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BACKGROUND: Cutaneous malignant melanoma (CMM) is one of the most common skin cancers worldwide. Limited information is available in the current scientific literature on the concordance of genetic alterations between primary and metastatic CMM. In the present study, we performed next-generation sequencing (NGS) analysis of the main genes participating in melanoma pathogenesis and progression, among paired primary and metastatic lesions of CMM patients, with the aim to evaluate levels of discrepancies in mutational patterns. METHODS: Paraffin-embedded tumor tissues of the paired lesions were retrieved from the archives of the institutions participating in the study. NGS was performed using a specific multiple-gene panel constructed by the Italian Melanoma Intergroup (IMI) to explore the mutational status of selected regions (343 amplicons; amplicon range: 125-175 bp; coverage 100%) within the main 25 genes involved in CMM pathogenesis; sequencing was performed with the Ion Torrent PGM System. RESULTS: A discovery cohort encompassing 30 cases, and a validation cohort including eleven Sardinian patients with tissue availability from both the primary and metachronous metastatic lesions were identified; the global number of analyzed tissue specimens was 90. A total of 829 genetic non-synonymous variants were detected: 101 (12.2%) were pathogenic/likely pathogenic, 131 (15.8%) were benign/likely benign, and the remaining 597 (72%) were uncertain/unknown significance variants. Considering the global cohort, the consistency in pathogenic/pathogenic like mutations was 76%. Consistency for BRAF and NRAS mutations was 95.2% and 85.7% respectively, without statistically significant differences between the discovery and validation cohort. CONCLUSIONS: Our study showed a high level of concordance in mutational patterns between primary and metastatic CMM, especially when pathogenic mutations in driver genes were considered.
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Sequenciamento de Nucleotídeos em Larga Escala/métodos , Melanoma/genética , Melanoma/patologia , Mutação/genética , Estudos de Coortes , Feminino , GTP Fosfo-Hidrolases/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Proto-Oncogênicas B-raf/genéticaRESUMO
INTRODUCTION: Multiple primary melanomas (MPM) occur up to 8% of patients with cutaneous malignant melanoma (CMM). They are often sporadic harbouring several somatic mutations, but also familial cases harbouring a CDKN2A germline mutation have been describe in Caucasian populations. The aim of this study was to investigate the incidence, the distribution patterns and the impact of known and unknown germline and somatic mutations in patients with MPM from Italy. MATERIALS AND METHODS: One-hundred and two MPM patients were enrolled for germline mutation analysis, and five patients with at least four MPMs were identified for somatic mutation analysis. The demographic, pathologic and clinical features were retrieved from medical records. Molecular analysis for both germline and somatic mutations was performed in genomic DNA from peripheral blood and tissue samples, respectively, through a next generation sequencing approach, using a specific multiple-gene panel constructed by the Italian Melanoma Intergroup for somatic analysis and a commercial cancer hotspot panel for somatic analysis. RESULTS: CDKN2A mutations were detected in 6/16 (37.5%) and 3/86 (3.5%) MPM cases with and without family history for melanoma, respectively. Furthermore, multiple MC1R and, to a lesser extent, ATM variants have been identified. BAP1 variants were found only in MPM patients from southern Italy. The most frequent somatic variants were the pathogenic BRAFV600E and TP53, followed by KIT, PIK3CA, KDR, and NRAS. Single APC, ERBB4, MET, JAK3 and other variants with unknown function were also detected. CONCLUSIONS: CDNK2A mutation is the most relevant susceptibility mutation in Italian patients with MPM, especially those with a family history for CMM. The prevalence of this mutation and other sequence variants identified in this study varies among specific sub-populations. Furthermore, some heterogeneity in driver somatic mutations between sporadic MPMs has been observed, as well as in a number of associated sequence variants the clinical impact of which needs to be further elucidated.
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Mutação em Linhagem Germinativa/genética , Sequenciamento de Nucleotídeos em Larga Escala , Melanoma/genética , Neoplasias Primárias Múltiplas/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Carcinogênese/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , Seguimentos , Amplificação de Genes/genética , Frequência do Gene/genética , Loci Gênicos/genética , Predisposição Genética para Doença , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Melanoma Maligno CutâneoRESUMO
BACKGROUND: Activated PI3K-AKT pathway may contribute to decrease sensitivity to inhibitors of key pathogenetic effectors (mutated BRAF, active NRAS or MEK) in melanoma. Functional alterations are deeply involved in PI3K-AKT activation, with a minimal role reported for mutations in PIK3CA, the catalytic subunit of the PI3K gene. We here assessed the prevalence of the coexistence of BRAF/NRAS and PIK3CA mutations in a series of melanoma samples. METHODS: A total of 245 tumor specimens (212 primary melanomas and 33 melanoma cell lines) was screened for mutations in BRAF, NRAS, and PIK3CA genes by automated direct sequencing. RESULTS: Overall, 110 (44.9%) samples carried mutations in BRAF, 26 (10.6%) in NRAS, and 24 (9.8%) in PIK3CA. All identified PIK3CA mutations have been reported to induce PI3K activation; those detected in cultured melanomas were investigated for their interference with the antiproliferative activity of the BRAF-mutant inhibitor vemurafenib. A reduced suppression in cell growth was observed in treated cells carrying both BRAF and PIK3CA mutations as compared with those presenting a mutated BRAF only. Among the analysed melanomas, 12/245 (4.9%) samples presented the coexistence of PIK3CA and BRAF/NRAS mutations. CONCLUSIONS: Our study further suggests that PIK3CA mutations account for a small fraction of PI3K pathway activation and have a limited impact in interfering with the BRAF/NRAS-driven growth in melanoma.
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GTP Fosfo-Hidrolases/genética , Melanoma/genética , Proteínas de Membrana/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Alterations in key-regulator genes of disease pathogenesis (BRAF, cKIT, CyclinD1) have been evaluated in patients with multiple primary melanoma (MPM). METHODS: One hundred twelve MPM patients (96 cases with two primary melanomas, 15 with three, and 1 with four) were included into the study. Paired synchronous/asynchronous MPM tissues (N=229) were analyzed for BRAF mutations and cKIT/CyclynD1 gene amplifications. RESULTS: BRAF mutations were identified in 109/229 (48%) primary melanomas, whereas cKIT and CyclinD1 amplifications were observed in 10/216 (5%) and 29/214 (14%) tumor tissues, respectively. While frequency rates of BRAF mutations were quite identical across the different MPM lesions, a significant increase of cKIT (p<0.001) and CyclinD1 (p=0.002) amplification rates was observed between first and subsequent primary melanomas. Among the 107 patients with paired melanoma samples, 53 (49.5%) presented consistent alteration patterns between first and subsequent primary tumors. About one third (40/122; 32.8%) of subsequent melanomas presented a discrepant pattern of BRAF mutations as compared to incident primary tumors. CONCLUSIONS: The low consistency in somatic mutation patterns among MPM lesions from same patients provides further evidence that melanomagenesis is heterogeneous and different cell types may be involved. This may have implications in clinical practice due to the difficulties in molecularly classifying patients with discrepant primary melanomas.
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Ciclina D1/genética , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-kit/genética , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , MutaçãoRESUMO
BACKGROUND: Prevalence and distribution of pathogenetic mutations in BRAF and NRAS genes were evaluated in multiple melanoma lesions from patients with different geographical origin within the same Italian population. METHODS: Genomic DNA from a total of 749 tumor samples (451 primary tumors and 298 metastases) in 513 consecutively-collected patients with advanced melanoma (AJCC stages III and IV) was screened for mutations in exon 15 of BRAF gene and, at lower extension (354/513; 69%), in the entire coding DNA of NRAS gene by automated direct sequencing. Among tissues, 236 paired samples of primary melanomas and synchronous or asynchronous metastases were included into the screening. RESULTS: Overall, mutations were detected in 49% primary melanomas and 51% metastases, for BRAF gene, and 15% primary tumors and 16% secondaries, for NRAS gene. A heterogeneous distribution of mutations in both genes was observed among the 451 primary melanomas according to patients' geographical origin: 61% vs. 42% (p = 0.0372) BRAF-mutated patients and 2% vs. 21% (p < 0.0001) NRAS-mutated cases were observed in Sardinian and non-Sardinian populations, respectively. Consistency in BRAF/NRAS mutations among paired samples was high for lymph node (91%) and visceral metastases (92.5%), but significantly lower for brain (79%; p = 0.0227) and skin (71%; p = 0.0009) metastases. CONCLUSIONS: Our findings about the two main alterations occurring in the different tumor tissues from patients with advanced melanoma may be helpful in improving the management of such a disease.
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GTP Fosfo-Hidrolases/genética , Melanoma/genética , Melanoma/patologia , Proteínas de Membrana/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Feminino , Genes Neoplásicos/genética , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prevalência , Adulto JovemRESUMO
BACKGROUND: Racial and geographic factors seem to affect the incidence of cutaneous and mucosal melanoma. OBJECTIVE: To investigate the occurrence of BRAF and cKIT impairments in patients with sinonasal melanoma in Southern Italy. METHODS: Eleven sinonasal melanomas were screened for BRAF mutations and cKIT alterations by immunohistochemistry (CD117), fluorescence in situ hybridization and sequencing analyses. RESULTS: A high prevalence (4/11; 36%) of BRAF mutations and lack of cKIT mutations were observed. Amplification of cKIT was found in 18% of cases; cKIT expression was detectable in 18% non-overlapping cases. No correlation between CD117 and cKIT alterations was observed. One (6%) cKIT and two (12%) BRAF mutations were detected in an additional series of 17 acral/mucosal melanomas from the same geographic areas. CONCLUSION: Mutations of cKIT are infrequent in sinonasal melanoma in Southern Italy.
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Neoplasias do Seio Maxilar/genética , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-kit/genética , Neoplasias Cutâneas/genética , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Ânus/genética , Neoplasias da Coroide/genética , Neoplasias da Túnica Conjuntiva/genética , Análise Mutacional de DNA , Feminino , Amplificação de Genes , Humanos , Itália , Masculino , Neoplasias do Seio Maxilar/patologia , Melanoma/química , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Mucosa , Mutação , Proteínas Proto-Oncogênicas c-kit/análise , Estudos Retrospectivos , Neoplasias Vulvares/genética , População Branca/genéticaRESUMO
UNLABELLED: Anaplastic large cell lymphoma (ALCL) of the breast is a very rare nonepithelial neoplasm. In the literature, this tumor has sometimes been described in proximity of breast implants (60 implant-related ALCL reported). In 2010, a patient who had undergone a right mastectomy and tissue expander/implant reconstruction for a "ductal" carcinoma 10 years before was referred to our unit for evaluation. On examination, an enlarged reconstructed right breast was found. The reconstructed breast did not show tenderness or signs of infection, ulceration, or breakdown. Mammograms and ultrasound scan did not suggest the presence of recurrent cancer, infection, deflation of the implant, or severe capsule contracture. The patient underwent mammary implant replacement. About 3 weeks after surgery, the patient came back to our unit for a new mild enlargement of the operated breast and the implant was removed. Three months later, the patient returned with a skin lesion in the right parasternal region. A radical excisional biopsy was performed under local anesthesia and the diagnosis of ALK-1-negative ALCL was finally made. The clinical and histological diagnosis of this disease is difficult as it can often be mistaken for a simple seroma (breast enlargement), an infection, or an unspecific reaction to silicone (redness and/or tension of the skin, itching, and fever). We strongly suggest considering ALCL in any patient with a spontaneous breast seroma lasting more than 6 months after mammary prosthesis implantation. The suspicion of ALCL must be suggested to the pathologist immediately. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Implantes de Mama , Neoplasias da Mama/patologia , Linfoma Anaplásico de Células Grandes/patologia , Receptores de Activinas Tipo II/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Contratura Capsular em Implantes/patologia , Linfoma Anaplásico de Células Grandes/metabolismo , Pessoa de Meia-Idade , Seroma/patologiaRESUMO
Malignant melanoma (MM) is one of the deadliest skin cancers. BRAF mutation status plays a predominant role in the management of MM patients. The aim of this study was to compare BRAF mutational testing performed by conventional nucleotide sequencing approaches with either real-time polymerase chain reaction (rtPCR) or next-generation sequencing (NGS) assays in a real-life, hospital-based series of advanced MM patients. Consecutive patients with AJCC (American Joint Committee on Cancer) stage IIIC and IV MM from Sardinia, Italy, who were referred for molecular testing, were enrolled into the study. Initial screening was performed to assess the mutational status of the BRAF and NRAS genes, using the conventional methodologies recognized by the nationwide guidelines, at the time of the molecular classification, required by clinicians: at the beginning, Sanger-based sequencing (SS) and, after, pyrosequencing. The present study was then focused on BRAF mutation detecting approaches only. BRAF wild-type cases with available tissue and adequate DNA were further tested with rtPCR (Idylla™) and NGS assays. Globally, 319 patients were included in the study; pathogenic BRAF mutations were found in 144 (45.1%) cases examined with initial screening. The rtPCR detected 11 (16.2%) and 3 (4.8%) additional BRAF mutations after SS and pyrosequencing, respectively. NGS detected one additional BRAF-mutated case (2.1%) among 48 wild-type cases previously tested with pyrosequencing and rtPCR. Our study evidenced that rtPCR and NGS were able to detect additional BRAF mutant cases in comparison with conventional sequencing methods; therefore, we argue for the preferential utilization of the aforementioned assays (NGS and rtPCR) in clinical practice, to eradicate false-negative cases and improve the accuracy of BRAF detection.
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Cutaneous malignant melanoma is a heterogeneous disease, being the consequence of specific genetic alterations along several molecular pathways. Despite the increased knowledge about the biology and pathogenesis of melanoma, the incidence has grown markedly worldwide, making it extremely important to develop preventive measures. The beneficial role of correct nutrition and of some natural dietary compounds in preventing malignant melanoma has been widely demonstrated. This led to numerous studies investigating the role of several dietary attitudes, patterns, and supplements in the prevention of melanoma, and ongoing research investigates their impact in the clinical management and outcomes of patients diagnosed with the disease. This article is an overview of recent scientific advances regarding specific dietary compounds and their impact on melanoma development and treatment.
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Sinonasal mucosal melanoma (SNM) is a rare and aggressive type of melanoma, and because of this, we currently have a limited understanding of its genetic and molecular constitution. The incidence among SNMs of somatic mutations in the genes involved in the main molecular pathways, which have been largely associated with cutaneous melanoma, is not yet fully understood. Through a next-generation sequencing (NGS) approach using a panel of 25 genes involved in melanoma pathogenesis customized by our group, we performed a mutation analysis in a cohort of 25 SNM patients. Results showed that pathogenic mutations were found in more than 60% of SNM cases at a somatic level, with strikingly 32% of them carrying deleterious mutations in the BRAF gene. The identified mutations mostly lack the typical UV signature associated with cutaneous melanomas and showed no significant association with any histopathological parameter. Oncogenic activation of the BRAF-depending pathway, which may induce immune tolerance into the tumour microenvironment (i.e., by increasing the VEGF production) was poorly associated with mutations in genes that have been related to diminished clinical benefit of the treatment with BRAF inhibitors. Screening for mutations in BRAF and other MAPK genes should be included in the routine diagnostic test for a better classification of SNM patients.
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BACKGROUND: Elastosis perforans serpiginosa (EPS) is an uncommon cutaneous disorder classified under perforating diseases (PD); a group of dermatoses with transepidermal extrusion of collagen or elastic tissue. Three EPS subtypes have been reported that differ according to aetiology, associated diseases, and histopathological features. Herein, we report a systematic review of the literature, as well as a case of a 41-year-old woman with Wilson disease treated with penicillamine (PCM), who developed EPS after 11 years of drug intake. OBJECTIVES: To analyse and characterise EPS subtypes based on an evaluation of potential different histological patterns. MATERIALS & METHODS: A systematic literature search in Pubmed was performed to identify articles describing EPS. RESULTS: A peculiar histological pattern was identified in EPS PCM-related patients, either in affected or unaffected skin samples. Using specific elastic fibre stains (Verhoeff-van Gieson, Weigert, and Orcein), fibres appeared with an irregular surface with thorn-like protrusion, probably due to weaker fibre cross-links, making them unable to re-expand after contraction along their long axis. Interestingly, similar histological patterns have also been reported in elastic tissues of vessel walls of the lungs and upper respiratory tract, joints, visceral adventitia, and kidney. CONCLUSIONS: A distinctive histological pattern of PCM-related EPS is observed in affected and normal-appearing skin, as well as extracutaneous elastic tissue, suggesting serious potential widespread drug-induced systemic elastolytic damage.
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Quelantes/efeitos adversos , Penicilamina/efeitos adversos , Dermatopatias/induzido quimicamente , Dermatopatias/patologia , Adulto , Animais , Feminino , Degeneração Hepatolenticular/tratamento farmacológico , Humanos , Dermatopatias/classificaçãoRESUMO
Cutaneous melanoma is one of the most frequent malignancies of the skin in Caucasian populations. Patients who develop cutaneous melanoma are at increased risk of developing a second primary melanoma. The estimated incidence of multiple primary melanoma (MPM) ranges from 1.2% to 8.2% of cases, with a high preponderance of melanomas occurring metachronously. The aim of this study was to describe dermoscopic, microscopic, clinical, and molecular correlations between first and subsequent melanomas in patients with metachronous MPMs. Twenty-four paired melanomas from 12 MPM patients were evaluated for architectural characteristics based on dermoscopy and confocal microscopy, as well as for mutations in BRAF and NRAS genes by Sanger-based sequencing analysis. Specific scores used for classifying features of dermoscopy (global pattern; 7-point check list; ABCD Stolz score) and confocal microscopy (Segura and Pellacani) were compared with genetic and histological data. Consistency in dermoscopic patterns between the primary and subsequent cutaneous melanomas were observed in about two thirds of cases, whereas concordant features based on confocal microscopy were found in only about two fifths of cases. The majority of patients (7/12; 58%) presented consistent BRAF/NRAS mutation patterns between first and subsequent primary melanomas. A significant association between BRAF mutations and Pellacani score was evident. Similarities between the index melanoma and subsequent cutaneous melanomas were observed with regards to dermoscopic features and, to a much less extent, confocal microscopy findings. Our data further indicate that the Pellacani score may be used to predict BRAF mutations.
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Genes ras/genética , Melanoma/genética , Melanoma/patologia , Mutação , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Dermoscopia , Feminino , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-IdadeRESUMO
Cutaneous melanoma is a common and aggressive human skin cancers. Much is actually known about the molecular mechanisms underlying melanoma pathogenesis. The aim of the study was to evaluate any possible correlation between mutations in main growth-controlling genes (BRAF, NRAS, CDKN2A) and copy number variations in frequently amplified candidate genes (MITF, EGFR, CCND1, cMET, and cKIT) during melanoma initiation and progression. A large series of primary and secondary melanoma tissue samples (N = 274) from 232 consecutively-collected patients of Italian origin as well as 32 tumor cell lines derived from primary and metastatic melanomas underwent mutation screening and fluorescence in situ hybridization (FISH) analysis. Overall, BRAF, NRAS, and CDKN2A were found mutated in 62.5%, 12.5% and 59% cell lines and in 47%, 16%, 12% tumor tissues, respectively. Quite identical mutation patterns between primary tumors and metastatic lesions were found for BRAF and NRAS genes; mutations of CDKN2A gene appeared to be instead selected during tumor progression. In cell lines, high rates of gene amplifications were observed (varying from 12.5% for cKIT to 50% for MITF); vast majority of cell lines (75%) presented at least one amplified gene. Conversely, prevalence of gene amplification was significantly and progressively decreasing in melanoma metastases (12%) and primary melanomas (4%). Our findings suggest that gene amplifications may be acquired during the late phases of melanoma evolution and mostly act as "passenger" or "non-causative" alterations.
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Clinical predictors for germline mutations of candidate genes in large clinic based population of patients with cutaneous malignant melanoma (CMM) are widely awaited. Using denaturing high-performance liquid chromatography (DHPLC) analysis and DNA sequencing, 557 consecutively-collected CMM patients originating from South Italy were screened for CDKN2A germline mutations; subsets of them were screened for mutations in the BRAF and BRCA2 genes. Seven CDKN2A mutations were detected in 14 (2.5%) CMM patients. Relative risk of carrying a CDKN2A mutation for CMM patients was demonstrated to significantly increase with the presence of familial recurrence of melanoma (risk ratio (RR)=6.31; p=0.0009), multiple primary melanomas (RR=3.43; p=0.0014), and early onset age (RR=4.56; p=0.0026). All CDKN2A mutations were observed in non-Sardinian patients (14/441; 3.2%), whereas BRAF and BRCA2 genes were found mutated in Sardinian patients (3/116; 2.6%). Such indicators of the presence of CDKN2A mutations will be useful in counselling patients about undergoing genetic testing. Our findings strongly suggest that mutation rates of candidate cancer genes may deeply vary among CMM patients from different geographical areas.
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Genes BRCA2 , Genes p16 , Mutação em Linhagem Germinativa/genética , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Adulto , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA , Feminino , Testes Genéticos , Humanos , Itália/epidemiologia , Masculino , Melanoma/epidemiologia , Pessoa de Meia-Idade , Análise de Regressão , Neoplasias Cutâneas/epidemiologiaRESUMO
The aim of this report was to study the descriptive and genetic epidemiology of malignant melanoma in North Sardinia, Italy, in the period 1992-2011. Epidemiological data were obtained from the local tumor registry, which is part of the Italian Association for Tumor Registries. Among patients included in the North Sardinia tumor registry, 316 patients first evaluated for familial recurrence of melanoma were submitted to mutation analysis in CDKN2A and CDK4 genes. The overall number of cases registered was 532. The male-to-female ratio was 1 : 1 and the mean age was 56 years for men and 55 years for women. The standardized incidence rates were 4.9/100 000 and 4.4/100 000 and the standardized mortality rates were 1.7/100 000 and 1.3/100 000 for men and women, respectively. The relative 5-year survival was 77% for men and 79% for women. In our series, 24/316 (7.6%) patients had a familial occurrence of melanoma (presence of at least one additional family member affected). Among these, one variant (Gly23Asp), reported previously as a low-frequency disease-causing mutation, was detected by mutational screening in the p16 gene only. With the exception of polymorphisms, none of either the sporadic melanoma patients or healthy controls presented a germline mutation in candidate genes. An increase in incidence and a decrease in mortality rates of malignant melanoma were registered in North Sardinia, from 1992 to 2011, whereas survival was similar to that reported in recent international reports. The high-penetrance melanoma susceptibility genes (CDKN2A and CDK4) are not involved in predisposition to melanoma in North Sardinia.
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Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Melanoma/epidemiologia , Melanoma/genética , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Itália/epidemiologia , Masculino , Melanoma/diagnóstico , Pessoa de Meia-Idade , Neoplasias Cutâneas/diagnóstico , Adulto JovemRESUMO
PURPOSE: Ocogenic activation of the BRAF gene has been demonstrated to be involved in the pathogenesis of malignant melanoma (MM). In this study, we investigated the contribution of BRAF to melanoma susceptibility, also making a comparison with frequency of CDKN2A germline mutations in MM patients from different areas in Italy. PATIENTS AND METHODS: sing a combination of denaturing high-performance liquid chromatography analysis and automated sequencing on genomic DNA from peripheral blood or tumor tissue samples, 569 MM patients (211 from northern Italy and 358 from southern Italy) were screened for BRAF mutations. RESULTS: Three BRAF germline sequence variants (M116R, V599E, and G608H) were identified in four (0.7%) of 569 MM patients. The most common BRAF mutation, V599E, was detected in one germline DNA sample only; M116R and G608H were newly described mutations. A high frequency (59%) of BRAF mutations was instead observed in tumor samples from patients also undergoing germline DNA analysis; at the somatic level, substitution of valine 599 was found to account for the majority (88%) of BRAF mutations. We then estimated the germline mutation rates in BRAF and CDKN2A among 358 consecutively collected patient samples originating in southern Italy; a low (2.5%) or very low (0.29%) prevalence of CDKN2A and BRAF mutations, respectively, was detected. CONCLUSION: utation analysis of either blood DNA from a large collection of MM patients or matched MM tissues from a subset of such patients revealed that BRAF is somatically mutated and does not play a major role in melanoma susceptibility. The present study further suggests that patient origin may account for different mutation rates in candidate genes.
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Predisposição Genética para Doença , Melanoma/genética , Proteínas Proto-Oncogênicas c-raf/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , DNA de Neoplasias/análise , Feminino , Mutação em Linhagem Germinativa , Humanos , Itália , Masculino , Melanoma/etiologia , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas B-raf , Fatores de Risco , Neoplasias Cutâneas/etiologiaRESUMO
Inflammatory pseudotumor (IPT) and follicular dendritic reticulum cell tumor (FDRCT) are rare entities of the lymph node characterized by spindle-cell proliferation. We report a case of a 31-year-old woman, who was admitted for biopsy of a lymph node in the left submandibular area. The microscopic examination revealed a proliferation of spindle cells, partially replacing the normal lymph node architecture, suggestive of an IPT. The preserved peripheral portion showed follicular hyperplasia with Castleman-like appearance. Six years later she presented with a new enlargement in the same submandibular area. The nodule was removed, and a diagnosis of a classic FDRCT of the lymph node was made. The present case is remarkable, and clinicopathological data show that IPT-like proliferations could be in some case an early presentation of FDRCT.