Characterization of Potential Melanoma Predisposition Genes in High-Risk Brazilian Patients.

Increased genetic risk for melanoma can occur in the context of germline pathogenic variants in high-penetrance genes, such as CDKN2A and CDK4, risk variants in low- to moderate-penetrance genes (MC1R and MITF), and possibly due to variants in emerging genes, such as ACD, TERF2IP, and TERT. We aimed to identify germline variants in high- and low- to moderate-penetrance melanoma risk genes in Brazilian patients with clinical criteria for familial melanoma syndrome. We selected patients with three or more melanomas or melanoma patients from families with three tumors (melanoma and pancreatic cancer) in first- or second-degree relatives. Genetic testing was performed with a nine-gene panel (ACD, BAP1, CDK4, CDKN2A, POT1, TERT, TERF2IP, MC1R, and MITF). In 36 patients, we identified 2 (5.6%) with germline pathogenic variants in CDKN2A and BAP1 and 4 (11.1%) with variants of uncertain significance in the high-penetrance genes. MC1R variants were found in 86.5%, and both red hair color variants and unknown risk variants were enriched in patients compared to a control group. The low frequency of germline pathogenic variants in the high-penetrance genes and the high prevalence of MC1R variants found in our cohort show the importance of the MC1R genotype in determining the risk of melanoma in the Brazilian melanoma-prone families.

Multiple Primary Melanoma: A Five-Year Prospective Single-Center Follow-Up Study of Two MC1R R/R Genotype Carriers.

BACKGROUND: Multiple primary melanoma (MPM) is a diagnostic challenge even with ancillary imaging technologies available to dermatologists. In selected patients' phenotypes, the use of imaging approaches can help better understand lesion characteristics, and aid in early diagnosis and management. METHODS: Under a 5-year prospective single-center follow-up, 58 s primary melanomas (SPMs) were diagnosed in two first-degree relatives, with fair skin color, red hair, green eyes, and personal history of one previous melanoma each. Patients' behavior and descriptive demographic data were collected from medical records. The information on the first two primary melanomas (PMs) were retrieved from pathology reports. The characteristics of 60 melanomas were collected from medical records, video dermoscopy software, and pathology reports. Reflectance confocal microscopy (RCM) was performed prior to excision of 22 randomly selected melanomas. RESULTS: From February 2018 to May 2023, two patients underwent a pooled total of 214 excisional biopsies of suspect lesions, resulting in a combined benign versus malignant treatment ratio (NNT) of 2.0:1.0. The number of moles excised for each melanoma diagnosed (NNE) was 1.7:1.0 and 6.9:1.0 for the female and male patient respectively. The in-situ melanoma/invasive melanoma ratio (IIR) demonstrated a higher proportion of in-situ melanomas for both patients. From June 2018 to May 2023, a total of 58 SPMs were detected by the combination of total body skin exam (TBSE), total body skin photography (TBSP), digital dermoscopy (DD), and sequential digital dermoscopy imaging (SDDI) via comparative approach. The younger patient had her PM one month prior to the second and third cutaneous melanomas (CMs), characterizing a case of synchronous primary CM. The male older relative had a total of 7 nonsynchronous melanomas. CONCLUSIONS: This CM cohort is composed of 83.3% in-situ melanoma and 16.7% invasive melanoma. Both patients had a higher percentage of SPM with clinical nevus-like morphology (84.5%), global dermoscopic pattern of asymmetric multiple component (60.3%) and located on the lower limbs (46.6%). When RCM was performed prior to excision, 81% of SPM had features suggestive of malignancy. As well, invasive melanomas were more frequent in the lower limbs (40%). In the multivariate model, for the two high-risk patients studied, the chance of a not associated with nevus ("de novo") invasive SPM diagnosis is 25 times greater than the chance of a diagnosis of a nevus-associated invasive SPM.

Investigação de variantes genéticas germinativas nos pacientes com critério clínico para melanoma hereditário em acompanhamento no ambulatório de melanoma familial do núcleo de câncer de pele do ACCamargo Cancer Center: associação com características clínicas / Germline genetic testing in patients with clinical criteria for hereditary melanoma from the familial melanoma outpatient clinic of the skin cancer Department of ACCamargo Cancer Center: correlation with clinical features

Introdução: Cerca de 5 a 10% de todos os melanomas ocorrem em famílias com predisposição hereditária. A Síndrome do Melanoma Familial (SMF) é síndrome de câncer hereditário que confere predisposição ao melanoma cutâneo e caracteriza-se pela presença de múltiplos casos de melanoma na família ou múltiplos casos de melanoma no mesmo indivíduo, podendo estar associada a outras neoplasias como o carcinoma de pâncreas. Os genes de alta penetrância mais conhecidos, relacionados a SMF, são CDKN2A e CDK4. Ambos atuam no controle negativo do ciclo celular. As variantes patogênicas em CDKN2A correspondem a 10% das famílias com dois casos de melanoma e a 30 a 40% das famílias com 3 ou mais casos, apresentando associação com câncer de pâncreas. Na SMF a prevalência de variante em CDK4 varia de 1 a 3%. Mais recentemente, variantes patogênicas em novos genes de alta penetrância foram identificadas contribuindo com a caracterização de diferentes vias de susceptibilidade ao melanoma, incluindo genes relacionados a diferenciação celular, resposta a dano do DNA e manutenção dos telômeros, como os genes BAP1, POT1, ACD, TERF2IP e TERT. São ainda de grande importância na determinação de risco para o melanoma cutâneo, variantes em genes de baixa a moderada penetrância relacionados a pigmentação da pele e diferenciação dos melanócitos como os genes MC1R e MITF. Objetivos: Identificar variantes germinativas em genes de alta e baixa a moderada penetrância associados a risco aumentado para melanoma em pacientes com critérios clínicos para a SMF, associando os achados às características clínicas dos pacientes. Material e Métodos: Seleção de pacientes com três ou mais melanomas (melanomas primários múltiplos ­ MPM) ou pacientes com diagnóstico de melanoma com dois ou mais casos de melanoma ou câncer de pâncreas em parentes de primeiro ou segundo graus (melanoma familial ­ MF). O DNA genômico foi isolado a partir de sangue periférico ou saliva e realizado teste genético com painel customizado incluindo os genes ACD, BAP1, CDK4, CDKN2A, POT1, TERT, TERF2IP, MC1R e MITF. Foi realizada análise dos dados clínicos dos pacientes e histopatológicos dos seus tumores além de comparação entre os diferentes grupos (MPM x MF) e comparação das frequências de variantes no gene MC1R com grupo controle. Resultados: Foram incluídos 37 pacientes com média de idade ao diagnóstico de 40,1 anos, prevalência do fenótipo de pele clara (89,2%), cabelos e olhos claros (> 50% dos casos), além de grande número de pacientes com história de queimadura solar na infância (89,2%) e múltiplos nevos (> 75% com > 50 nevos). Total de 148 melanomas primários, com predomínio do tipo extensivo superficial (85,8%), localização mais frequente no tronco (52,7%) e maior prevalência de melanomas finos (96,7%). Foram encontrados dois pacientes (5,6%) com variantes patogênicas (P) e quatro (11,1%) com variantes de significado incerto (VUS), nos genes de alta penetrância estudados. As variantes P foram detectadas nos genes CDKN2A e BAP1. Variantes no gene MC1R foram encontradas em 33 casos (89,2%) com predomínio das variantes classificadas como RHC ou alelos R ­ variantes de moderada penetrância (51,4%). As variantes RHC, assim como as variantes MC1R de risco desconhecido (chamados alelos u), foram mais frequentes em nossa coorte quando comparados ao grupo controle. Discussão: A frequência de variantes patogênicas nos genes de alta penetrância estudados foi baixa, considerando-se os critérios utilizados para seleção dos probandos e do número de melanomas nos pacientes e seus familiares. Em algumas famílias, o risco aumentado para melanoma pode estar relacionado à presença dos alelos R ou dos alelos u de MC1R, combinação de duas variantes distintas de MC1R em alguns casos, associado muitas vezes a fenótipo e comportamento de risco. Conclusão: A baixa frequência de variantes nos genes de alta penetrância e a alta prevalência de variantes de MC1R encontradas em nossa coorte mostra a importância do genótipo de MC1R na determinação do risco de melanoma nas famílias brasileiras com critérios clínicos para a Síndrome do Melanoma Familial

Introduction: Approximately 5 to 10% of all melanoma cases occur in a familial context. Familial melanoma syndrome confers hereditary predisposition to cutaneous melanoma and other malignancies such as pancreatic carcinoma. It is characterized by families with multiple melanoma cases or individuals with multiple primary melanomas. CDKN2A and CDK4 were the first and second high-penetrance melanoma gene identified, respectively, both acting in cell cycle regulation. In general, CDKN2A pathogenic variants are found in 10 % of melanoma-prone families with two melanoma cases and in 30 to 40% of families with 3 or more cases, being associated with pancreatic cancer. The prevalence of CDK4 pathogenic variants varies from 1 to 3%. More recently, pathogenic variants in new high-penetrance genes have been identified, contributing to characterization of distinct melanoma susceptibility pathways, including genes related to cellular differentiation, response to DNA damage and maintenance of telomeres, such as BAP1, POT1, ACD, TERF2IP and TERT. Variants in low- to moderate-penetrance genes related to skin pigmentation and melanocytes differentiation, such as MC1R and MITF, are also of great importance in determining risk for cutaneous melanoma. Objectives: To identify germline variants in high and low- to moderate-penetrance genes associated with increased risk for melanoma in patients with clinical criteria for familial melanoma syndrome, and to correlate the findings with clinical features of the patients. Material and Methods: Patients diagnosed with three or more melanomas (multiple primary melanomas - MPM) or melanoma patients with two or more cases of melanoma or pancreatic cancer in first or second degree relatives (familial melanoma - FM). The genomic DNA was isolated from peripheral blood or saliva and genetic testing was performed using a panel including ACD, BAP1, CDK4, CDKN2A, POT1, TERT, TERF2IP, MC1R and MITF genes. We analyzed patients' clinical features and tumors' histopathological characteristics, comparing these findings between the two groups (MPM x FM). In addition, we performed comparison of MC1R variants frequencies between the cohort and the control group. Results: Thirty seven patients were included, with a mean age at diagnosis of 40.1 years, prevalence of the fair skin phenotype (89.2%), blond/red hair and light eyes (> 50%), history of childhood sunburn (89.2%) and multiple nevi (> 75% with > 50 nevi). A total of 148 primary melanomas were identified with a predominance of superficial spreading histological subtype (85.8%), location on the trunk (52.7%) and thin melanomas (96.7%). We identified two patients (5.6%) with pathogenic (P) variants and four patients (11.1%) with variants of uncertain significance (VUS) n the high-penetrance genes studied. The P variants were detected in CDKN2A and BAP1 genes. MC1R variants were found in 33 cases (89.2%) with a predominance of RHC variants or R alleles ­ moderate-penetrance variants (51.4%). The RHC variants as well as the unknown risk variants (the so-called u alleles) were more frequent in our cohort when compared to the control group. Discussion: The frequency of pathogenic variants in the high-penetrance genes studied was low, considering the proband selection criteria and the number of melanomas found in the patients and their families. In some families, the increased risk for melanoma may be related to the presence of the R alleles or the u alleles of MC1R, a combination of two distinct MC1R variants in some cases, both conditions often associated with phenotype and behavior of risk. Conclusion: The low frequency of pathogenic variants in the high-penetrance genes and the high prevalence of MC1R variants found in our cohort show the importance of MC1R genotype in determining the risk of melanoma in the Brazilian melanoma-prone families

BAP1 tumor predisposition syndrome case report: pathological and clinical aspects of BAP1-inactivated melanocytic tumors (BIMTs), including dermoscopy and confocal microscopy.

BACKGROUND: BRCA1 associated-protein 1 (BAP1) tumor predisposition syndrome is associated with an increased risk for malignant mesotheliomas, uveal and cutaneous melanomas, renal cell carcinomas, and singular cutaneous lesions. The latter are referred to as BAP1-inactivated melanocytic tumors (BIMTs). When multiple BIMTs manifest, they are considered potential markers of germline BAP1 mutations. CASE PRESENTATION: Here, we report a novel pathogenic BAP1 germline variant in a family with a history of BIMTs, cutaneous melanomas, and mesotheliomas. We also describe singular pathological aspects of the patient's BIMT lesions and their correlation with dermoscopic and reflectance confocal microscopy findings. CONCLUSIONS: This knowledge is crucial for the recognition of BIMTs by dermatologists and pathologists, allowing the determination of appropriate management for high-risk patients, such as genetic investigations and screening for potentially aggressive tumors.