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Advisor(s)
Abstract(s)
O carcinoma medular da tiroide, definido em 1959 por Hazard e Hawk, como um
tumor sólido com presença de amiloide, distinto de tumores papilares, corresponde a 1-2%
dos carcinomas da tiroide e pode ocorrer de duas formas, esporádica e hereditária. A forma
esporádica é a mais frequente, contando com aproximadamente 75% dos casos e uma
reduzida predominância no sexo feminino, contrariamente à forma hereditária que não
apresenta predominância de sexo. O carcinoma pode aparecer em qualquer faixa etária,
porém a forma esporádica apresenta predominância na 5ª década, enquanto na forma
hereditária o pico é na 2ª e 3ª década.
O carcinoma medular da tiroide hereditário é transmitido de modo autossómico
dominante, com uma penetrância aproximada a 100%. Assim como na forma esporádica, é
uma patologia maioritariamente provocada por uma mutação no gene RET, contudo ocorre
simultaneamente com outras neoplasias endócrinas como parte da síndrome neoplasias
endócrinas múltiplas, ou de forma isolada, sendo designado como carcinoma medular da
tiroide familiar.
O diagnóstico precoce é fundamental. Porém, no passado era apenas possível aquando
da presença de sintomas, espelhando uma doença avançada, enquanto atualmente a
realização de punção aspirativa por agulha fina, doseamento sérico de marcadores e
genotipagem permitem uma prematuridade no diagnóstico e abordagem posterior muito mais
individualizada.
A relação genótipo-fenótipo está estabelecida, permitindo identificar o risco de
doença através da mutação, possibilitando a abordagem personalizada caso a caso. O
diagnóstico e categorização de risco permitem atualmente um tratamento precoce, sendo de
notar que nos casos hereditários, a cirurgia profilática permite uma taxa de sobrevida
idêntica à população geral. Nos casos avançados, apenas a targeted therapy tem tido sucesso,
já com dois fármacos aprovados, mas sem nunca alcançarem a remissão completa.
Métodos: Pesquisa de artigos científicos, guidelines e consensos das bases PubMed,
Scielo e Google Scholar.
The medullary thyroid carcinoma, defined in 1959 by Hazard and Hawk as a solid tumor with presence of amyloid, distinct from papillary tumors, represents 1-2% of all thyroid carcinomas and can occur in two forms, sporadic and hereditary. The sporadic form is the most frequent, accounting for approximately 75% of all cases, while also displaying a slight female predominance, contrary to the hereditary form which doesn’t present predominance of either sex. The carcinoma can appear at any age; however, the sporadic form occurs predominantly in the fifth decade and the hereditary form in the second and third decade. Hereditary medullary thyroid carcinoma is transmitted through a dominant autosomal pattern, with a penetrance of almost 100%. As in the sporadic form, it is mainly caused by a mutation in the RET gene and develops alongside other endocrine neoplasia as a part of the multiple endocrine neoplasia syndrome, or isolated, being designated as familial medullary thyroid carcinoma. An early diagnosis is essential. In the past, this was only possible at onset of symptoms, which typically meant an advanced stage of the disease. However, recently developed techniques such as fine-needle aspiration, the dosing of markers and genotyping, have allowed a faster diagnosis as well as a much more specialized approach and follow-up. The genotype-phenotype relation is well established, allowing the identification of the disease’s risk through the present mutation. Diagnosis and risk categorization currently allow a timely treatment. To be noted that in the hereditary cases prophylactic surgery grants a survival rate identical to that of the general population. In more advance cases, only targeted therapy has been successful, with two drugs already having been approved for treatment. Complete remission however, has not yet been achieved. Methods: Research of cientific articles, guidelines and consensos from PubMed, Scielo and Google Scholar.
The medullary thyroid carcinoma, defined in 1959 by Hazard and Hawk as a solid tumor with presence of amyloid, distinct from papillary tumors, represents 1-2% of all thyroid carcinomas and can occur in two forms, sporadic and hereditary. The sporadic form is the most frequent, accounting for approximately 75% of all cases, while also displaying a slight female predominance, contrary to the hereditary form which doesn’t present predominance of either sex. The carcinoma can appear at any age; however, the sporadic form occurs predominantly in the fifth decade and the hereditary form in the second and third decade. Hereditary medullary thyroid carcinoma is transmitted through a dominant autosomal pattern, with a penetrance of almost 100%. As in the sporadic form, it is mainly caused by a mutation in the RET gene and develops alongside other endocrine neoplasia as a part of the multiple endocrine neoplasia syndrome, or isolated, being designated as familial medullary thyroid carcinoma. An early diagnosis is essential. In the past, this was only possible at onset of symptoms, which typically meant an advanced stage of the disease. However, recently developed techniques such as fine-needle aspiration, the dosing of markers and genotyping, have allowed a faster diagnosis as well as a much more specialized approach and follow-up. The genotype-phenotype relation is well established, allowing the identification of the disease’s risk through the present mutation. Diagnosis and risk categorization currently allow a timely treatment. To be noted that in the hereditary cases prophylactic surgery grants a survival rate identical to that of the general population. In more advance cases, only targeted therapy has been successful, with two drugs already having been approved for treatment. Complete remission however, has not yet been achieved. Methods: Research of cientific articles, guidelines and consensos from PubMed, Scielo and Google Scholar.
Description
Keywords
Calcitonina Carcinoma Medular da Tiroide Cmtf Inibidores da Tirosina Cinase Men2a Men2b