Survival analysis and sentinel lymph node status in thin cutaneous melanoma: A multicenter observational study

Mitotic rate is no longer considered a staging criterion for thin melanoma in the 8th edition of the American Joint Committee on Cancer Staging Manual. The aim of this observational study was to identify prognostic factors for thin melanoma and predictors and prognostic significance of sentinel lymph node (SLN) involvement in a large multicenter cohort of patients with melanoma from nine tertiary care hospitals. A total of 4249 consecutive patients with thin melanoma diagnosed from January 1, 1998 to December 31, 2016 were included. The main outcomes were disease-free interval and melanoma-specific survival for the overall population and predictors of SLN metastasis (n = 1083). Associations between survival and SLN status and different clinical and pathologic variables (sex, age, tumor location, mitosis, ulceration, regression, lymphovascular invasion, histologic subtype, Clark level, and Breslow thickness) were analyzed by Cox proportional hazards regression and logistic regression. SLN status was the most important prognostic factor for melanoma-specific survival (hazard ratio, 13.8; 95% CI, 6.1-31.2; P < 0.001), followed by sex, ulceration, and Clark level for patients who underwent SLNB. A mitotic rate of >2 mitoses/mm2 was the only factor associated with a positive SLN biopsy (odds ratio, 2.9; 95% CI, 1.22-7; P = 0.01. SLN status is the most important prognostic factor in thin melanoma. A high mitotic rate is associated with metastatic SLN involvement. SLN biopsy should be discussed and recommended in patients with thin melanoma and a high mitotic rate.

No association between smoking and sentinel lymph node metastasis and survival in cutaneous melanoma

BACKGROUND

There is little evidence that smoking is associated with metastasis in patients with cutaneous melanoma.

OBJECTIVE

Using a propensity score matching analysis, we assessed whether smoking was associated with a higher rate of sentinel lymph node (SLN) metastasis and worse survival in these patients.

METHODS

Retrospective cohort study at a referral hospital for melanoma. We studied 762 patients with known smoking status from the melanoma database of the Instituto Valenciano de Oncología who underwent SLN biopsy between 1 January 2000 and 31 December 2016. The patients were matched by smoking status. The matching procedure was implemented using three logistic regression models featuring never vs. former smokers, never vs. current smokers and former vs. current smokers. The study outcomes were disease-free survival (DFS), melanoma-specific survival (MSS), overall survival (OS) and SLN status.

RESULTS

The following groups were formed based on the propensity matching scores: 114 pairs of smokers vs. never smokers, 113 pairs of smokers vs. former smokers and 174 pairs of never smokers vs. former smokers. Smoking status was not associated with SLN metastasis or with DFS, MSS or OS in any of the three groups.

CONCLUSION

Smoking does not influence SLN metastasis or survival in patients with cutaneous melanoma.

Abstract 2022: Chronic UV damage of the stroma improves melanoma survival

Introduction Skin that is exposed to chronic UV presents a distinct pattern of structural degradation compared to age-matched, sun-protected skin. The morphological change underpinning chronic UV cutaneous damage is collagen degradation of the dermis. Molecularly, UV-aged skin accumulates primarily UV-driven mutations, in contrast to UV-protected skin where mutations are rare. The enrichment of mutations in non-neoplastic, aged cells is a defining feature of skin ageing. Melanoma increases with age, and most patients who die are older than 55. Age is the most important independent marker of adverse outcome together with tumor thickness. Old patients commonly present melanoma over chronic UV-damaged skin with a high number of mutations, and some studies suggest these may be linked to better outcome. Here we explore the relationship between tumor mutation burden, stromal DNA damage and outcome of elderly primary melanoma patients.

Results We examined the types of mutations contributing to the somatic mutation load in melanoma. We inferred the signature linked to accumulated UV DNA damage (signature 7 from COSMIC), as well as the intrinsic, proliferation and age-related signature (signature 1). Logistic regression models of signature 1 and 7 demonstrate both correlate with age, and elderly patients are at higher risk of death in this cohort. These data are in contrast to studies suggesting melanomas arising at sites of chronic sun exposure (CSE) have an improved survival, and studies showing higher mutation rates in melanoma are linked to better outcome. To test this, we generated isogenic melanoma cell lines with high versus low UV-mutation burden, and found CSE melanoma cells were more proliferative, invasive and migratory. We next investigated if a higher rate of UV damage to dermal fibroblasts affects outcome by generating isogenic CSE and noCSE dermal fibroblast lines and found melanoma cells exposed to noCSE fibroblasts were more invasive than melanoma cells exposed to CSE fibroblasts. We validated this in human dermal fibroblasts. Dermal fibroblasts from protected sites presented few mutations and promoted melanoma invasion, whereas fibroblasts from chronic UV skin had more mutations and did not drive melanoma invasion. Furthermore, CSE fibroblasts with many mutations present a distinct expression and metabolic profile linked to the sunburn response genes that blocks melanoma invasion. We validated our findings in 490 specimens of elderly primary cutaneous melanoma patients. Multivariate analysis shows the presence of degraded collagen, a surrogate marker of UV damage, is an independent marker of better outcome in the elderly population.

Discussion Our study shows UV-driven damage in aged dermal fibroblasts protects from primary melanoma invasion and humans with extensive dermal UV damage present an improved outcome. Our finding that excessive UV can improve outcome of patients with melanoma is a paradigm shift.

Citation Format: Eduardo Nagore, Katharina Roeck, Timothy Budden, Stephen P. Smith, Sarah Craig, Jean Krutmann, Martin Lotz, Simon Furney, Amaya Viros. Chronic UV damage of the stroma improves melanoma survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2022.

Abstract 3994: Genomic characterization of melanoma in the elderly reveals molecular drivers of progression and prognosis associated with immunotherapy response

Melanoma incidence and mortality particularly affects elderly patients. 85% of melanoma deaths occur in patients older than 60, and age is a powerful independent predictor of outcome. The genomic characteristics driving melanoma in the aged population have not been previously investigated.

We have undertaken a comprehensive genomic analysis of age-specific molecular characteristics in metastatic cutaneous melanoma and discovered a core set of 4 driver genes that when mutated in older patients is a powerful predictor of poor outcome. We validate these findings in international independent primary melanoma replication cohorts. This signature stratifies patient prognosis more accurately than the current staging guidelines from early to late stages, making it relevant to immediate clinical practice.

Checkpoint inhibitors are showing promising results in the adjuvant setting to treat early stage melanoma patients, and the cost burden to health care will limit access to these drugs. Importantly, elderly patients benefit from immune checkpoint inhibitor therapies, and there are currently no accepted predictors of response used to prioritize patients for these costly therapies in the adjuvant or advanced disease stages. Previous studies have shown a higher mutation burden and neo-antigen load are indicators of response.

Critically, we show elderly melanoma patients are the population subset most likely to present with a higher mutation burden, and our signature strongly correlates with melanomas of higher mutation burden and neo-antigen load. We validate these findings across multiple primary and metastatic melanoma cohorts. Finally, stratifying old patients by our 4-gene outcome signature is also associated with immunotherapy response in the metastatic stage. Our study demonstrates that stratifying patients by age will allow improved discrimination of prognosis and association with response to treatment.

Current selection of patients is based on AJCC stage alone, which means more patients have to be enrolled and more time is required to discriminate the effect of novel adjuvant immunotherapy strategies. Our work, validated across multiple cohorts, directly proposes enrolling patients with high genetic risk of poor outcome and improved rate of immunotherapy response using a simple 4-gene DNA signature that can be easily translated into clinical practice.

Citation Format: Stephen P. Smith, Caroline Gaudy-Marqueste, Rajive Kumar, Richard Marais, Eduardo Nagore, Amaya Viros. Genomic characterization of melanoma in the elderly reveals molecular drivers of progression and prognosis associated with immunotherapy response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3994.

Histologic Features Associated With an Invasive Component in Lentigo Maligna Lesions

Importance

Lentigo maligna (LM) presents an invasive component in up to 20% of biopsied cases, but to date the histologic features useful in detecting this invasive component have not been described. Some histologic characteristics are hypothesized to contribute to the progression of LM invasion.

Objective

To identify the histologic characteristics associated with lentigo maligna melanoma (LMM) in patients with LM diagnosed by a partial diagnostic biopsy.

Design, Setting, and Participants

A retrospective cross-sectional study of patients treated between January 1, 2000, and December 31, 2017, was conducted in a referral oncology center in València, Spain. Data and specimens of patients (n = 96) with a diagnosis of primary cutaneous melanoma in the form of either LM or LMM who had undergone surgical treatment, a complete histologic examination of the whole tumor, and an initial diagnostic partial biopsy of LM were included in the study. Histologic assessment was blinded to the presence of an invasive component.

Interventions

All biopsy specimens were evaluated for the presence of certain histologic characteristics.

Main Outcomes and Measures

Comparisons between invasive samples and samples without an invasive component were performed. The differences in the distribution of variables between the groups were assessed using the χ2 and Fisher exact tests, and the degree of association of the relevant variables was quantified by logistic regression models. A classification and regression tree analysis was performed to rank the variables by importance.

Results

In total, 96 patients had sufficient histologic material that could be evaluated. The patients were predominantly male (56 [58.3%]) and had a mean (SD) age at diagnosis of 72 (12) years. Of these patients, 63 (65.6%) had an LM diagnosis and 33 (34.4%) had an LMM diagnosis (an invasive component). The histologic variables associated with the presence of an invasive component were melanocytes forming rows (odds ratio [OR], 11.5; 95% CI, 1.4-94.1; P = .02), subepidermal clefts (OR, 2.8; 95% CI, 1.0-7.9; P = .049), nests (OR, 3.0; 95% CI, 1.1-8.6; P = .04), and a lesser degree of solar elastosis (OR, 0.4; 95% CI, 0.1-1.1; P = .07). A classification and regression tree analysis of the relevant histologic features was able to accurately identify lentigo maligna with an invasive component (LMM) in more than 60% of patients.

Conclusions and Relevance

These findings may be useful in classifying early LM specimens at higher risk of invasion, which may eventually be relevant in identifying the most appropriate management for LM.

Prevalence and determinants of sunbed use in thirty European countries: data from the Euromelanoma skin cancer prevention campaign

BACKGROUND

Although considered as a first-group carcinogen, indoor tanning is a common practice in Europe. Euromelanoma is a pan-European skin cancer prevention campaign.

OBJECTIVES

To compare several European countries in terms of the prevalence and determinants of sunbed use.

METHODS

Participants in the Euromelanoma campaigns filled in questionnaires containing demographics and risk factors, including type/duration of sunbed use. Multivariate analyses adjusted for age, gender, education, skin type and year of survey were employed to assess factors independently associated with sunbed use in each country.

RESULTS

In total, 227 888 individuals (67.4% females, median age 44, 63.4% highly educated, 71.9% skin types III-VI) from 30 countries participated. Overall, the prevalence of sunbed ever use was 10.6% (≤19-year-olds: 5.9%; 20 to 35-year-olds: 17.0%; >35-year-olds: 8.3%). Females displayed a higher prevalence than males in all countries. Balkan countries displayed the highest female/male ratios (≥4). Sunbed use was significantly more prevalent among skin type III-VI (14/30 countries) and highly educated participants (11/30 countries). Significant correlations were found between sunbed use prevalence and countries' latitude (P < 0.001) and sunshine (P = 0.002); Italy and Spain represented exceptions towards excessive exposure. Very different prevalence rates were found for Spain (19.3%) and Portugal (2.0%). Scandinavian countries ranked highest in sunbed use among ≤19-year-olds, Baltic countries among 20 to 35-year-olds.

CONCLUSIONS

Sunbed use prevalence was higher in northern, sun-deprived countries, with the exception of Italy and Spain. The main determinants of sunbed use were age (young adults) and gender (females), whereas education and skin type had a less relevant effect. Geographic particularities were found in four regions: Iberian (prevalence ten times higher in Spain than Portugal), Balkan (prevalence disproportionately higher among women), Baltic (highest prevalence among young adults) and Scandinavian (highest prevalence among adolescents). These data have public health relevance for future interventions aimed at reducing sunbed use in Europe.

Association of sunbed use with skin cancer risk factors in Europe: an investigation within the Euromelanoma skin cancer prevention campaign

INTRODUCTION

Sunbed use has been significantly associated with increased risk of melanoma and non-melanoma skin cancer (NMSC), but its relationship with melanoma's risk factors such as high nevus count, atypical nevi and lentigines is poorly studied. Euromelanoma is a skin cancer prevention campaign conducted all over Europe. It offers a once-a-year screening during which participants' data, including sunbed use and phenotype, are collected via questionnaires.

OBJECTIVES

To investigate the association of sunbed use with nevus count, atypical nevi, lentigines and suspicion of skin cancer.

METHODS

To ensure reliability of the data, we defined inclusion and exclusion criteria for countries' eligibility for the risk analysis. Multivariate logistic regression models (including age, gender, education, skin type, family history of melanoma, personal history of skin cancer, any sun exposure and any sunscreen use) were used to calculate summary odds ratios (SORs) of each clinical endpoint for ever sunbed use.

RESULTS

Overall, 227 888 individuals from 30 countries completed the Euromelanoma questionnaire. After the data quality check, 16 countries were eligible for the multivariate analysis, for a total of 145 980 participants (64.8% females; median age 43 years; 62.3% highly educated; 28.5% skin type I-II; 11.0% ever sunbed use). Ever sunbed use was independently associated with nevus count >50 [SOR = 1.05 (1.01-1.10)], atypical nevi [SOR = 1.04 (1.00-1.09)], lentigines [SOR = 1.16 (1.04-1.29)] and suspicion of melanoma [SOR = 1.13 (1.00-1.27)]. Conversely, no significant association was found between ever sunbed use and suspicion of NMSC [SOR = 1.00 (0.91-1.10)].

CONCLUSIONS

Indoor tanning is significantly associated with well-recognized risk factors for melanoma (including high nevus count, presence of atypical nevi and lentigines) as well as suspicion of melanoma within the Euromelanoma screenees. In order to reduce the prevalence of melanoma risk factors, avoidance/discontinuation of sunbed use should always be encouraged, especially but not exclusively for individuals with high-risk phenotypes.

MC1R variants in childhood and adolescent melanoma: a retrospective pooled analysis of a multicentre cohort

BACKGROUND

Germline variants in the melanocortin 1 receptor gene (MC1R) might increase the risk of childhood and adolescent melanoma, but a clear conclusion is challenging because of the low number of studies and cases. We assessed the association of MC1R variants with childhood and adolescent melanoma in a large study comparing the prevalence of MC1R variants in child or adolescent patients with melanoma to that in adult patients with melanoma and in healthy adult controls.

METHODS

In this retrospective pooled analysis, we used the M-SKIP Project, the Italian Melanoma Intergroup, and other European groups (with participants from Australia, Canada, France, Greece, Italy, the Netherlands, Serbia, Spain, Sweden, Turkey, and the USA) to assemble an international multicentre cohort. We gathered phenotypic and genetic data from children or adolescents diagnosed with sporadic single-primary cutaneous melanoma at age 20 years or younger, adult patients with sporadic single-primary cutaneous melanoma diagnosed at age 35 years or older, and healthy adult individuals as controls. We calculated odds ratios (ORs) for childhood and adolescent melanoma associated with MC1R variants by multivariable logistic regression. Subgroup analysis was done for children aged 18 or younger and 14 years or younger.

FINDINGS

We analysed data from 233 young patients, 932 adult patients, and 932 healthy adult controls. Children and adolescents had higher odds of carrying MC1R r variants than did adult patients (OR 1·54, 95% CI 1·02-2·33), including when analysis was restricted to patients aged 18 years or younger (1·80, 1·06-3·07). All investigated variants, except Arg160Trp, tended, to varying degrees, to have higher frequencies in young patients than in adult patients, with significantly higher frequencies found for Val60Leu (OR 1·60, 95% CI 1·05-2·44; p=0·04) and Asp294His (2·15, 1·05-4·40; p=0·04). Compared with those of healthy controls, young patients with melanoma had significantly higher frequencies of any MC1R variants.

INTERPRETATION

Our pooled analysis of MC1R genetic data of young patients with melanoma showed that MC1R r variants were more prevalent in childhood and adolescent melanoma than in adult melanoma, especially in patients aged 18 years or younger. Our findings support the role of MC1R in childhood and adolescent melanoma susceptibility, with a potential clinical relevance for developing early melanoma detection and preventive strategies.

FUNDING

SPD-Pilot/Project-Award-2015; AIRC-MFAG-11831.

Soluble PD-L1 is a potential biomarker of cutaneous melanoma aggressiveness and metastasis in obstructive sleep apnoea patients

Obstructive sleep apnoea (OSA) upregulates the programmed cell death-1 receptor and its ligand (PD-L1) pathway, potentially compromising immunosurveillance. We compared circulating levels of soluble PD-L1 (sPD-L1) in patients with cutaneous melanoma according to the presence and severity of OSA, and evaluated relationships with tumour aggressiveness and invasiveness.In a multicentre observational study, 360 patients with cutaneous melanoma underwent sleep studies, and serum sPD-L1 levels were assayed using ELISA. Cutaneous melanoma aggressiveness indices included mitotic rate, Breslow index, tumour ulceration, Clark level and tumour stage, and sentinel lymph node (SLN) metastasis was recorded as a marker of invasiveness.sPD-L1 levels were higher in severe OSA compared to mild OSA or non-OSA patients. In OSA patients, sPD-L1 levels correlated with Breslow index and were higher in patients with tumour ulceration, advanced primary tumour stages or with locoregional disease. The incorporation of sPD-L1 to the classic risk factors to SLN metastasis led to net improvements in the classification of 27.3%.Thus, sPD-L1 levels are increased in melanoma patients with severe OSA, and, in addition, might serve as a potential biomarker of cutaneous melanoma aggressiveness and invasiveness in this group of subjects.

Prevalence of pathogenic/likely pathogenic variants in the 24 cancer genes of the ACMG Secondary Findings v2.0 list in a large cancer cohort and ethnicity-matched controls

Background

Prior research has established that the prevalence of pathogenic/likely pathogenic (P/LP) variants across all of the American College of Medical Genetics (ACMG) Secondary Findings (SF) genes is approximately 0.8–5%. We investigated the prevalence of P/LP variants in the 24 ACMG SF v2.0 cancer genes in a family-based cancer research cohort (n = 1173) and in cancer-free ethnicity-matched controls (n = 982).

Methods

We used InterVar to classify variants and subsequently conducted a manual review to further examine variants of unknown significance (VUS).

Results

In the 24 genes on the ACMG SF v2.0 list associated with a cancer phenotype, we observed 8 P/LP unique variants (8 individuals; 0.8%) in controls and 11 P/LP unique variants (14 individuals; 1.2%) in cases, a non-significant difference. We reviewed 115 VUS. The median estimated per-variant review time required was 30 min; the first variant within a gene took significantly (p = 0.0009) longer to review (median = 60 min) compared with subsequent variants (median = 30 min). The concordance rate was 83.3% for the variants examined by two reviewers.

Conclusion

The 115 VUS required database and literature review, a time- and labor-intensive process hampered by the difficulty in interpreting conflicting P/LP determinations. By rigorously investigating the 24 ACMG SF v2.0 cancer genes, our work establishes a benchmark P/LP variant prevalence rate in a familial cancer cohort and controls.

Electronic supplementary material

The online version of this article (10.1186/s13073-018-0607-5) contains supplementary material, which is available to authorized users.

Author Correction: Telomere length and survival in primary cutaneous melanoma patients

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Correction: Cutaneous melanoma primary site is linked to nevus density

[This corrects the article DOI: 10.18632/oncotarget.22016.].

Combining common genetic variants and non-genetic risk factors to predict risk of cutaneous melanoma

Melanoma heritability is among the highest for cancer and single nucleotide polymorphisms (SNPs) contribute to it. To date, only SNPs that reached statistical significance in genome-wide association studies or few candidate SNPs have been included in melanoma risk prediction models. We compared four approaches for building polygenic risk scores (PRS) using 12 874 melanoma cases and 23 203 controls from Melanoma Meta-Analysis Consortium as a training set, and newly genotyped 3102 cases and 2301 controls from the MelaNostrum consortium for validation. We estimated adjusted odds ratios (ORs) for melanoma risk using traditional melanoma risk factors and the PRS with the largest area under the receiver operator characteristics curve (AUC). We estimated absolute risks combining the PRS and other risk factors, with age- and sex-specific melanoma incidence and competing mortality rates from Italy as an example. The best PRS, including 204 SNPs (AUC = 64.4%; 95% confidence interval (CI) = 63-65.8%), developed using winner's curse estimate corrections, had a per-quintile OR = 1.35 (95% CI = 1.30-1.41), corresponding to a 3.33-fold increase comparing the 5th to the 1st PRS quintile. The AUC improvement by adding the PRS was up to 7%, depending on adjusted factors and country. The 20-year absolute risk estimates based on the PRS, nevus count and pigmentation characteristics for a 60-year-old Italian man ranged from 0.5 to 11.8% (relative risk  = 26.34), indicating good separation.

Sleep-Disordered Breathing Is Independently Associated With Increased Aggressiveness of Cutaneous Melanoma: A Multicenter Observational Study in 443 Patients

BACKGROUND

Sleep-disordered breathing (SDB) has been associated with a greater incidence and mortality of cancer, although such findings are inconsistent. However, no large studies are currently available to investigate this association in patients with a specific type of cancer. This study seeks to assess potential relationships between SDB severity and aggressiveness markers of cutaneous melanoma.

METHODS

Four hundred and forty-three patients with a diagnosis of melanoma underwent a sleep study within 6 months of diagnosis. General demographics were collected, along with melanoma characteristics and polygraphic parameters consisting of the apnea-hypopnea index (AHI) and indices of both continuous and intermittent night-time oxyhemoglobin desaturation (DI4%). An exploration of independent relationships between SDB and various objective melanoma aggressiveness markers (Breslow index, presence of ulceration, presence of regression, mitotic index, stage of severity, damage to the sentinel lymph, and spreading of the melanoma) was performed.

RESULTS

Patients in the upper tertiles of AHI or DI4% were 1.94 (95% CI, 1.14-3.32; P = .022) and 1.93 (95% CI, 1.14-3.26; P = .013) times more likely, respectively, to present with aggressive melanoma (Breslow index > 1 mm) than those in the lowest tertiles of these sleep attributes after adjustment for age, sex, tumor location, and BMI. This association was particularly prominent among patients < 56 years of age with Breslow index > 2 mm. The presence of the additional markers of aggressiveness was also associated with higher AHI and DI4% values.

CONCLUSIONS

The severity of SDB was independently associated with greater aggressiveness of cutaneous melanoma, particularly among younger patients.

TERT promoter mutation subtypes and survival in stage I and II melanoma patients

Mutations within the promoter of gene encoding telomerase reverse transcriptase subunit are frequent in many cancers including melanoma. Previously, the TERT promoter mutations were shown to associate with markers of poor outcome and reduced survival in patients with primary melanoma. In this study, we investigated the impact of the subtypes of TERT mutations on disease-free and melanoma-specific survival in 287 patients with stage I/II nonacral melanoma. Our results showed that of the three TERT promoter mutation subtypes, in multivariate models, the -138/-139 CC > TT tandem mutation associated with worst disease-free and melanoma-specific survival. In particular, in combination with BRAF/NRAS mutations, the -138/-139 CC > TT TERT promoter mutation associated with statistically significant poor disease-free and melanoma-specific survival with hazard ratios of 6.04 (95% CI 2.03-17.94, p = 0.001) and 12.59 (95% CI 2.18-72.70, p = 0.005), respectively. In contrast to the survival data, luciferase assays showed that the highest activity was observed in experiments with a promoter construct with -124 C > T mutation followed by the -138/-139 CC > TT and -146 C > T mutations, which showed similar activity. Based on previous reports, we speculate that the tandem mutation probably leads to greater genomic instability than the common TERT promoter mutations, hence the association with worst survival. However, the results from the study are only preliminary with limited patient data, therefore, require a cautious interpretation. The observations in this study, if confirmed, could have implications for melanoma patients treated with MAP-kinase inhibitors.

MelaNostrum: a consensus questionnaire of standardized epidemiologic and clinical variables for melanoma risk assessment by the melanostrum consortium

BACKGROUND

Many melanoma observational studies have been carried out across different countries and geographic areas using heterogeneous assessments of epidemiologic risk factors and clinical variables.

AIM

To develop a consensus questionnaire to standardize epidemiologic and clinical data collection for melanoma risk assessment.

METHODS

We used a stepwise strategy that included: compilation of variables from case-control datasets collected at various centres of the MelaNostrum Consortium; integration of variables from published case-control studies; consensus discussion of the collected items by MelaNostrum members; revision by independent experts; addition of online tools and image-based charts; questionnaire testing across centres and generation of a final draft.

RESULTS

We developed a core consensus questionnaire (MelanoQ) that includes four separate sections: A. general and demographic data; B. phenotypic and ultraviolet radiation exposure risk factors and lifestyle habits; C. clinical examination, medical and family history; and D. diagnostic data on melanoma (cases only). Accompanying online tools, informative tables, and image-based charts aid standardization. Different subsections of the questionnaire are designed for self-administration, patient interviews performed by a physician or study nurse, and data collection from medical records.

CONCLUSIONS

The MelanoQ questionnaire is a useful tool for the collection and standardization of epidemiologic and clinical data across different studies, centres, cultures and languages. This will expedite ongoing efforts to compile high-quality data for pooled analyses or meta-analyses and offer a solid base for the design of clinical, epidemiologic and translational studies on melanoma.

Telomere length, telomerase reverse transcriptase promoter mutations, and melanoma risk

Telomere repeats at chromosomal ends, critical for genomic integrity, undergo age-dependent attrition and telomere length has been associated with different disorders including cancers. In this study, based on 1469 patients and 1158 healthy controls, we show a statistically significant (P = 6 × 10^-10 ) association between increased telomere length and melanoma risk. Mendelian randomization, using 5 telomere length-associated polymorphisms, ruled out confounding factors or reverse causality and showed association between increased telomere length and melanoma risk with odds ratio of 2.66 (95% confidence interval: 2.07-3.25). Age-dependent telomere attrition was faster in melanoma cases than controls (P = .01). The carriers of a highly penetrant germline -57A>C TERT promoter mutation, in a previously reported melanoma family, had longer telomeres than the noncarriers. The mutation causes increased TERT and telomerase levels through creation of a binding motif for E-twenty six (ETS) transcription factors and the carriers develop melanoma with an early age of onset and rapid progression to metastasis. In analogy, we hypothesize that increased telomere length in melanoma patients reflects stochastic increased telomerase levels due to common genetic variation. Paradoxically, we observed shorter telomeres (P = 1 × 10^-5 ) in primary tumors from unrelated melanoma patients with (121) than without (170) somatic TERT promoter mutations that similar to the germline mutation, also create binding motifs for ETS transcription factors. However, the age-dependent telomere attrition was faster in tumors with the TERT promoter mutations than in those without such mutations. Besides a robust association between increased telomere length and risk, our data show a perturbed telomere homeostasis in melanoma.

Telomere length and survival in primary cutaneous melanoma patients

Telomere repeats at chromosomal ends, critical to genomic integrity, undergo age-dependent attrition. Telomere length, a polygenic trait, has been associated with risk of several disorders including cancers. In contrast to association of long telomeres with increased risk of several cancers, including melanoma, emerging reports suggest that short telomeres predict poor survival in patients with different cancers. In this study based on 1019 stage I and II cutaneous melanoma patients, we show an association between the patients with short telomeres and poor melanoma-specific survival (HR 2.05, 95% CI 1.33-3.16) compared to patients with long telomeres. Due to inverse correlation between age and telomere length (r -0.19, P < 0.0001), we stratified the patients into quantiles based on age at diagnosis and also carried out age-matched analysis. The effect of short telomeres on survival was determined by using multivariate Cox regression that included composite genetic risk score computed from genotyping of the patients for telomere-length associated polymorphisms. The effect of decreased telomere length on poor melanoma-specific survival was particularly strong in patients within the age quantile below 30 years (HR 3.82, 95% CI 1.10-13.30) and between 30-40 years (HR 2.69, 95% CI 1.03-7.03). Our study shows that in contrast to increased melanoma risk associated with increased telomere length, decreased telomere length predicts poor survival in melanoma subgroups.

Abstract 228: Association analysis across different populations identifies 26 new cutaneous melanoma risk loci

Heritability of cutaneous melanoma is among the highest across cancer types and is mostly determined by common, noncoding genetic variants. Previous genome-wide association studies (GWAS), mostly including subjects from Australia and Northern European countries, had identified twenty genetic loci associated with melanoma risk. To characterize the genetic landscape of cutaneous melanoma across different populations, we conducted a new association study in Southern European countries including 6,043 melanoma cases and 10,383 controls from the MelaNostrum Consortium. Moreover, we largely expanded the analyses of melanoma cases and controls from other populations, for a total of 27,450 histologically confirmed melanoma cases and 49,888 controls from Northern Europe, Southern Europe, USA and Australia. Imputation was done using the Haplotype Reference Consortium as a reference panel. We assessed the association between cutaneous melanoma risk and single-nucleotide polymorphisms (SNPs) adjusting for country and ancestry-informative principal components. We identified 26 new genetic loci associated with melanoma risk achieving genome-wide significance. The pigmentation pathway, with TYRP1 and MITF, and the telomere-related pathway with RTEL1, TERC, and POT1 among the candidate genes, continued to show an important role for melanoma susceptibility. Additional candidate pathways emerged, including signaling (with GPRC5A and DOCK8), cell-cell junction (with CDH1), immune-related functions (with DCST2, involved in antigen processing), transcriptional regulation (with FOXD3, which represses MITF expression), or tumor-suppressor genes (TP53). Adding genotype data from 6,130 self-reported melanoma cases in a sensitivity analysis identified eight additional novel genetic loci involved in the HLA region, signaling transduction and transcription factor functions. A combined analysis of the melanoma GWAS with the GWAS of pigmentation characteristics from the UK Biobank including 500,000 UK persons, and with a GWAS of nevus density including over 52,000 persons, revealed substantial overlap across phenotypes. Although the effect size of the SNPs on melanoma risk was consistent across populations, substantial differences in minor allele frequency (MAF) were observed in pigmentation-related genes between Northern and Southern European populations; for example, MC1R, SLC45A2, and ASIP SNP MAF was 8.2, 3.1 and 14.2 in Northern and 2.6, 8.8, and 5.5 in Southern European subjects, respectively. Additional analyses based on melanoma histologic subtypes and body site distribution are ongoing. These results provide further insight into genetic susceptibility to cutaneous melanoma and provide the opportunity for genetic risk scores in risk-prediction models for early detection and targeted prevention of the disease.

Citation Format: Cristina Pellegrini, Matthew Law, Mark Iles, Mitch Machiela, Alex Stratigos, Tongwu Zhang, Kevin Brown, Julia Newton-Bishop, Nick Hayward, Nick Martin, Alisa Goldstein, Rose Yang, Stephen Chanock, Florence Demenais, Susana Puig, Eduardo Nagore, Jianxin Shi, Tim Bishop, Stuart McGregor, Maria Teresa Landi, GenoMEL Consortium, MelaNostrum Consortium. Association analysis across different populations identifies 26 new cutaneous melanoma risk loci [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 228.

Abstract 1407: Telomere length and melanoma survival

Telomeres at chromosomal ends are comprised of multiple short repeat sequences. In humans TTAGGG repeats account for 10-15 kb of double-stranded telomeres that end in single stranded G-rich tails of about 150-200 nucleotides. Telomeres in somatic cells undergo gradual shortening due to inherent limitations of DNA replication and limited levels of specialized enzyme telomerase. We previously reported an association between increased telomere length and risk of melanoma. In this study based on 1019 stage I and II cutaneous melanoma patients, we determined the effect of telomere length on patient survival. The telomere length was measured in DNA from peripheral blood cells using monochrome multiplex quantitative real-time PCR where telomere repeat copy number (T) was compared to a single-copy gene, albumin (S) and results presented as relative telomere length based on T/S ratio. A univariate Cox regression showed increased patient survival with increased telomere length (HR 0.65, 95% CI 0.42-1.00, P 0.05). With every decrease in 1 unit of telomere length the estimated odds of survival decreased by an approximate factor of 1.54 (95%CI 1.00-2.38). A model based on median distribution showed short rather than long telomere associated with poor survival with hazard ratio (HR) of 2.05 (95% confidence interval (CI) 1.33-3.16; log rank P 0.001); the model after adjustment with confounding factors including age at diagnosis showed a HR of 1.50 (95%CI 0.96-2.34). Stratification of patients based on median age showed statistically significant effect of decreased telomere length on poor survival in patients below the median age (HR 2.27 95%CI 1.09-4.27) but not in patients above the median age (HR 1.42 95%CI 0.82-2.46). Distribution of the patients into quantiles based on age showed the largest effect of decreased telomere length in patients younger than 30 years (HR 3.90 95%CI 1.28-11.93); the effect decreased with increasing age. Three single nucleotide polymorphisms, rs131178082, rs7726159 and rs6060627, previously shown to be associated with telomere length, were used to construct a weighted genetic score and paradoxically, the patients carrying the alleles associated with increased telomere length showed poor survival with shorter telomeres (HR 2.94 95%CI 1.54-5.62). Multivariate analysis that included, age, sex, outdoor life style, presence of actinic keratosis, number of nevi, tumor location, tumor stage, Breslow thickness and tumor ulceration showed a statistically significant association between composite genetic score and poor survival (HR 2.68 95%CI 1.24-5.80). Thus, the results from the study show that in contrast to association between melanoma risk and increased telomere length, the decreased telomere length associates with poor patient survival. The adverse effect on survival due to decreased telomere length was more pronounced in young rather than old patients and on the patients carrying genotypes for longer telomeres.

Citation Format: Sivaramakrishna Rachakonda, Nalini Srinivas, Zaida Garcia-Casado, Celia Requena, Eduardo Nagore, Rajiv Kumar. Telomere length and melanoma survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1407.

Dysplastic vs. Common Naevus-associated vs. De novo Melanomas: An Observational Retrospective Study of 1,021 Patients

The aim of this case-case study was to determine the differences between dysplastic and common naevus-associated melanomas (NAM) and de novo melanomas. A total of 1,021 prospectively collected patients with invasive cutaneous melanoma from an oncology referral centre were included in the study. Of these, 75.51% had de novo melanomas, 12.93% dysplastic NAM, and 11.56% common NAM. Dysplastic NAM, compared with de novo melanomas, were associated with intermittently photo-exposed sites, atypical melanocytic naevi, decreased tumour thickness, and presence of MC1R non-synonymous variants. Common NAM were more frequent on the trunk and of superficial spreading type. Comparison of dysplastic with common NAM showed significant difference only with regard to mitoses. Both subtypes of NAM shared less aggressive traits than de novo melanomas, albeit with no significant differences in survival after multivariate adjustment. In conclusion, NAM present with less aggressive traits, mostly due to a greater awareness among patients of changing moles than due to their intrinsic biological characteristics.