Radiation exposure and thyroid cancer: a review

ABSTRACT The association between radiation exposure and the occurrence of thyroid cancer has been well documented, and the two main risk factors for the development of a thyroid cancer are the radiation dose delivered to the thyroid gland and the age at exposure. The risk increases after exposure to a mean dose of more than 0.05-0.1 Gy (50-100mGy). The risk is more important during childhood and decreases with increased age at exposure, being low in adults. After exposure, the minimum latency period before the appearance of thyroid cancers is 5 to 10 years. Papillary carcinoma (PTC) is the most frequent form of thyroid carcinoma diagnosed after radiation exposure, with a higher prevalence of the solid subtype in young children with a short latency period and of the classical subtype in cases with a longer latency period after exposure. Molecular alterations, including intra-chromosomal rearrangements, are frequently found. Among them, RET/PTC rearrangements are the most frequent. Current research is directed on the mechanism of genetic alterations induced by radiation and on a molecular signature that can identify the origin of thyroid carcinoma after a known or suspected exposure to radiation.

Além-Mar / Overseas

Nesta história, que se passa no litoral do Rio Grande do Norte, Antônio Lino conta a história de um médico ucraniano corajoso e generoso. Recém-formado, foi atender as vítimas de Chernobyl. Depois de alguns anos como refugiado na Europa, e de exercer várias profissões, volta a ser médico e atua naquele continente até que, movido por uma crise econômica e duas paixões, vem ao Brasil atuar no Programa Mais Médicos. O cotidiano de um médico da estratégia de saúde da família numa pequena comunidade é revelado com a profundidade e beleza com que Lino nos conta uma história. Como dito no prefácio do livro: "Lino nos oferece a história de um médico capaz de nos encher de admiração e carinho, produzindo identidade e referência também naqueles que são ou pretendem ser profissionais de saúde".

Tecnología nuclear: una historia de Catástrofes y progresos / Nuclear technology: a history of catastrophes and progresses

La presión científica alimentada por los diversos intereses geopolíticos de la primera mitad del siglo XX, fue sin duda el motor de impulso necesario para la investigación y el desarrollo de la tecnología nuclear. Una vez superada la crisis desencadenada por la Segunda Guerra Mundial, el conocimiento obtenido sobre los generadores atómicos aplicados a las necesidades civiles, no demoro en consolidar la energía nuclear como una opción futurista a la previsible escasez mundial de combustible. Es por eso, que el átomo se presento como una carta maestra para la seguridad, energía, economía, desarrollo y el cuidado ambiental. Sin embargo, pese a los controles para limitar su desarrollo como elemento militar, esta “panacea” no carece de generar dudas sobre su costo/beneficio. La historia relata algunos acontecimientos relacionados con dichos generadores, que han causado daños irreparables de manera inmediata y a largo plazo en el medio ambiente y en las poblaciones aledañas a aquellas estructuras. En el siguiente informe, se elabora una recopilación sobre el historial de eventos relacionados con el desarrollo de tecnología atómica, así como de la situación mundial de la energía nuclear...

Research and development of nuclear technology were done by a science under pressure of the geopolitical interests in the first half of the 20th century. Once the crisis triggered by the World War II passed, the knowledge gained about atomic generators applied to civilian needs, was able to quickly consolidate nuclear energy as a futuristic option for the global fuel shortage. At the same time, the atom was presented as a trump card for security, energetic, economic, and environmental development. However, despite the controls to limit its expansion as a military weapon, this “panacea” does not lack of doubts its costs versus its benefits. History can tell some events related to these generators, which have caused irreparable damage in their surrounding environment and nearby towns immediately and in a long term. In the following report, a review if the history of events related to the development of nuclear technology is made, as well as the overall situation of nuclear power worldwide...

Childhood thyroid cancer in Belarus, Russia, and Ukraine after Chernobyl and at present

Thyroid cancer in children is usually rare, but in the individuals exposed to radiation risk of disease increases considerably. After the Chernobyl accident in 1986, an over 10-fold maximal elevation in the incidence of thyroid cancer was registered about a decade later, cumulatively resulting in more than a thousand of newly diagnosed cases in children who lived in the territories of Belarus, Russia, and Ukraine affected by radioactive fallouts. Experience from the epidemic substantially promoted knowledge in clinical pediatric oncology, pathology and basic sciences. This article overviews epidemiology, clinical features, results of treatment and follow-up of childhood patients with radiation-induced Chernobyl thyroid cancer in comparison to sporadic cases diagnosed at present. In addition, we discuss general issues of pathology and molecular findings in childhood thyroid carcinomas.

O câncer de tiróide é habitualmente raro em crianças, mas em indivíduos expostos a radiação o risco da doença aumenta consideravelmente. Cerca de uma década após o acidente de Chernobil, em 1986, foi registrado um aumento de mais de 10 vezes na incidência de câncer de tiróide, resultando cumulativamente em mais de mil novos casos diagnosticados em crianças que viviam nos territórios da Bielorrússia, Russia, e Ucrânia, afetadas pela chuva radioativa. A experiência com essa epidemia resultou em conhecimento substancial de oncologia pediátrica clínica, patologia e ciências básicas. Este artigo analisa a epidemiologia, os achados clínicos, os resultados do tratamento e a evolução de pacientes pediátricos com câncer de tiróide induzido pela radiação de Chernobil, em comparação com casos esporádicos diagnosticados atualmente. Adicionalmente, serão discutidos tópicos de patologia e achados moleculares no carcinoma de tiróide infantil.