Microcarcinoma papilar de tiroides: vigilancia activa. Revisión de la bibliografía / Papillary thyroid microcarcinoma: active surveillance. Literature review

El cáncer de tiroides ha aumentado en incidencia, sin embargo, la mortalidad se mantiene estable. Muchas de estas lesiones son a expensas de un microcarcinoma papilar de tiroides definido por la OMS como aquel carcinoma papilar de tiroides que en su diámetro máximo no sobrepasa los 10 mm. El avance de la imagenología sobre todo la ecografía de alta resolución y el hallazgo en pieza de anatomía patológica por lesiones benignas son las principales causas del aumento en el diagnóstico de esta entidad. La vigilancia activa surge entonces como alternativa de manejo para pacientes portadores de microcarcinoma papilar con bajo riesgo de progresión, obteniendo resultados oncológicos comparables. Independiente de su tratamiento el pronóstico de estos pacientes es excelente con sobrevida cercana al 100% en 10 años. A pesar de lo dicho la morbilidad de las distintas opciones terapéuticas es muy distinta. Será fundamental buscar elementos clínicos y paraclínicos que permitan tomar una decisión práctica, con el fin de determinar qué pacientes con microcarcinomas papilares que podrán entrar en un protocolo de vigilancia activa. Esta revisión pretende examinar la bibliografía publicada al respecto como alternativa de manejo, y su eventual aplicación en Uruguay.

Thyroid cancer has increased in incidence; however, mortality remains stable. Many of these lesions are at the expense of papillary thyroid microcarcinoma defined by the WHO as papillary thyroid carcinoma that in its maximum diameter does not exceed 10 mm. The advance of imaging, especially high-resolution ultrasound and the finding of benign lesions in pathological anatomy specimens are the main causes of the increase in the diagnosis of this entity. Active surveillance arises then as a management alternative for patients with papillary microcarcinoma with low risk of progression, obtaining comparable oncologic results. Regardless of their treatment, the prognosis of these patients is excellent with a survival rate close to 100% in 10 years. In spite of what has been said, the morbidity of the different therapeutic options is very different. It will be essential to look for clinical and paraclinical elements that will allow making a practical decision, in order to determine which patients with papillary microcarcinomas will be able to enter an active surveillance protocol. This review aims to examine the literature published on this subject as a management alternative, and its eventual application in Uruguay.

Efetividade da Alimentação na Prevenção do Câncer de Tireoide: Revisão Sistemática / Effectiveness of Food in Preventing Thyroid Cancer: Systematic Review / Eficacia de los Alimentos en la Prevención del Cáncer de Tiroides: Revisión Sistemática

Introdução: A glândula tireoide sofre alterações metabólicas que podem ocasionar doenças benignas ou malignas, sendo uma delas o câncer de tireoide, o qual está crescendo cada vez mais ao redor do mundo, sendo as mulheres mais propensas a desenvolver essa doença. Objetivo: Apresentar evidências científicas com base em revisão sistemática da literatura (PRISMA), verificando a efetividade da alimentação na prevenção do câncer de tireoide. Método: Para a seleção dos estudos, utilizou-se a combinação baseada no MedicalSubject Heading Terms (MeSH). Foram utilizadas as bases de dados MEDLINE (PubMed), LILACS, SciELO, BIREME e Scopus. O período de busca dos artigos compreendeu entre janeiro de 2010 até março de 2020, sem restrição de idioma e localização. Resultados:Foram recuperados 32 artigos com potencial de inclusão, sendo que três responderam à pergunta norteadora que consistiu em analisar qual a efetividade da alimentação na prevenção do câncer de tireoide. Conclusão: Os estudos relataram uma possível associação entre a ingestão de alimentos e a prevenção do câncer de tireoide. Sugere-se que os alimentos ricos em cálcio possam fornecer um papel protetor contra esse tipo de câncer, porém níveis excessivos de iodo na dieta também podem, de forma negativa, afetar a sua função da tireoide em razão das alterações nos seus níveis de hormônio. As pesquisas demonstram também que as mulheres apresentam significativamente maior incidência de câncer de tireoide em relação aos homens.

Introduction: The thyroid gland undergoes metabolic changes that can cause benign or malignant diseases, one of which is thyroid cancer, which is increasing worldwide, and women are most prone to develop this disease. Objective: To present scientific evidences based on a systematic review of the literature (PRISMA) verifying the effectiveness of food in preventing thyroid cancer. Method: For the selection of studies, the combination based in the Medical Subject Heading Terms (MeSH) was used. The MEDLINE (PubMed), LILACS, SciELO, BIREME and Scopus databases were utilized. The search period for the articles ranged from January 2010 to March 2020, with no language or localization restrictions. Results: 32 articles with potential for inclusion were retrieved, and three articles responded to the guiding question that consisted in analyzing the effectiveness of food in preventing thyroid cancer. Conclusion: Studies have reported a possible association between food intake and the prevention of thyroid cancer. It is suggested that food rich in calcium may play a protective role against thyroid cancer, but excessive levels of iodine in the diet may also affect thyroid function negatively due to changes in hormone levels. The researches also demonstrate that women have significantly higher incidence of thyroid cancer than men.

Introducción: La glándula tiroides sufre cambios metabólicos que pueden causar enfermedades benignas o malignas, una de las cuales es el cáncer de tiroides. Lo cáncer de tiroides está creciendo cada vez más en todo el mundo, siendo las mujeres las más propensas a desarrollar esta enfermedad. Objetivo: Presentar evidencia científica basada en una revisión sistemática de la literatura (PRISMA) que verifique la efectividad de los alimentos en la prevención del cáncer de tiroides. Método: Para la selección de los estudios, se utilizó la combinación basada en los términos de encabezado de temas médicos (MeSH). Se utilizaron las bases de datos MEDLINE (PubMed), LILACS, SciELO, BIREME y Scopus. El período de búsqueda de los artículos varió desde enero de 2010 hasta marzo de 2020, sin restricciones de idioma y localización. Resultados: Se recuperaron 32 artículos con potencial de inclusión, y tres artículos respondieron a la pregunta guía que consistió en analizar la efectividad de los alimentos para prevenir lo cáncer de tiroides. Conclusión: Los estudios han reportado una posible asociación entre la ingesta de alimentos y la prevención de cáncer de tiroides. Se sugiere que los alimentos ricos en calcio pueden proporcionar un papel protector contra lo cáncer de tiroides, pero los niveles excesivos de yodo en la dieta también pueden afectar negativamente la función tiroidea debido a los cambios en los niveles hormonales. La investigación también muestra que las mujeres tienen una incidencia significativamente mayor de cáncer de tiroides en comparación con los hombres.

Incidencia y mortalidad del cáncer de tiroides en Costa Rica 1990-2014 / Incidence and Mortality of Thyroid Cancer in Costa Rica, 1990-2014

Resumen Justificación y objetivo: determinar la incidencia y mortalidad del cáncer de tiroides en Costa Rica 1990-2014. Metodología: investigación descriptiva observacional de corte transversal. El estudio fue realizado en los costarricenses con diagnóstico (7 265 casos nuevos) y muerte (382 defunciones) de cáncer de tiroides, en el periodo 1990-2014. La información se obtuvo de las bases de datos del Centro Centroamericano de la Población, el Instituto Nacional de Estadística y Censo y el Registro Nacional de Tumores, usando los códigos de Clasificación Internacional de Enfermedades 9 y 10. Se hace el cálculo de tasas ajustadas por 100 000 habitantes, porcentajes y años de vida potencialmente perdidos. Resultados: la mortalidad por cáncer de tiroides en Costa Rica mostró una tendencia al ascenso leve durante el periodo de 1990 a 2014. Predomina en el sexo femenino, con una razón de 3:1 y afecta principalmente a la población mayor de 60 años, con tasas mayores en las provincias de Cartago, San José y Heredia. La incidencia, de igual manera, tuvo una tendencia al ascenso, en este caso moderada, al igual que se observó para los años de vida potencialmente perdidos. Conclusión: la mortalidad, la incidencia y los años de vida potencialmente perdidos por cáncer de tiroides en Costa Rica presentan tendencia al ascenso a lo largo del periodo de estudio.

Abstract Background and Aim : To determine the incidence and mortality of thyroid cancer in Costa Rica from 1990 to 2014. Methodology: descriptive cross-sectional observational research. The study was performed in Costa Ricans with diagnosis (7 265 new cases) and death (382 deaths) of thyroid cancer, in the period 1990-2014. The information was obtained from the databases of the Central American Population Center, the National Institute of Statistics and Census and the National Registry of Tumors, using the International Classification of Diseases 9 and 10. Calculation of adjusted rates by 100 000 inhabitants, percentages and years of life potentially lost was obtained. Results: mortality from thyroid cancer in Costa Rica showed a slight upward trend during the period from 1990 to 2014. It was predominant in females, with a ratio of 3: 1 and affected mainly the population over 60 years old, with higher rates in the provinces of Cartago, San José and Heredia. The incidence, in the same way, had a tendency to rise, moderately, just as it was observed for the years of life potentially lost. Conclusion: Mortality, incidence and years of life potentially lost due to thyroid cancer in Costa Rica present a tendency to rise throughout the study period.

Cirugía profiláctica en cáncer medular de tiroides hereditario / Prophylactic surgery in hereditary medullary thyroid cancer

Introducción: Se estima que del total de los cánceres, el 5-10% tendría una base genética. Actualmente es posible identificar a los individuos con predisposición genética en algunos cánceres como manera de intervenir precozmente en el desarrollo de esta enfermedad. Objetivos: Evaluar la utilidad de la cirugía profiláctica en el cáncer medular de tiroides hereditario. Material y métodos: Este trabajo es una revisión de literatura de diferentes estudios extraídos de bibliotecas electrónicas como Scientific Electronic Library Online (SciELO), MedLine-PubMed y UpToDate, mediante la construcción de preguntas clínicas y términos MeSH enfocados principalmente en la búsqueda específica de información sobre el cáncer medular de tiroides hereditario. Resultados: Los estudios revisados demuestran que la tiroidectomía profiláctica con resección linfática cervical representa el único tratamiento eficaz en el caso del cáncer medular de tiroides hereditario. Conclusiones: La cirugía profiláctica ha demostrado una importante disminución del riesgo de cáncer de tiroides y se considera una conducta de rigor en portadores del gen RET en el cáncer medular de tiroides.

Introduction: Approximately 5-10% of global cancer has a genetic base. Nowadays it is possible to identify those who have a genetic predisposition for some cancers, so they can be treated in short term. Objectives: Evaluate how useful is prophylactic surgery on hereditary Medullary Thyroid Cancer. Materials and methods: This investigation is a literature review of different research papers from electronic databases such as Scientific Electronic Library Online (SciELO), MedLine-PubMed and UpToDate. The research was made with clinical queries and MeSH terms, specially focused on hereditary Medullary Thyroid Cancer. Results: This research shows that prophylactic Thyroidectomy with cervical lymph node resection is the only effective and curative treatment for hereditary Medullary Thyroid Cancer. Conclusions: Prophylactic surgery has proof an important role decreasing the risk on Hereditary Thyroid cancer Syndrome and in RET carriers surgery is considered a must.

Seguimiento de pacientes con cáncer diferenciado de tiroides / Management of patients with differentiated thyroid carcinoma

El pronóstico del cáncer diferenciado de tiroides, excluida la variedad medular, es bueno, con una tasa de supervivencia a 10 años que excede el 90%.

Multiple endocrine neoplasia: the Chilean experience

Multiple endocrine neoplasia (MEN) types 1 and 2 are genetic diseases that are inherited as autosomal traits. The major clinical manifestations of multiple endocrine neoplasia type 1 include the so-called "3 P's": parathyroid, pituitary, and pancreatic tumors, including gastroenteroneuroendocrine tumors. Genetic testing can be performed on patients and the potential carriers of the menin gene mutation, but the genotype-phenotype correlation in multiple endocrine neoplasia type 1 is less straightforward than multiple endocrine neoplasia type 2. Most likely, the main advantage of genetic testing in MEN1 is to exclude from further studies those who are negative for the genetic mutation if they belong to a family with a known history of MEN1. In Chile, we started with rearranged during transfection proto-oncogene genetic testing (MEN2) 15 years ago. We carried out a prophylactic total thyroidectomy to prevent medullary thyroid carcinoma in a three-year-old girl who presented with microscopic medullary thyroid carcinoma. More than 90% of the individuals who tested positive using a genetic test achieved a biochemical cure compared with only 27% of patients who receive a clinical diagnosis. Mutations are mainly located in exon 11; the most common is C634W, rather than C634R. Hypertensive crisis was the cause of death in three patients, and extensive distant metastases occurred in nine (including two patients with multiple endocrine neoplasia type 2B) of 14 patients. Earlier recognition of medullary thyroid carcinoma and the other features of the disease, especially pheochromocytoma, will improve the survival rate of patients with multiple endocrine neoplasia.

Valor diagnóstico da tomografia por emissão de pósitrons / tomografia computadorizada (PET-CT) com flúor-18 fluordeoxiglicose (FDG-18F) em pacientes com carcinoma diferenciado da tireóide, níveis séricos de tireoglobulina elevados e pesquisa de corpo inteiro com iodo negativa / Diagnostic value of positron emission tomography / computed tomography with fluorine-18 fluordeoxyglucose in patients with differentiated thyroid gland carcinoma, high thyroglobulin serum levels and negative iodine whole body scan

OBJETIVO: Avaliar o papel da PET-CT com FDG-18F na detecção de recidiva e/ou metástase de carcinoma diferenciado da tireóide (CDT) em pacientes com níveis elevados de tireoglobulina (TG) e PCI negativa. PACIENTES E MÉTODO: Os achados da PET-CT de 25 pacientes foram comparados com a avaliação histopatológica e os métodos convencionais de imagem (MC). RESULTADOS: A PET-CT foi positiva em 16 pacientes com resultado verdadeiro-positivo em 14 e falso-positivo em 2 casos (valor preditivo positivo 87,5 por cento). Nove pacientes tiveram PET-CT negativa; dois evoluíram com níveis indetectáveis de TG. Doença residual foi observada na PCI pós-dose terapêutica de uma paciente. Seis pacientes não apresentaram evidências de tumor durante o seguimento (média 16 meses). PET-CT foi concordante com MC em 52 por cento, parcialmente concordante em 12 por cento e discordante (6 falso-negativos e 3 falso-positivos dos MC) em 36 por cento. Foi observada uma tendência de aumento da proporção de PET-CT positiva com o aumento de TG. CONCLUSÃO: A PET-CT com FDG-18F é útil na detecção de recidiva e/ou metástases de CDT com níveis de TG elevados mas PCI negativa. Apresenta alto valor preditivo positivo e é superior aos MC, sendo mais efetiva quanto maior o nível de TG.

PURPOSE: To evaluate the role of PET-CT with FDG-18F in the detection of recurrence and/or metastasis of differentiated thyroid carcinoma (DTC) in patients with elevated levels of thyroglobulin (TG) and negative whole body scan (WBS). PATIENTS AND METHOD: PET-CT findings of 25 patients were compared to histopathology evaluation and conventional imaging (CI). RESULTS: PET-CT scan was positive in 16 patients finding 14 true-positive and 2 false-positive cases (positive predictive value 87.5 percent). Nine patients had negative PET-CT; two had decrease of TG to undetectable levels. One patient had residual disease detected by post-therapeutic WBS. Six patients had no evidence of tumor during follow-up (mean time 16 months). PET-CT was concordant with CI in 52 percent, partially concordant in 12 percent and discordant in 36 percent (6 false-negatives and 3 false-positive of CI). We observed a tendency of increasing proportion of positive PET-CT with increasing TG. CONCLUSION: PET-CT scan with FDG-18F is useful in the detection of recurrence and/or metastases of DTC with high TG levels but negative WBS. It presents elevated positive predictive value and is superior to CI being more effective as higher the serum TG levels.

Tiroidectomía profiláctica en niños y jóvenes con cáncer medular tiroideo hereditario: Experiencia chilena / Prophylactic thyroidectomy in children and young people with hereditary medullary thyroid carcinoma: A Chilean experience

Background: With the availability of the RET proto-oncogene genetic testing, it is possible to perform prophylactic total thyroidectomy among carriers of RET mutation. Aim: To evaluate the histological findings and the effects of the prophylactic total thyroidectomy in first-degree relatives of Chilean patients with multiple endocrine neoplasia type 2 (MEN 2) based on the Ret proto-oncogen analysis. Subjects and Methods: Nineteen patients belonging to 11 MEN 2 families underwent total thyroidectomy. Of these, 16 either with C cell hyperplasia (CCH) or microscopic medullary thyroid carcinoma (MTC) were selected for the final analysis. Results: The age at the moment of thyroidectomy ranged from 3 to 24 years (median 9.5). The most common mutation was located in codon 634 (69%) followed by codon 620 (25%). Histopathology revealed MTC in 13 patients (81%, youngest 3 years, oldest ones 19 and 24 years) and CCH in 3. A significant correlation was observed between basal preoperative serum calcitonin/tumor size (r= 0.53, P <0.05) and age/tumor size (r= 0.56, P <0.03), but not between basal preoperative serum calcitonin and age. Stimulated preoperative calcitonin levels were confounding and not useful for differentiating CCH from MTC. None of patients in whom cervical dissection was done (9/16) presented lymph node metastases, including the oldest ones. All patients but the older ones were biochemically cured after a mean of 5 years of follow-up. Conclusion: Prophylactic total thyroidectomy should be done early in life because there is an age-dependent progression from HCC to MTC. MTC often precedes biochemical detection of the disease.