Risk of cutaneous melanoma associated with pigmentation characteristics and freckling: systematic overview of 10 case-control studies. The International Melanoma Analysis Group (IMAGE)

Genome wide association study and meta-analysis identified multiple new risk loci for freckles in 4813 Chinese individuals

Freckle is a prevalent pigmentary dermatosis with an obvious hereditary component. Dozens of freckles risk loci have been discovered through research on multiple traits or other diseases, rather than as an independent trait. To discover novel variants associated with freckles, we performed GWAS and meta-analysis in 4813 Chinese individuals. We conducted GWAS and meta-analysis of two cohorts: 197 patients and 1603 controls (Cohort I), and 336 patients and 2677 controls (Cohort II), both from China. Then we performed linkage disequilibrium (LD) analysis, eQTL study, and enrichment analysis with association results for functional implications. Finally, we discovered 59 new SNPs and 13 novel susceptibility genes associated with freckles (Pmeta <5 × 10-8), which has enriched the genetic research on freckles.

Cutaneous melanoma

Cutaneous melanoma is a malignancy arising from melanocytes of the skin. Incidence rates are rising, particularly in White populations. Cutaneous melanoma is typically driven by exposure to ultraviolet radiation from natural sunlight and indoor tanning, although there are several subtypes that are not related to ultraviolet radiation exposure. Primary melanomas are often darkly pigmented, but can be amelanotic, with diagnosis based on a combination of clinical and histopathological findings. Primary melanoma is treated with wide excision, with margins determined by tumour thickness. Further treatment depends on the disease stage (following histopathological examination and, where appropriate, sentinel lymph node biopsy) and can include surgery, checkpoint immunotherapy, targeted therapy, or radiotherapy. Systemic drug therapies are recommended as an adjunct to surgery in patients with resectable locoregional metastases and are the mainstay of treatment in advanced melanoma. Management of advanced melanoma is complex, particularly in those with cerebral metastasis. Multidisciplinary care is essential. Systemic drug therapies, particularly immune checkpoint inhibitors, have substantially increased melanoma survival following a series of landmark approvals from 2011 onward.

Redheaded women are more sexually active than other women, but it is probably due to their suitors

Women with red hair color, i.e., 1–9% of female Europeans, tend to be the subject of various stereotypes about their sexually liberated behavior. The aim of the present case–control study was to explore whether a connection between red hair color and sexual behavior really exists using data from 110 women (34% redheaded) and 93 men (22% redheaded). Redheadedness in women, correlated with various traits related to sexual life, namely with higher sexual desire as measured by Revised Sociosexual Orientation Inventory, with higher sexual activity and more sexual partners of the preferred gender over the past year, earlier initiation of sexual life, and higher sexual submissiveness. Structural equation modelling, however, showed that sexual desire of redheaded women mediated neither their higher sexual activity nor their higher number of sexual partners. These results indirectly indicate that the apparently more liberated sexual behavior in redheaded women could be the consequence of potential mates’ frequent attempts to have sex with them. Our results contradicted the three other tested models, specifically the models based on the assumption of different physiology, faster life history strategy, and altered self-perception of redheaded women induced by stereotypes about them. Naturally, the present study cannot say anything about the validity of other potential models that were not subjects of testing.

Analysis of melanoma tumor antigens and immune subtypes for the development of mRNA vaccine

Melanoma has a high degree of malignancy and mortality. While there are some hopeful clinical trials for melanoma treatment in progress, they have not yet to yield significant long-term cure rates. Cancer vaccines including mRNA are currently one of the most promising strategy for tumor immunotherapy. The aim of this study was to analyze the potential tumor antigens in melanoma that could be used to develop mRNA vaccines and identify suitable vaccine populations. The gene expression data and complete clinical information of 471 melanoma samples and 1 normal tissue were retrieved from TCGA. Then, 812 samples of normal skin and their corresponding gene expression data were obtained from GTEx. Overexpressed genes, mutated genes and IRDEGs are used to identify potential tumor antigens. The relationship between the expression level of potential antigen and prognosis was analyzed in GEPIA, and then the immune cell infiltration was estimated based on TIMER algorithm. The expression profiles of IRDEGs were used to identify consensus clusters and immune subtypes of melanoma. Finally, mutational status and immune microenvironment characterization in immune subtypes were analyzed. Five tumor antigens (PTPRC, SIGLEC10, CARD11, LILRB1, ADAMDEC1) were identified as potential tumor antigens according to overexpressed genes, mutated genes and immune-related genes. They were all associated with OS, DFS and APCs. We identified two immune subtypes of melanoma, named IS1 and IS2, which exhibit different clinical features and immune landscapes. Based on the different immune landscape, we may conclude that IS1 is immunophenotypically "cold", while IS2 is "hot". The present research implicates that PTPRC, SIGLEC10, CARD11, LILRB1 and ADAMDEC1 may be the antigenic targets for melanoma mRNA vaccines and IS2 patients may be more effective to these vaccines.

The spectrum of melanocytic nevi and their clinical implications

The magnitude of the topic of melanocytic nevi (MN) is directly related to its relevance in everyday clinical work. The different MN have different prognostic significance in regard to comorbidity and possible risk of transformation. In addition to the criteria of the ABCDE rule, relevant criteria in the assessment of an MN are the time of occurrence, the growth tendency, the distribution and the comparison with other MN of the respective individual.

The present CME article provides an overview of the knowledge that has been gained with regard to the development and genetic background of MN and any risk of degeneration that may exist. In addition, certain clinical and/or dermatoscopic features may provide the clinician with a decision‐making aid in the management of different MNs.

Eye color and the risk of skin cancer

Melanoma, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common skin cancers. The incidence rates of all three types of skin cancers have increased in the past three decades. Light pigmentary traits have been recognized as one of the host risk factors for skin cancer, but findings on associations between eye colors and risk of skin cancers have been inconsistent.We performed a prospective analysis to examine the association between eye colors and risk of skin cancers using the Health Professionals Follow-up Study (HPFS). Cox proportional hazard models were applied to estimate relative risks (RRs) and their 95% confidence intervals (CIs). Effect modifications due to hair color and skin reaction to sun were also examined.The HPFS included 35,662 males. During a median follow-up of 19 years (1988-2012), 445 melanoma, 1123 SCC, and 7198 BCC cases were documented. Compared to those whose eye colors were dark or brown, participants with hazel/green/medium and blue/light colors had a 24% (RR = 1.24, 95% CI: 1.06-1.45) and a 19% (RR = 1.19, 95% CI: 1.01-1.41) higher risk of SCC, respectively. Similarly, a higher risk of BCC was observed in participants with hazel/green/medium eye colors (RR = 1.16, 95% CI: 1.09-1.23) and blue/light eye colors (RR = 1.17, 95% CI: 1.10-1.25). We did not find significant associations between eye color and risk of melanoma. Lighter eye color was associated with increased risks of SCC and BCC among those with dark hair colors (p for interaction ≤ 0.02).In conclusion, in this large prospective study of men, we found that light eye colors were associated with higher risks of SCC and BCC, but not melanoma. Further studies are needed to confirm this association in other populations.

Review of medical image recognition technologies to detect melanomas using neural networks

BACKGROUND

Melanoma is one of the most aggressive types of cancer that has become a world-class problem. According to the World Health Organization estimates, 132,000 cases of the disease and 66,000 deaths from malignant melanoma and other forms of skin cancer are reported annually worldwide ( https://apps.who.int/gho/data/?theme=main ) and those numbers continue to grow. In our opinion, due to the increasing incidence of the disease, it is necessary to find new, easy to use and sensitive methods for the early diagnosis of melanoma in a large number of people around the world. Over the last decade, neural networks show highly sensitive, specific, and accurate results.

OBJECTIVE

This study presents a review of PubMed papers including requests «melanoma neural network» and «melanoma neural network dermatoscopy». We review recent researches and discuss their opportunities acceptable in clinical practice.

METHODS

We searched the PubMed database for systematic reviews and original research papers on the requests «melanoma neural network» and «melanoma neural network dermatoscopy» published in English. Only papers that reported results, progress and outcomes are included in this review.

RESULTS

We found 11 papers that match our requests that observed convolutional and deep-learning neural networks combined with fuzzy clustering or World Cup Optimization algorithms in analyzing dermatoscopic images. All of them require an ABCD (asymmetry, border, color, and differential structures) algorithm and its derivates (in combination with ABCD algorithm or separately). Also, they require a large dataset of dermatoscopic images and optimized estimation parameters to provide high specificity, accuracy and sensitivity.

CONCLUSIONS

According to the analyzed papers, neural networks show higher specificity, accuracy and sensitivity than dermatologists. Neural networks are able to evaluate features that might be unavailable to the naked human eye. Despite that, we need more datasets to confirm those statements. Nowadays machine learning becomes a helpful tool in early diagnosing skin diseases, especially melanoma.

Pigmented Lesions

Oral pigmented lesions have a wide range of clinical presentations, some of which correlate with cutaneous pigmented lesions. This article highlights these correlates and underscores important differences that can potentially have clinical impact. Moreover, given a nonspecific presentation of an oral pigmented lesion, the article provides a reference to aid clinicians with differential diagnoses based on clinical features. This article is an overview of pigmented lesions of the oral cavity, including localized reactive pigmented lesions, neoplastic pigmented lesions, and pigmented lesions as sequelae of a systemic disease.

Overlapping genetic architecture between Parkinson disease and melanoma

Epidemiologic studies have reported inconsistent results regarding an association between Parkinson disease (PD) and cutaneous melanoma (melanoma). Identifying shared genetic architecture between these diseases can support epidemiologic findings and identify common risk genes and biological pathways. Here, we apply polygenic, linkage disequilibrium-informed methods to the largest available case-control, genome-wide association study summary statistic data for melanoma and PD. We identify positive and significant genetic correlation (correlation: 0.17, 95% CI 0.10-0.24; P = 4.09 × 10-06) between melanoma and PD. We further demonstrate melanoma and PD-inferred gene expression to overlap across tissues (correlation: 0.14, 95% CI 0.06 to 0.22; P = 7.87 × 10-04) and highlight seven genes including PIEZO1, TRAPPC2L, and SOX6 as potential mediators of the genetic correlation between melanoma and PD. These findings demonstrate specific, shared genetic architecture between PD and melanoma that manifests at the level of gene expression.

Epidemiological evidence of carcinogenicity of sunbed use and of efficacy of preventive measures

The International Agency for Research on Cancer classified, in July 2009, exposure to artificial tanning devices (sunbeds) as carcinogenic to humans. This classification was based on evidence from epidemiological and experimental animal studies. The present chapter will review these epidemiological evidences. The summary risk estimates from 27 epidemiological studies obtained through a meta-analysis showed an increased risk of melanoma: summary relative risk (SRR) = 1.20 [95% confidence interval (CI) 1.08-1.34]. The risk was higher when exposure took place at younger age (SRR = 1.59; 95% CI 1.36-1.85). The risk was independent of skin sensitivity or population and a dose response was evident. A meta-analysis of 12 studies was conducted for non-melanoma skin cancers and showed a significantly increased risk for basal cell carcinoma (SRR = 1.29; 95% CI 1.08-1.53) and for squamous cell carcinoma (SRR = 1.67; 95% CI 1.29-2.17). As for melanoma, the risk for other skin cancers increased for first exposures at young age. Epidemiological studies have gradually strengthened the evidence for a causal relationship between indoor tanning and skin cancer and they fit with prior knowledge on relationship between UV exposure and skin cancer. Additionally, several case-control studies provided consistent evidence of a positive association between use of sunbed and ocular melanoma, also with greater risk for first exposures at younger age. Preventive measures based on information on risk or by requiring parental authorization for young users proved to be inefficient in several studies. The significant impact of strong actions or total ban, such as performed in Iceland, or a total ban of sunbed use, as in Brazil or Australian states, needs to be further assessed.

Hereditary melanoma: a five-year study of Brazilian patients in a cancer referral center - phenotypic characteristics of probands and pathological features of primary tumors

BACKGROUND

Approximately five to 10% of all melanomas occur in families with hereditary predisposition and the main high-risk melanoma susceptibility gene is the CDKN2A.

OBJECTIVES

To describe, after a five-years study, the clinical data of patients (probands) from familial melanoma kindreds, and the pathological characteristics of their melanoma.

METHODS

The inclusion criteria were melanoma patients with a family history of melanoma or pancreatic cancer (first- or second-degree relatives) or patients with multiple primary melanomas (MPM).

RESULTS

A total of 124 probands were studied, where 64 were considered familial cases and 60 MPM. Mean age at diagnosis was 50 years. Our results show that the following characteristics were prevalent: skin phototype I/II (89.5%), sunburn during childhood (85.5%), total number of nevi ≥50 (56.5%), Breslow thickness ≤1.0mm (70.2%), tumors located on the trunk (53.2%) and superficial spreading melanomas (70.2%).

STUDY LIMITATIONS

Analyses of probands' relatives will be demonstrated in future publication.

CONCLUSIONS

Our findings are in agreement with previous familial melanomas reports. Fifteen new melanomas in 11 patients were diagnosed during follow up, all of which were ≤1.0 mm. This is the largest dataset of Brazilian melanoma prone kindreds to date, thus providing a complete database for future genetic studies.

FOXQ1 controls the induced differentiation of melanocytic cells

Oncogenic transcription factor FOXQ1 has been implicated in promotion of multiple transformed phenotypes in carcinoma cells. Recently, we have characterized FOXQ1 as a melanoma tumor suppressor that acts via repression of N-cadherin gene, and invasion and metastasis. Here we report that FOXQ1 induces differentiation in normal and transformed melanocytic cells at least partially via direct transcriptional activation of MITF gene, melanocytic lineage-specific regulator of differentiation. Importantly, we demonstrate that pigmentation induced in cultured melanocytic cells and in mice by activation of cAMP/CREB1 pathway depends in large part on FOXQ1. Moreover, our data reveal that FOXQ1 acts as a critical mediator of BRAFV600E-dependent regulation of MITF levels, thus providing a novel link between two major signal transduction pathways controlling MITF and differentiation in melanocytic cells.

Clinicopathological characteristics of cutaneous malignant melanoma in patients at a tertiary hospital in Macaronesia. Survival as a function of locoregional prognostic factors per the American Joint Committee on Cancer

BACKGROUND

Despite suffering high ultraviolet radiation levels, few data on malignant melanoma (MM) in Macaronesia are available.

METHODS

Observational study of cutaneous MM cases diagnosed during a period of 12 years at a tertiary hospital in Canary Islands.

RESULTS

A total of 532 patients (female/male = 1.4) with an average age of 56 years were included; 5% developed more than one MM, and 7% reported family history of MM. Phototype II (43%), dark eyes (41%), and dark hair (41%) predominated. There was a lower frequency of light-colored hair and eyes in those born in the Canary Islands. The most frequent locations of MM were on the back for men (37%) and on the lower extremities for women (35%). Among the infiltrating tumors (83%), the (median) thickness was 1.07 mm (women, 0.90 mm; men, 1.21 mm). Anatomopathological ulceration (AU) and a mitotic rate ≥1 mitosis/mm² (HMR) were recorded in 27% of patients. Patients with regional disease constituted 12% of the population. The most common stage was IA (34%). Melanoma-specific survival (MSSV) decreased significantly with thickness, presence of AU, HMR, and sentinel lymph node disease. These four variables were independent prognostic factors. The five-year MSSV varied between 100% (stage IA) and 39% (stage IIIC).

CONCLUSIONS

The characteristics of the patients were similar to those published in datasets from continental Europe, although the pigmentary features were darker in those originating from Macaronesia. The prognostic parameters described in the 7th edition of the American Joint Committee on Cancer (AJCC) independently predict MSSV in our patients.

Rare Variant, Gene-Based Association Study of Hereditary Melanoma Using Whole-Exome Sequencing

Background

Extraordinary progress has been made in our understanding of common variants in many diseases, including melanoma. Because the contribution of rare coding variants is not as well characterized, we performed an exome-wide, gene-based association study of familial cutaneous melanoma (CM) and ocular melanoma (OM).

Methods

Using 11 990 jointly processed individual DNA samples, whole-exome sequencing was performed, followed by large-scale joint variant calling using GATK (Genome Analysis ToolKit). PLINK/SEQ was used for statistical analysis of genetic variation. Four models were used to estimate the association among different types of variants. In vitro functional validation was performed using three human melanoma cell lines in 2D and 3D proliferation assays. In vivo tumor growth was assessed using xenografts of human melanoma A375 melanoma cells in nude mice (eight mice per group). All statistical tests were two-sided.

Results

Strong signals were detected for CDKN2A (Pmin = 6.16 × 10-8) in the CM cohort (n = 273) and BAP1 (Pmin = 3.83 × 10-6) in the OM (n = 99) cohort. Eleven genes that exhibited borderline association (P < 10-4) were independently validated using The Cancer Genome Atlas melanoma cohort (379 CM, 47 OM) and a matched set of 3563 European controls with CDKN2A (P = .009), BAP1 (P = .03), and EBF3 (P = 4.75 × 10-4), a candidate risk locus, all showing evidence of replication. EBF3 was then evaluated using germline data from a set of 132 familial melanoma cases and 4769 controls of UK origin (joint P = 1.37 × 10-5). Somatically, loss of EBF3 expression correlated with progression, poorer outcome, and high MITF tumors. Functionally, induction of EBF3 in melanoma cells reduced cell growth in vitro, retarded tumor formation in vivo, and reduced MITF levels.

Conclusions

The results of this large rare variant germline association study further define the mutational landscape of hereditary melanoma and implicate EBF3 as a possible CM predisposition gene.

Integrative genetic analysis suggests that skin color modifies the genetic architecture of melanoma

Melanoma is the deadliest form of skin cancer and presents a significant health care burden in many countries. In addition to ultraviolet radiation in sunlight, the main causal factor for melanoma, genetic factors also play an important role in melanoma susceptibility. Although genome-wide association studies have identified many single nucleotide polymorphisms associated with melanoma, little is known about the proportion of disease risk attributable to these loci and their distribution throughout the genome. Here, we investigated the genetic architecture of melanoma in 1,888 cases and 990 controls of European non-Hispanic ancestry. We estimated the overall narrow-sense heritability of melanoma to be 0.18 (P < 0.03), indicating that genetics contributes significantly to the risk of sporadically-occurring melanoma. We then demonstrated that only a small proportion of this risk is attributable to known risk variants, suggesting that much remains unknown of the role of genetics in melanoma. To investigate further the genetic architecture of melanoma, we partitioned the heritability by chromosome, minor allele frequency, and functional annotations. We showed that common genetic variation contributes significantly to melanoma risk, with a risk model defined by a handful of genomic regions rather than many risk loci distributed throughout the genome. We also demonstrated that variants affecting gene expression in skin account for a significant proportion of the heritability, and are enriched among melanoma risk loci. Finally, by incorporating skin color into our analyses, we observed both a shift in significance for melanoma-associated loci and an enrichment of expression quantitative trait loci among melanoma susceptibility variants. These findings suggest that skin color may be an important modifier of melanoma risk. We speculate that incorporating skin color and other non-genetic factors into genetic studies may allow for an improved understanding of melanoma susceptibility and guide future investigations to identify melanoma risk genes.

Outcomes of Melanoma In Situ Treated With Mohs Micrographic Surgery Compared With Wide Local Excision

Importance

Melanoma in situ (MIS) is increasing in incidence, and expert consensus opinion recommends surgical excision for therapeutic management. Currently, wide local excision (WLE) is the standard of care. However, Mohs micrographic surgery (MMS) is now used to treat a growing subset of individuals with MIS. During MMS, unlike WLE, the entire cutaneous surgical margin is evaluated intraoperatively for tumor cells.

Objective

To assess the outcomes of patients with MIS treated with MMS compared with those treated with WLE.

Design, Setting, and Participants

Retrospective review of a prospective database. The study cohort consisted of 662 patients with MIS treated with MMS or WLE per standard of care in dermatology and surgery (general surgery, otolaryngology, plastics, oculoplastics, surgical oncology) at an academic tertiary care referral center from January 1, 1978, to December 31, 2013, with follow-up through 2015.

Exposure

Mohs micrographic surgery or WLE.

Main Outcomes and Measures

Recurrence, overall survival, and melanoma-specific survival.

Results

There were 277 patients treated with MMS (mean [SD] age, 64.0 [13.1] years; 62.1% male) and 385 treated with WLE (mean [SD] age, 58.5 [15.6] years; P < .001 for age; 54.8% male). Median follow-up was 8.6 (range, 0.2-37) years. Compared with WLE, MMS was used more frequently on the face (222 [80.2%] vs 141 [36.7%]) and scalp and neck (23 [8.3%] vs 26 [6.8%]; P < .001). The median (range) year of diagnosis was 2008 (1986-2013) for the MMS group vs 2003 (1978-2013) for the WLE group (P < .001). Overall recurrence rates were 5 (1.8%) in the MMS group and 22 (5.7%) in the WLE group (P = .07). Mean (SD) time to recurrence after MMS was 3.91 (4.4) years, and after WLE, 4.45 (2.7) years (P = .73). The 5-year recurrence rate was 1.1% in the MMS group and 4.1% in the WLE group (P = .07). For WLE-treated tumors, the surgical margin taken was greater for tumors that recurred compared with tumors that did not recur (P = .003). Five-year overall survival for MMS was 92% and for WLE was 94% (P = .28). Melanoma-specific mortality for the MMS group was 2 vs 13 patients for the WLE group, with mean (SD) survival of 6.5 (4.8) and 6.1 (0.8) years, respectively (P = .77).

Conclusions and Relevance

No significant differences were found in the recurrence rate, overall survival, or melanoma-specific survival of patients with MIS treated with MMS compared with WLE.

"Better do not touch" and other superstitions concerning melanoma: the cross-sectional web-based survey

Introduction

To the authors’ best knowledge, there are no data regarding the prevalence of superstitions concerning melanoma among internet users.

Aim

To evaluate the prevalence and identify reasons for superstitions associated with excision of pigmented skin lesions as well as to assess the frequency of this procedure.

Material and methods

Readers of the scientific portal were invited to complete a fully anonymous e-questionnaire. After collection of questionnaires (5,154) and eliminating incomplete ones, 4,919 surveys were analysed.

Results

A total of 4,104 (83.4%) respondents have been aware that the total surgical excision is the only efficient way of melanoma treatment. This familiarity was related to increased skin cancer awareness but was not linked to regular skin self-examination. Over half of the surveyed agreed that “it is better not to touch naevi”. Moreover, 3,510 (71.3%) individuals believed that naevi located in “harmed places” may turn into melanoma.

Conclusions

Superstitions associated with surgical treatment of melanoma are widespread. Conducting educational campaigns is necessary, particularly among young people, whose dangerous tanning behaviours are important risk factors for melanoma occurrence in their later life.

The Genes and Genetics of Malignant Melanoma

Background:

Population-based studies have identified several clinical variables associated with an increased risk of developing cutaneous melanoma that include phenotype, amount of and response to sun exposure, and family history. However, these observations are of limited relevance to clinical practice as the risk associated with each factor is individually modest and the characteristics of these variables lack precision when applied to a particular individual.

Objective:

To review the literature regarding recent advances made in the understanding of the genes and genetics of clinical variables associated with an increased risk of melanoma.

Conclusion:

Variants of the MC1R (melanocortin-1 receptor) have been identified as major determinants of high-risk phenotypes, such as red hair and pale skin, and the ability to tan in response to UV exposure. Several studies also suggest that such variants may increase melanoma risk independent of their contribution to phenotype. A strong genetic basis for both nevus density and size has been demonstrated and the link between nevi and the development of MM has become better defined. Finally, germline defects in several genes involved in cell cycle regulation, namely, p16 and CDK4, have been demonstrated in many familial melanoma kindreds. This progress has introduced the prospect of genetic testing as a means of identifying a limited number of high-risk individuals who can be targeted with regular screening and education regarding UV exposure and skin self-examination. Ultimately, through rational genetic therapy targeted to correcting the underlying molecular defect, altering the natural history of melanoma development may be possible.

Gender-Based Differences and Barriers in Skin Protection Behaviors in Melanoma Survivors

Purpose. Skin protection behaviors and environmental exposure play a crucial role in the development and subsequent management of melanoma. This study investigates gender-based differences in skin protection behaviors after melanoma treatment. Methods. Patients diagnosed and surgically treated for cutaneous melanomas over the last six years in a geographically high risk area were surveyed over telephone using a standardized script. Results. Of 150 survey results obtained, there were 82 males and 68 females. Overall, 87% of participants reported skin self-examination for abnormal markings more often and 94% reported wearing skin protective clothing more often, with females being more than males. Females limited outdoor activity more often than males, 79% to 54%, p < 0.05. When outside, females sought shade more often than males, 75% to 56%, p < 0.05. However, males wore a wide brim hat more often than females, 52% to 28%, p < 0.05. Interestingly, 60% of participants reported wearing SPF 30 sunscreen less often, p < 0.05. Conclusion. Larger percentage of females adopted behavioral changes to prevent future melanoma. Those living in high risk areas and with outdoor occupations need particular attention to skin care. Population based screening should be adopted to deal with this rising public health crisis.

Melanoma Epidemiology and Prevention

The epidemiology of melanoma is complex, and individual risk depends on sun exposure, host factors, and genetic factors, and in their interactions as well. Sun exposure can be classified as intermittent, chronic, or cumulative (overall) exposure, and each appears to have a different effect on type of melanoma. Other environmental factors, such as chemical exposures-either through occupation, atmosphere, or food-may increase risk for melanoma, and this area warrants further study. Host factors that are well known to be important are the numbers and types of nevi and the skin phenotype. Genetic factors are classified as high-penetrant genes, moderate-risk genes, or low-risk genetic polymorphisms. Subtypes of tumors, such as BRAF-mutated tumors, have different risk factors as well as different therapies. Prevention of melanoma has been attempted using various strategies in specific subpopulations, but to date optimal interventions to reduce incidence have not emerged.

Alcohol consumption and risk of melanoma among women: pooled analysis of eight case-control studies

While alcohol consumption is known to increase the risk of several types of cancer, evidence regarding the association between alcohol and melanoma is inconclusive. This pooled analysis was conducted to examine total alcohol consumption (grams per day), and type of alcohol consumed (beer, wine, beer and wine combined, and liquor) in relation to melanoma among women using original data from eight completed case-control studies (1886 cases and 2113 controls), with adjustment for the potential confounding effects of sun exposure-related factors. We found a positive association with ever consuming alcohol [adjusted pooled odds ratio (pOR) 1.3, 95 % confidence interval (CI) 1.1-1.5]. Specifically the pORs were 1.4 (95 % CI 1.1-1.8) for wine, 1.1 (95 % CI 0.9-1.5) for beer and 1.2 (95 % CI 1.0-1.4) for liquor. However, the pOR for the highest fourth of consumption compared with never consumption was 1.0 (95 % CI 0.7-1.3) without evidence of a trend with increasing amount of total alcohol, or separately with amount of beer, wine or liquor consumed. Stratifying by anatomic site of lesion, number of nevi, age group, or histologic subtype did not alter these results. Although the results showed a weak positive association between ever consuming alcohol and melanoma occurrence, our findings do not provide strong support for the hypothesis that alcohol consumption plays a role in the development of melanoma in women.

Interactions between ultraviolet light and MC1R and OCA2 variants are determinants of childhood nevus and freckle phenotypes

BACKGROUND

Melanocytic nevi (moles) and freckles are well known biomarkers of melanoma risk, and they are influenced by similar UV light exposures and genetic susceptibilities to those that increase melanoma risk. Nevertheless, the selective interactions between UV exposures and nevus and freckling genes remain largely undescribed.

METHODS

We conducted a longitudinal study from ages 6 through 10 years in 477 Colorado children who had annual information collected for sun exposure, sun protection behaviors, and full body skin exams. MC1R and HERC2/OCA2 rs12913832 were genotyped and linear mixed models were used to identify main and interaction effects.

RESULTS

All measures of sun exposure (chronic, sunburns, and waterside vacations) contributed to total nevus counts, and cumulative chronic exposure acted as the major driver of nevus development. Waterside vacations strongly increased total nevus counts in children with rs12913832 blue eye color alleles and facial freckling scores in those with MC1R red hair color variants. Sunburns increased the numbers of larger nevi (≥2 mm) in subjects with certain MC1R and rs12913832 genotypes.

CONCLUSIONS

Complex interactions between different UV exposure profiles and genotype combinations determine nevus numbers and size, and the degree of facial freckling.

IMPACT

Our findings emphasize the importance of implementing sun-protective behavior in childhood regardless of genetic make-up, although children with particular genetic variants may benefit from specifically targeted preventive measures to counteract their inherent risk of melanoma. Moreover, we demonstrate, for the first time, that longitudinal studies are a highly powered tool to uncover new gene-environment interactions that increase cancer risk.

Toward improved public health outcomes from urban nature

There is mounting concern for the health of urban populations as cities expand at an unprecedented rate. Urban green spaces provide settings for a remarkable range of physical and mental health benefits, and pioneering health policy is recognizing nature as a cost-effective tool for planning healthy cities. Despite this, limited information on how specific elements of nature deliver health outcomes restricts its use for enhancing population health. We articulate a framework for identifying direct and indirect causal pathways through which nature delivers health benefits, and highlight current evidence. We see a need for a bold new research agenda founded on testing causality that transcends disciplinary boundaries between ecology and health. This will lead to cost-effective and tailored solutions that could enhance population health and reduce health inequalities.

Molecular pathology of skin neoplasms of the head and neck

CONTEXT

Skin neoplasms include the most common malignancies affecting humans. Many show an ultraviolet (UV)-induced pathogenesis and often affect the head and neck region.

OBJECTIVE

To review literature on cutaneous neoplasms that show a predilection for the head and neck region and that are associated with molecular alterations.

DATA SOURCES

Literature review.

CONCLUSIONS

Common nonmelanoma skin cancers, such as basal and squamous cell carcinomas, show a UV-induced pathogenesis. Basal cell carcinomas are characterized by molecular alterations of the Hedgehog pathway, affecting patched and smoothened genes. While squamous cell carcinomas show UV-induced mutations in several genes, driver mutations are only beginning to be identified. In addition, certain adnexal neoplasms also predominantly affect the head and neck region and show interesting, recently discovered molecular abnormalities, or are associated with hereditary conditions whose molecular genetic pathogenesis is well understood. Furthermore, recent advances have led to an increased understanding of the molecular pathogenesis of melanoma. Certain melanoma subtypes, such as lentigo maligna melanoma and desmoplastic melanoma, which are more often seen on the chronically sun-damaged skin of the head and neck, show differences in their molecular signature when compared to the other more common subtypes, such as superficial spreading melanoma, which are more prone to occur at sites with acute intermittent sun damage. In summary, molecular alterations in cutaneous neoplasms of the head and neck are often related to UV exposure. Their molecular footprint often reflects the histologic tumor type, and familiarity with these changes will be increasingly necessary for diagnostic and therapeutic considerations.

Identifying Persons at Highest Risk of Melanoma Using Self-Assessed Risk Factors

OBJECTIVE: To develop a self-assessed melanoma risk score to identify high-risk persons for screening METHODS: We used data from a 1997 melanoma case-control study from Washington State, USA, where 386 cases with invasive cutaneous melanoma and 727 controls were interviewed by telephone. A logistic regression prediction model was developed on 75% of the data and validated in the remaining 25% by calculating the area under the receiver operating characteristic curve (AUC), a measure of predictive accuracy from 0.5-1 (higher scores indicating better prediction). A risk score was calculated for each individual, and sensitivities for various risk cutoffs were calculated. RESULTS: The final model included sex, age, hair color, density of freckles, number of severe sunburns in childhood and adolescence, number of raised moles on the arms, and history of non-melanoma skin cancer. The area under the receiver operating characteristic curve(AUC) was 0.70 (95% CI: 0.64, 0.77). The top 15% risk group included 50% of melanomas (sensitivity 50%). CONCLUSIONS: This self-assessed score could be used as part of a comprehensive melanoma screening and public education program to identify high-risk individuals in the general population. This study suggests it may be possible to capture a large proportion of melanomas by screening a small high-risk group. Further study is needed to determine the costs, feasibility, and risks of this approach.

Insights into melanoma: targeting the mTOR pathway for therapeutics

INTRODUCTION

Cutaneous melanoma represents < 5% of all skin cancers, but is responsible for the majority of skin cancer-related deaths. Ocular melanoma is the most common primary eye tumor in adults, and accounts for approximately 5% of all melanomas. Despite new diagnostic and therapeutic tools, the overall survival of patients treated for melanoma has not improved and most patients die of metastatic disease. Therefore, clarification of the molecular mechanisms underlying the etiopathogenesis of cutaneous and ocular melanomas may help determining the prognosis and tailoring therapy of patients harboring melanomas.

AREAS COVERED

In this review the authors aim to survey relevant research in the molecular mechanisms underlying melanomagenesis, and therapies under evaluation with emphasis in the mTOR pathway.

EXPERT OPINION

Despite an increasingly understanding of the genetics and biochemistry of melanoma, the mechanisms underlying their complex interactions are still poorly understood. Their clarification will lead to more successful therapeutic strategies and evidence-based management of patients with melanoma. More active drug combinations together with appropriate melanoma patient stratification based on molecular biomarkers will be essential for new advances in melanoma therapy.

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.

Site-dependent actinic skin damage as risk factor for melanoma in a central European population

Sun exposure is causal for melanoma but is subject to bias of recall so that it is difficult to dissect the role of particular patterns of sun exposure. In this hospital-based case-control study (n = 1991), we aimed to analyze pigmentation traits and signs of actinic damage at different anatomic locations as markers of melanoma risk in central European patients. Although all signs of actinic damage (freckling, wrinkling and solar lentigos) were significantly associated with melanoma risk in multivariate logistic regression models adjusting for age and sex, the strongest associations were observed for the dorsal parts of the body: adjusted odds ratios [OR] were 4.22 for wrinkling on the neck, 3.43 for solar lentigos and 3.37 for freckling on the back (all P < 0.001), respectively. These associations were independent of age, sex and pigmentation traits. Our results indicate that signs of actinic damage are predictors of melanoma risk, particularly on the back.

The melanomas: a synthesis of epidemiological, clinical, histopathological, genetic, and biological aspects, supporting distinct subtypes, causal pathways, and cells of origin

Converging lines of evidence from varied scientific disciplines suggest that cutaneous melanomas comprise biologically distinct subtypes that arise through multiple causal pathways. Understanding the respective relationships of each subtype with etiologic factors such as UV radiation and constitutional factors is the first necessary step toward developing refined prevention strategies for the specific forms of melanoma. Furthermore, classifying this disease precisely into biologically distinct subtypes is the key to developing mechanism-based treatments, as highlighted by recent discoveries. In this review, we outline the historical developments that underpin our understanding of melanoma heterogeneity, and we do this from the perspectives of clinical presentation, histopathology, epidemiology, molecular genetics, and developmental biology. We integrate the evidence from these separate trajectories to catalog the emerging major categories of melanomas and conclude with important unanswered questions relating to the development of melanoma and its cells of origin.

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.

Skin cancer risk factors among primary school children: investigations in Western Hungary

OBJECTIVE

To evaluate the factors associated with sunburns and with sun protection practice in Hungarian primary school children.

METHOD

We investigated children's (the median age: 8, range 5 to 12 years) and parents' assessment of sun sensitivity and sun protection characteristics in cities Gyor and Zalaegerszeg (Hungary) in 2004. This cross-sectional study was part of a programme intended to increase children's and parents' awareness of harmful effects of excessive sunbathing. Analyses were based on 1804 multiple choice questionnaires.

RESULTS

At multivariate analysis a significant association between sunburns and fairness of complexion, freckles, use of sunscreens and T-shirts, and higher school-class level was observed. Sunburn was inversely associated with hat-wearing. Parents were more likely to apply sunscreen to children with light eyes and to the younger ones, to protect fair skinned children with T-shirts; to protect males and children with fair skin and light eyes with hats.

CONCLUSION

Since environmental factors play an important role in the development of skin cancer, morbidity could be reduced by primary prevention. Sun protection habits should therefore be taught early in life, and parents' behaviour adapted. Phenotype is not only related to sunburns but it also appears to influence parents' sun safety behaviour.

IRF4 variants have age-specific effects on nevus count and predispose to melanoma

High melanocytic nevus count is a strong predictor of melanoma risk. A GWAS of nevus count in Australian adolescent twins identified an association of nevus count with the interferon regulatory factor 4 gene (IRF4 [p = 6 x 10(-9)]). There was a strong genotype-by-age interaction, which was replicated in independent UK samples of adolescents and adults. The rs12203592(*)T allele was associated with high nevus counts and high freckling scores in adolescents, but with low nevus counts and high freckling scores in adults. The rs12203592(*)T increased counts of flat (compound and junctional) nevi in Australian adolescent twins, but decreased counts of raised (intradermal) nevi. In combined analysis of melanoma case-control data from Australia, the UK, and Sweden, the rs12203592(*)C allele was associated with melanoma (odds ratio [OR] 1.15, p = 4 x 10(-3)), most significantly on the trunk (OR = 1.33, p = 2.5 x 10(-5)). The melanoma association was corroborated in a GWAS performed by the GenoMEL consortium for an adjacent SNP, rs872071 (rs872071(*)T: OR 1.14, p = 0.0035; excluding Australian, the UK, and Swedish samples typed at rs12203592: OR 1.08, p = 0.08).

Effect of hair color and sun sensitivity on nevus counts in white children in Colorado

BACKGROUND

It has been widely reported that individuals with a light phenotype (ie, light hair color, light base skin color, and propensity to burn) have more nevi and are at greater risk for developing skin cancer. No studies have systematically investigated how phenotypic traits may interact in relation to nevus development.

OBJECTIVE

We sought to systematically examine whether any combinations of phenotype are associated with a greater or lesser risk for nevus development in white children.

METHODS

In the summer of 2007, 654 children were examined to determine full body nevus counts, skin color by colorimetry, and hair and eye color by comparison with charts. Interviews of parents were conducted to capture sun sensitivity, sun exposure, and sun protection practices.

RESULTS

Among 9-year-old children with sun sensitivity rating type II (painful burn/light tan), those with light hair had lower nevus counts than did those with dark hair (P value for interaction = .03). This relationship was independent of eye color, presence of freckling, sex, usual daily sun exposure, sunburn in 2004 to 2007, sun protection index, and waterside vacation sun exposure. The difference in nevus counts was further determined to be specific to small nevi (<2 mm) and nevi in intermittently exposed body sites.

LIMITATIONS

Geographic and genetic differences in other study populations may produce different results.

CONCLUSION

The standard acceptance that dark phenotype is a marker for low melanoma risk and light phenotype a marker for high risk may need to be reevaluated. In non-Hispanic white children, dark-haired individuals who burn readily and then tan slightly are more prone to nevus development, and may therefore be a previously underrecognized high-risk group for melanoma.

Does MC1R genotype convey information about melanoma risk beyond risk phenotypes?

BACKGROUND

A study was carried out to describe associations of MC1R variants and melanoma in a US population and to investigate whether genetic risk is modified by pigmentation characteristics and sun exposure measures.

METHODS

Melanoma patients (n = 960) and controls (n = 396) self-reported phenotypic characteristics and sun exposure via structured questionnaire and underwent a skin examination. Logistic regression was used to estimate associations of high- and low-risk MC1R variants and melanoma, overall and within phenotypic and sun exposure strata. A meta-analysis of results from published studies was undertaken.

RESULTS

Carriage of 2 low-risk or any high-risk MC1R variants was associated with increased risk of melanoma (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.0-2.8; and OR, 2.2; 95% CI, 1.5-3.0, respectively). However, risk was stronger in or limited to individuals with protective phenotypes and limited sun exposure, such as those who tanned well after repeated sun exposure (OR, 2.4; 95% CI, 1.6-3.6), had dark hair (OR, 2.4; 95% CI, 1.5-3.6), or had dark eyes (OR, 3.2; 95% CI, 1.8-5.9). We noted this same pattern of increased melanoma risk among persons who did not freckle, tanned after exposure to first strong summer sun, reported little or average recreational or occupational sun exposure, or reported no sun burning events. Meta-analysis of published literature supported these findings.

CONCLUSIONS

These data indicate that MC1R genotypes provide information about melanoma risk in those individuals who would not be identified as high risk based on their phenotypes or exposures alone.

Melanoma risk factors, perceived threat and intentional tanning: an international online survey

Cutaneous melanoma continues to increase in incidence in many countries, and intentional tanning is a risk factor for melanoma. The aim of this study was to understand how melanoma risk factors, perceived threat and preferences for a suntan relate to intentional tanning. Self-report data were collected on behalf of GenoMEL (www.genomel.org) from the general population using an online survey. A total of 8178 individuals completed the survey, with 72.8% of respondents being from Europe, 12.1% from Australia, 7.1% from the US, 2.5% from Israel and 5.5% from other countries. Seven percent of respondents had previously been diagnosed with melanoma and 8% had at least one first-degree relative with a previous melanoma. Overall, 70% reported some degree of intentional tanning during the past year, and 38% of respondents previously diagnosed with melanoma had intentionally tanned. The total number of risk factors was positively correlated with perceived risk of melanoma [correlation coefficient (rho) = 0.27], and negatively correlated with intentional tanning (rho = -0.16). Preference for a dark suntan was the strongest predictor of intentional tanning [regression coefficient (beta) = 0.35, P<0.001], even in those with a previous melanoma (beta = 0.33, P<0.01). A substantial proportion of participants reported having phenotypic and behavioural risk factors for melanoma. The preference regarding suntans seemed more important in the participants' decision to intentionally tan than their perceived risk of developing melanoma, and this finding was consistent among respondents from different countries. The drive to sunbathe to tan is a key factor to be moderated if melanoma incidence is to be reduced.

Role of radiation therapy in cutaneous melanoma

Cutaneous melanoma is a disease that often has an aggressive and unpredictable course. It was historically thought to be a radioresistant neoplasm; however, substantial radiobiologic and clinical evidence has emerged to refute this notion. Improved local control has been demonstrated with the use of adjuvant radiation therapy delivered to the primary site or regional lymphatics in patients with high-risk clinical or pathologic features. Despite improved local control, high-risk cutaneous melanoma often spreads systemically, leading to poor survival. In the setting of systemic progression, radiation therapy can frequently palliate symptomatic sites of metastatic disease.

The melanocortin-1 receptor gene polymorphism and association with human skin cancer

The melanocortin-1 receptor (MC1R) is a key gene involved in the regulation of melanin synthesis and encodes a G-protein coupled receptor expressed on the surface of the melanocyte in the skin and hair follicles. MC1R activation after ultraviolet radiation exposure results in the production of the dark eumelanin pigment and the tanning process in humans, providing physical protection against DNA damage. The MC1R gene is highly polymorphic in Caucasian populations with a number of MC1R variant alleles associated with red hair, fair skin, freckling, poor tanning, and increased risk of melanoma and nonmelanoma skin cancer. Variant receptors have shown alterations in biochemical function, largely due to intracellular retention or impaired G-protein coupling, but retain some signaling ability. The association of MC1R variant alleles with skin cancer risk remains after correction for pigmentation phenotype, indicating regulation of nonpigmentary pathways. Notably, MC1R activation has been linked to DNA repair and may also contribute to the regulation of immune responses.

Vitamin D receptor gene polymorphisms, serum 25-hydroxyvitamin D levels, and melanoma: UK case-control comparisons and a meta-analysis of published VDR data

We have carried out melanoma case-control comparisons for six vitamin D receptor (VDR) gene single nucleotide polymorphisms (SNPs) and serum 25-hydroxyvitamin D(3) levels in order to investigate the role of vitamin D in melanoma susceptibility. There was no significant evidence of an association between any VDR SNP and risk in 1028 population-ascertained cases and 402 controls from Leeds, UK. In a second Leeds case-control study (299 cases and 560 controls) the FokI T allele was associated with increased melanoma risk (odds ratio (OR) 1.42, 95% confidence interval (CI) 1.06-1.91, p=0.02). In a meta-analysis in conjunction with published data from other smaller data sets (total 3769 cases and 3636 controls), the FokI T allele was associated with increased melanoma risk (OR 1.19, 95% CI 1.05-1.35), and the BsmI A allele was associated with a reduced risk (OR 0.81, 95% CI 0.72-0.92), in each instance under a parsimonious dominant model. In the first Leeds case-control comparison cases were more likely to have a higher body mass index (BMI) than controls (p=0.007 for linear trend). There was no evidence of a case-control difference in serum 25-hydroxyvitamin D(3) levels. In 1043 incident cases from the first Leeds case-control study, a single estimation of serum 25-hydroxyvitamin D(3) level taken at recruitment was inversely correlated with Breslow thickness (p=0.03 for linear trend). These data provide evidence to support the view that vitamin D and VDR may have a small but potentially important role in melanoma susceptibility, and putatively a greater role in disease progression.