitude was also shown to be important (P = 0.031) for a history of sunburn; studies conducted at higher latitudes presented higher risks for a history of sunburns. Role of country, inclusion of controls with dermatological diseases and other study features seemed to suggest that "well conducted" studies supported the intermittent sun exposure hypothesis: a positive association for intermittent sun exposure and an inverse association with a high continuous pattern of sun exposure.

Constitutional and environmental risk factors for cutaneous melanoma in an Italian population. A case-control study

The aim of this study was to determine the relative risk for cutaneous melanoma associated with phenotypic and environmental variables in a population in central Italy and to assess how the combination of the different risk factors contributes to the overall risk for melanoma. We performed a case-control study of 100 patients with sporadic cutaneous melanoma and 200 controls matched for sex, age, ethnicity and residential area. Individuals were interviewed concerning pigmentary traits and sun exposure, and underwent a total body skin examination. Logistic regression models were used to evaluate the association between cutaneous melanoma and constitutional and environmental variables. The strongest risk factors were prolonged recreational sun exposure (odds ratio [OR] 5.010, 95% confidence interval [CI] 2.110-11.891), the presence of clinically atypical naevi (OR 4.916, 95% CI 2.496-9.995) and the presence of >50 common melanocytic naevi (OR 4.684, 95% CI 2.442-9.231). In addition, occupational sun exposure (OR 2.573, 95% CI 1.399-4.732), light brown hair (OR 2.336, 95% CI 1.328-4.138), high density of solar lentigos and/or actinic keratoses (OR 1.824, 95% CI 1.0-3.510) and type II, fair skin (OR 1.815, 95% CI 1.031-3.193) and blue eyes (OR 1.757, 95% CI 1.0-3.477) were each significantly associated with cutaneous melanoma risk. The combination of individual strong risk factors was associated with up to a 46-fold increase in the risk for cutaneous melanoma. Selected pigmentary traits, sun exposure and melanocytic naevi, individually and in combination, are important risk factors for cutaneous melanoma in an Italian population.

Meta-analysis of risk factors for cutaneous melanoma: I. Common and atypical naevi

A systematic meta-analysis of observational studies of melanoma and one of the most important risk factors, the number of naevi, was conducted in order to clarify aspects of the aetiology of this disease. Following a systematic literature search, relative risks (RRs) were extracted from 46 studies published before September 2002. Dose-response random effects models were used to obtain pooled estimates. Sub-group analysis and meta-regression were carried out to explore sources of between-study variation and bias. Sensitivity analyses investigated the reliability of the results and any publication bias. Number of common naevi was confirmed an important risk factor with a substantially increased risk associated with the presence of 101-120 naevi compared with <15 (pooled Relative Risk (RR) = 6.89; 95% Confidential Interval (CI): 4.63, 10.25) as was the number of atypical naevi (RR = 6.36 95%; CI: 3.80, 10.33; for 5 versus 0). The type of study and source of cases and controls were two study characteristics that significantly influenced the estimates. Case-control studies, in particular when the hospital was the source for cases or controls, appeared to present much lower and more precise estimates than cohort studies.

Acquired melanocytic nevi as risk factor for melanoma development. A comprehensive review of epidemiological data

Acquired melanocytic nevi (MN) in Caucasian populations are important markers for the risk of melanoma development. The total number of MN on the whole body is the most important independent risk factor for melanoma and the risk of melanoma development increases almost linearly with rising numbers of MN. Additionally, the presence of atypical MN and of actinic lentigines are likewise independent risk factors for melanoma. Atypical mole syndrome should be defined by the presence of many acquired MN and a threshold number of atypical MN. Acquired MN develops mainly during childhood and adolescence in the first two decades of life. The number of acquired nevi seems to be related to hereditary factors and nevus-prone families exist. The amount of sun exposure is the most important environmental risk factor for nevus development, particularly in early childhood. Interestingly, sunburns may play a role in nevus development, but seem not to be required, and even moderate sun exposure promotes the process. Therefore, preventive measures for nevus and melanoma development should target young children and adolescents.