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BACKGROUND: Evidence that germline mutations in the RET proto-oncogene are the underlying cause of the familial form of medullary thyroid carcinoma (MTC) made it possible to identify gene carriers with a very high degree of accuracy. Aiming to define the mutational profile observed in our patients and to assess gene carriers' compliance with an early surgery, we reviewed results of molecular analysis of RET performed at our institution since 1994. METHODS: One hundred fifty-eight individuals were screened for germline mutations of the RET proto-oncogene. Seventy-seven patients had apparently sporadic MTC; 8 patients had both MTC and pheochromocytoma or MTC and clinical features of multiple endocrine neoplasia type 2B despite a negative family history; 8 patients were known to belong to affected kindreds; and 65 individuals were at-risk individuals to develop MTC. RESULTS: A germline mutation in RET was identified in 4% of apparently sporadic MTC patients, in 100% of patients with MTC and pheochromocytoma or MTC and clinical features of multiple endocrine neoplasia type 2B, and in 100% of probands of clinically established kindreds. The most affected codon was 634 (58%) followed by codon 804 (16%). Among at-risk individuals, 49% were identified as gene carriers. Seven individuals were submitted to prophylactic thyroidectomy (mean age, 17.7 +/- 12.5 years; range: 3-42 years), and all but 1 had MTC. CONCLUSIONS: RET mutational spectrum observed in the present population disclosed a higher frequency of codon 804 mutations than expected. Compliance with an early prophylactic surgery seemed to be influenced not only by medical advice and cultural factors but also by the aggressiveness of disease in gene carriers' families.
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Mutación de Línea Germinal , Proteínas Proto-Oncogénicas c-ret/genética , Proto-Oncogenes , Tiroidectomía , Adolescente , Neoplasias de las Glándulas Suprarrenales/genética , Adulto , Secuencia de Bases , Instituciones Oncológicas , Carcinoma Medular/genética , Carcinoma Medular/prevención & control , Niño , Preescolar , Análisis Mutacional de ADN , ADN de Neoplasias/genética , Femenino , Tamización de Portadores Genéticos , Humanos , Masculino , Neoplasia Endocrina Múltiple Tipo 2b/genética , Feocromocitoma/genética , Portugal , Proto-Oncogenes Mas , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/prevención & controlRESUMEN
BACKGROUND: Secondary involvement of the thyroid gland is rare. Often the origin of the tumor is difficult to identify from the material obtained by fine-needle aspiration cytology. Renal cell carcinoma of the clear-cell type is one of the more common carcinomas to metastasize to the thyroid gland. Somatic mutations of the von Hippel-Lindau tumor suppressor gene are associated with the sporadic form of this tumor. We aimed to illustrate the potential utility of DNA based technologies to search for specific molecular markers in order to establish the anatomic site of origin. CASE PRESENTATION: A 54-yr-old Caucasian male complaining of a rapidly increasing neck tumor was diagnosed as having a clear-cell tumor by fine-needle aspiration cytology. A positive staining for cytokeratin as well as for vimentin and CD10 in the absence of staining for thyroglobulin, calcitonin and TTF1 suggested a renal origin confirmed by computed tomography. Using frozen RNA, obtained from cells left inside the needle used for fine needle aspiration cytology, it was possible to identify a somatic mutation (680 delA) in the VHL gene. CONCLUSION: In the presence of a clear-cell tumor of the thyroid gland, screening for somatic mutations in the VHL gene in material derived from thyroid aspirates might provide additional information to immunocytochemical studies and therefore plays a contributory role to establish the final diagnosis. Moreover, in a near future, this piece of information might be useful to define a targeted therapy.
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OBJECTIVE: There is increasing evidence involving prolactin (PRL) and its receptor (PRLR) in the development of different cancers. The aim of the present study was to investigate the expression of PRLR and PRL in human thyroid tissues. DESIGN AND METHODS: Using tissue microarray (TMA) by immunohistochemical staining, we examined the expression level of PRLR and PRL in 314 specimens from 71 thyroid cancer patients and 15 normal thyroid samples. RESULTS: Expression of the PRLR was observed in 93.3% of normal thyroid samples and in 76.1% of all thyroid cancers, while expression of PRL was observed in only 10% of medullary thyroid carcinomas and not at all in the other specimens, whether normal or neoplastic. Moreover, results suggested an overexpression of PRLR in 70% of medullary thyroid carcinomas, whereas 53.3% of poorly differentiated thyroid carcinomas showed a negative pattern of staining (p = 0.014 vs normal). CONCLUSIONS: Present data revealed, for the first time, a widespread expression of PRLR in normal and neoplastic human thyroid tissues as well as a scarce expression of PRL, observed only in a few medullary thyroid carcinomas. Whether the overexpression of PRLR observed in medullary thyroid carcinomas or the underexpression of PRLR observed in poorly differentiated thyroid carcinomas play a contributory role in the oncogenesis of these tumors remains to be determined.
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Carcinoma Medular/metabolismo , Prolactina/metabolismo , Receptores de Prolactina/metabolismo , Glándula Tiroides/metabolismo , Neoplasias de la Tiroides/metabolismo , Carcinoma Medular/patología , Humanos , Inmunohistoquímica , ARN Mensajero/metabolismo , Receptores de Prolactina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Glándula Tiroides/anatomía & histología , Glándula Tiroides/patología , Neoplasias de la Tiroides/patología , Análisis de Matrices TisularesRESUMEN
INTRODUCTION: In the last years, the global context of medical education and Medical Residency programs in Portugal suffered substantial changes. The primary objective of this study was to evaluate and characterize medical residents Ì satisfaction with medical residency programs in Portugal and to identify features that could be improved. MATERIAL AND METHODS: We utilized as model the survey Postgraduate Hospital Educational Environment Measure that has been developed in the United Kingdom and is speci cally targeted to medical residents. The survey was translated and adapted to the Portuguese reality. The survey was available online during April and May of 2016. RESULTS: A total of 3456 responses were obtained, corresponding to a response rate of 35%. Endocrinology/Nutrition, Cardiology, Anesthesiology, Family Physician and Gastroenterology were the specialties in which the degree of satisfaction was higher, while Forensic Medicine, Medical Oncology, Internal Medicine, General Surgery and Pneumology showed the lowest level of satisfaction. DISCUSSION: This study presented a high response rate when compared to previous studies. Portuguese medical residents presented high levels of satisfaction. Depending on year of medical residency, region, type of specialty and type of hospital marked asymmetries were noticed. CONCLUSION: The survey Ìs results should constitute in the future a support tool for the implementation of local and national measures relating to the medical residency. It is advisable to regularly conduct satisfaction surveys to medical residents.
Introdução: Nos últimos anos, o contexto global da formação médica, e em particular do Internato Médico em Portugal, sofreu profundas alterações. O presente estudo teve como objetivo avaliar e caracterizar a satisfação dos médicos internos com a realização do Internato Médico em Portugal e identificar aspetos passíveis de melhoria.Material e Métodos: Foi utilizado como modelo de inquérito o questionário Postgraduate Hospital Educational Environment Measuredesenvolvido no Reino Unido e dirigido a médicos internos, o qual foi traduzido e adaptado à realidade portuguesa. O questionário esteve disponível online durante os meses de abril e maio de 2016.Resultados: Foram obtidas 3456 respostas, correspondendo a uma taxa de resposta de 35%. Endocrinologia/Nutrição, Cardiologia, Anestesiologia, Medicina Geral e Familiar e Gastrenterologia foram as especialidades nas quais o grau de satisfação foi mais elevado,enquanto que Medicina Legal, Oncologia Médica, Medicina Interna, Cirurgia Geral e Pneumologia apresentaram o grau de satisfaçãomais baixo.Discussão: O presente estudo apresenta uma elevada taxa de resposta comparativamente com estudos prévios. A nível nacional, no global, os médicos internos apresentaram níveis elevados de satisfação, destacando-se marcadas assimetrias de acordo com o ano de especialidade, região, tipologia de instituição e de especialidade.Conclusão: Os resultados deste inquérito poderão constituir uma ferramenta de apoio à implementação de medidas de âmbito local enacional relacionadas com o Internato Médico, sendo desejável a realização regular de inquéritos de satisfação aos médico internos.
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Medicina Interna/educación , Internado y Residencia , Humanos , Satisfacción Personal , Portugal , Encuestas y CuestionariosRESUMEN
Different techniques of molecular biology have been used to screen for RET rearrangements. More recently, immunohistochemistry has been used, assuming that RET is not expressed in normal thyroid follicular cells. The present study was designed to define the prevalence of RET expression in patients with papillary thyroid carcinoma, by immunohistochemistry and by RT-PCR; to search specifically for RET/PTC-1; -2; -3 rearrangements using RT-PCR, and to compare results obtained by immunohistochemistry with those obtained by RT-PCR. Immunohistochemistry was performed using a polyclonal antibody against tyrosine kinase domain of Ret protein. Screening for RET/PTC1-3 was performed using RT-PCR and specific primers for each rearrangement; complementarily, a subset of cases were tested using RET exon 10/11 primers designed to detect the expression of the wild-type RET. Positive staining was observed in 30 of 39 (77%) tumours. RET/PTC1-3 rearrangements were detected in 8 of 32 (25%) cases. Ten of 15 (67%) cases expressed the wild-type RET. Two tumours characterised by positive immunostaining, absence of RET 5' expression and absence of RET/PTC1-3 expression were considered as expressing a RET rearrangement different from RET/PTC-1, -2, or -3. In 3 of 10 tumours, expression of the wild-type RET coexisted with the expression of a RET rearrangement. Positive staining does not necessarily mean the presence of a rearrangement; it may correspond to the expression of the wild-type RET, RET rearrangement or both. On the contrary, positive staining without evidence for the expression of the extracellular domain of RET is highly suggestive of a RET rearrangement independently of the type. Refinement of diagnosis depends on RT-PCR with specific primers.