RESUMO
Multiple endocrine neoplasia type 2 is characterized by germline mutations in RET. For exon 10, comprehensive molecular and corresponding phenotypic data are scarce. The International RET Exon 10 Consortium, comprising 27 centers from 15 countries, analyzed patients with RET exon 10 mutations for clinical-risk profiles. Presentation, age-dependent penetrance, and stage at presentation of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism were studied. A total of 340 subjects from 103 families, age 4-86, were registered. There were 21 distinct single nucleotide germline mutations located in codons 609 (45 subjects), 611 (50), 618 (94), and 620 (151). MTC was present in 263 registrants, pheochromocytoma in 54, and hyperparathyroidism in 8 subjects. Of the patients with MTC, 53% were detected when asymptomatic, and among those with pheochromocytoma, 54%. Penetrance for MTC was 4% by age 10, 25% by 25, and 80% by 50. Codon-associated penetrance by age 50 ranged from 60% (codon 611) to 86% (620). More advanced stage and increasing risk of metastases correlated with mutation in codon position (609â620) near the juxtamembrane domain. Our data provide rigorous bases for timing of premorbid diagnosis and personalized treatment/prophylactic procedure decisions depending on specific RET exon 10 codons affected.
Assuntos
Éxons , Mutação em Linhagem Germinativa/genética , Neoplasia Endócrina Múltipla Tipo 2a/genética , Penetrância , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Adolescente , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Neuroendócrino , Criança , Pré-Escolar , Códon/genética , Feminino , Humanos , Hiperparatireoidismo/genética , Hiperparatireoidismo/patologia , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 2a/patologia , Estadiamento de Neoplasias , Feocromocitoma/genética , Feocromocitoma/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto JovemRESUMO
Pancreatic islet cell tumors (ICTs) occur as sporadic neoplasias or as a manifestation of multiple endocrine neoplasia type 1 (MEN1) and von Hippel-Lindau disease (VHL). Molecular classification of ICTs is mandatory for timely diagnosis and surveillance. Systematic comparison of VHL-ICTs and sporadic ICTs has been lacking. Our registry-based approaches used the German NET-Registry with 259 patients with neuroendocrine tumors (NETs), who were primarily diagnosed with NETs, and the German VHL-Registry with 485 molecular genetically confirmed patients who had undergone magnetic resonance imaging or computed tomography of the abdomen. All patients provided blood DNA for testing of the MEN1 and VHL genes for intragenic mutations and large deletions. In the NET-Registry, 9/101 patients (8.9%) with ICTs had germline mutations, 8 in MEN1 and 1 in VHL. In the VHL-Registry, prevalence of NETs was 52/487 (10.6%), and all were ICTs. Interestingly, of those with VHL p.R167W, 47% developed ICTs, compared to 2% of those with p.Y98H. In total, there were 92 truly sporadic, i.e. mutation-negative ICT patients. Comparing these with the 53 VHL-ICT patients, the statistically significant differences were predominance of female gender (P=0.01), multifocal ICTs (P=0.0029), and lower malignancy rate (P<0.001) in VHL-ICTs compared to sporadic cases. VHL was prevalent in <0.5% of NETs, while NETs occur in â¼10% of VHL, virtually exclusively as ICTs, which are rarely the first presentation. Patients with NETs should not be subjected to genetic testing of the VHL gene, unless they have multifocal ICTs, other VHL-associated tumors, and/or a family history for VHL.
Assuntos
Neoplasia Endócrina Múltipla Tipo 1/genética , Doença de von Hippel-Lindau/genética , Adenoma de Células das Ilhotas Pancreáticas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , DNA de Neoplasias/química , DNA de Neoplasias/genética , Feminino , Variação Genética , Mutação em Linhagem Germinativa , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/epidemiologia , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/genética , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Adulto Jovem , Doença de von Hippel-Lindau/epidemiologiaRESUMO
RET testing in multiple endocrine neoplasia type 2 for molecular diagnosis is the paradigm for the practice of clinical cancer genetics. However, precise data for distinct mutation-based risk profiles are not available. Here, we survey the clinical profile for one specific genotype as a model, TGC to TGG in codon 634 (C634W). By international efforts, we ascertained all available carriers of the RET C634W mutation. Age at diagnosis, penetrance, and clinical complications were analyzed for medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism (HPT), as well as overall survival. Our series comprises 92 carriers from 20 unrelated families worldwide. Sixty-eight subjects had MTC diagnosed at age 3-72 years (mean 29). Lymph node metastases were observed in 16 subjects aged 20-72 and distant metastases in 4 subjects aged 28-69. Forty-one subjects had pheochromocytoma detected at age 18-67 (mean 36). Amongst the 28 subjects with MTC and pheochromocytoma, six developed pheochromocytoma before MTC. Six subjects had HPT diagnosed at age 26-52 (mean 39). Eighteen subjects died; of the 16 with known causes of death, 8 died of pheochromocytoma and 4 of MTC. Penetrance for MTC is 52% by age 30 and 83% by age 50, for pheochromocytoma penetrance is 20% by age 30 and 67% by age 50, and for HPT penetrance is 3% by age 30 and 21% by age 50. These data provide, for the first time, RET C634W-specific neoplastic risk and age-related penetrance profiles. The data may facilitate risk assessment and genetic counseling.
