Lung metastases in patients with differentiated thyroid carcinoma and evaluation of response to radioiodine therapy

Introducción La localización más común de las metástasis a distancia en tumores diferenciados de tiroides es el pulmón. En este estudio se pretende determinar la proporción de metástasis pulmonares en el cáncer diferenciado de tiroides y su respuesta a la terapia con radioyodo. Material y métodos. Quinientos cuarenta y dos pacientes con cáncer diferenciado de tiroides fueron incluidos en este estudio. Se administraron altas dosis de 131I a los pacientes con metástasis pulmonares. La respuesta a la terapia se evaluó con estudios con 131I y niveles de tiroglobulina estimulada al menos 6 meses después de la terapia inicial. Resultados. Se detectaron metástasis pulmonares en 17 (3,1%) de los 542 pacientes. Tras la terapia con dosis altas de 131I se observó respuesta completa en 5 (29,4%), respuesta parcial en 3 (17,6%) y no se obtuvo respuesta en 9 (53%) de los pacientes. Conclusión. Aunque las metástasis pulmonares en los cánceres diferenciados de tiroides son raras, son más frecuentes en edades avanzadas y en varones. Altas dosis de 131I pueden ser beneficiosas, aunque habitualmente esta terapia debe repetirse(AU)

Introduction. The most common site of metastases in differentiated thyroid carcinomas is the lungs. In our study, we aimed to determine the ratios of lung metastases in patients with differentiated thyroid carcinoma and response to radioiodine therapy. Material and methods. A total of 542 patients with differentiated thyroid carcinoma who were admitted to our clinic were included in the study. High doses of 131I were administered to the patients with lung metastases. Response to therapy were evaluated with 131I scans and stimulated serum Tg levels were examined at least 6 months after therapy. Results. Lung metastases were detected in 17 (3.1%) of 542 patients with differentiated thyroid carcinoma. Of these patients to whom high doses of 131I therapy were administered, complete response to therapy was obtained in 5 (29.4%), partial response was obtained in 3 (17.6%) and no response could be obtained in 9 (53%) patients. Conclusion. Although lung metastases from differentiated thyroid carcinomas are rare, those are more common in advanced ages and in males. High doses of 131I therapy may be partially beneficial in these patients. Thus repetition of therapy is frequently required(AU)

Utilidad clínica de las pruebas hormonales e inmunológicas en la evaluación de las enfermedades del tiroides / Clinical usefulness of hormonal and immunological tests for the evaluation of thyroid diseases

Las enfermedades tiroideas son un importante problema de salud que afecta a un gran porcentaje de la población. Las pruebas bioquímicas constituyen el pilar fundamental para su diagnóstico y seguimiento. El desarrollo de ensayos de segunda y tercera generación ha supuesto un gran avance en el diagnóstico de estas enfermedades. El texto incluye los ensayos utilizados para diagnosticar y tratar las diferentes enfermedades tiroideas, provee información bioquímica y clínica actualizada contenida en secciones referidas a la utilidad clínica de las determinaciones de hormonas tiroideas totales y libres, anticuerpos antitiroideos, tirotropina humana y tiroglobulina, de manera que pueda ofrecer, tanto al laboratorio como al médico, un panorama general de la utilidad y la capacidad actual de estas pruebas(AU)

Thyroid diseases are a significant health problem affecting a high percentage of the population. The biochemical tests are the fundamental pillar for diagnosis and follow-up. The development of second and third-generation assays has represented a great advance in diagnosing these diseases. The text covers the tests to diagnose and treat a number of thyroid diseases, and provides the reader with updated biochemical and clinical information in sections about the clinical usefulness of total and free thyroid hormone determinations, antithyroid antibodies, human thyrotropin and thyroglobulin. In this way, it can offer both the lab and the physician a general overview of the usefulness and the current capability of these tests(AU)

Captación patológica de I-131 en pulmón en paciente con cáncer de tiroides: ¿metástasis o no? / Abnormal uptake of l-131 in the lung in a patient with thyroid cancer: Is it metastasis or not?

Mujer de 66 años con antecedentes de bronquiectasias quísticas en pulmón derecho en su infancia, que es remitida a consultas de Endocrinología para estudio de bocio multinodular. La paciente no refería antecedentes personales ni familiares de carcinoma de tiroides. En analítica realizada presenta las siguientes determinaciones hormonales: T4 libre 1,14μg/dl (LN: 0,9-1,7) y TSH 2,45μU/ml (LN 0,3-4,5). La ecografía mostraba varios nódulos en lóbulo tiroideo izquierdo menores de 1cm, hipoecogénicos y bien definidos, y uno mayor en lóbulo tiroideo derecho de 1,5cm, hipoecogénico, con aumento de vascularización central, microcalcificaciones y ausencia de halo. Se realizó punción-aspiración con aguja fina (PAAF) de este nódulo guiada por ecografía, y el resultado de la punción fue sospechoso de malignidad, motivo por el cual se decidió tratamiento quirúrgico mediante tiroidectomía total. El estadificación inicial según la American Joint Committee on Cancer (AJCC) fue pT1NxM0. El informe anatomo-patológico reveló varios focos de microcarcinoma folicular y papilar de 0,1 a 0,4cm en ambos lóbulos tiroideos. La paciente fue tratada con levotiroxina oral a dosis supresoras para evitar crecimiento tumoral. Cuatro meses después de la intervención recibió una dosis ablativa de yodo radiactivo (debido a la multifocalidad del tumor y al desconocimiento sobre la afectación ganglionar). Un año más tarde se realizó ecografía tiroidea que no mostró imágenes sospechosas de malignidad, así como niveles de Tg tras TSHr (que resultaron indetectables) y un rastreo corporal total diagnóstico con TSHr donde se evidenció un depósito patológico del radiotrazador en pulmón derecho de características heterogéneas y que sugerían la posibilidad de metástasis. ¿Cómo debe ser evaluada y tratada esta enferma?(AU)

A 66-year old woman with a background of cystic bronchiectasis in the right lung in her childhood was referred to Endocrinology for a study of multinodular goiter. The patient did not report any personal or family backgrounds of thyroid cancer. The analysis showed the following hormone levels: Free T4 1.14μg/dl (LN: 0.9-1.7) and TSH 2.45μU/ml (LN 0.3-4.5). The ultrasound showed several left thyroid lobe nodes smaller than 1cm, hypoechogenic and well-defined and a larger one in the right thyroid lobe of 1.5cm, hypoechogenic, with increase of central vascularization, microcalcifications and absence of halo. Ultrasound-guided fine needle aspiration puncture (FNAP) was performed on this node. The result of the puncture was suspicion of malignancy, which is why it was decided to perform surgical treatment by total thyroidectomy. Initial staging according to the American Joint Committee on Cancer (AJCC) was pT1NxM0. The pathology report revealed several foci of follicular and papillary microcarcinoma of 0.1 to 0.4cm in both thyroid lobes. The patient was treated with suppressive doses of oral levothyroxine to avoid tumor growth. Four months after the surgery, she received an ablative dose of radioactive iodine (due to the multifocality of the tumor and the lack of knowledge on the lymph node involvement). One year later, a thyroid ultrasound was performed that did not show suspicious images of malignancy. Levels of Tg after TSHr (that were undetectable) and a total diagnostic body scan with TSHr were performed. These showed an abnormal deposit of the radiotracer in the right lung having heterogeneous characteristics that suggested the possibility of metastases. How should this patient be evaluated and treated?(AU)

Cisto hepático benigno simulando metástase de carcinoma diferenciado de tireoide / Benign hepatic cyst mimicking thyroid carcinoma metastasis

INTRODUÇÃO: Pesquisa de corpo inteiro após dose terapêutica de (131I) NaI (PCI) associada à tireoglobulina (Tg) sérica, anticorpo antitireoglobulina (anti-Tg) e ultrassom (US) cervical representam os métodos de referência para detecção de carcinoma diferenciado de tireoide (CDT) residual ou metastático. Algumas causas de PCI falsos-positivas, como processos inflamatórios, alguns tumores não tireoidianos e até mesmo cistos renais e sebáceos, são bem conhecidas. MÉTODOS: Neste trabalho, descreveu-se um caso de cisto hepático benigno simulando metástase de carcinoma de tireoide em PCI após dose terapêutica de (131I) NaI. RESULTADOS: Ressalta-se a importância do reconhecimento dos cistos hepáticos benignos como fator complicador do seguimento dos pacientes com câncer de tireoide. CONCLUSÕES: Para minimizar erros de diagnóstico e, consequentemente, na condução dos casos de CDT, é necessário conhecer as possíveis causas de PCI falsos-negativas e positivas.

INTRODUCTION: The follow-up of differentiated thyroid carcinoma (DTC) for detecting persistent or recurrent disease is based on iodine whole body scan (WBS), the evaluation of the tumor marker thyroglobulin (Tg), the anti-thyroglobulin antibody (anti-Tg) and neck ultrasonography (US). Well known false-positive causes of WBS include inflammatory processes, some non-thyroid tumors, kidney or even sebaceous cysts . METHODS: We reported a case of false-positive WBS, after therapeutic dose of (131I) NaI. RESULTS: We enphasize the importance of recognizing benign liver cysts mimicking DTC metastasis. CONCLUSIONS: False-positive and negative results may occur with WBS and must be recognized to avoid mismanagement.

O ensaio de tiroglobulina com melhor sensibilidade funcional enquanto os pacientes tomam L-T4 substituirá a tiroglobulina estimulada pelo TSH no seguimento dos pacientes com câncer diferenciado da tiróide? / Will the thyroglobulin assay with lower functional sensitivity whilst the patients are on L-T4 treatment replace the TSH-stimulated thyroglobulin assay in the follow-up of patients with differentiated thyroid cancer?

O autor apresenta evidências recentes da literatura que mostram que ensaios de tiroglobulina sérica (sTg) com maior sensibilidade funcional apresentam a mesma qualidade que a obtenção da sTg estimulada por rhTSH ou hipotiroidismo, no seguimento de pacientes com câncer diferenciado de tiróide (CDT). Desta forma, propõe modificar a prática recomendada pelas diretrizes de sociedades internacionais para o seguimento desses pacientes (desenvolvidas enquanto os ensaios disponíveis apresentavam sensibilidade de 1 ng/mL), substituindo-se a obtenção da sTg estimulada por rhTSH ou hipotiroidismo pelo acompanhamento dos pacientes na vigência da terapia com L-T4 com a medida da sTg desde que se empreguem técnicas com sensibilidade funcional da ordem de 0,1-0,2 ng/mL.

The author reviews the literature on the new assays for serum thyroglobulin (sTg) presenting lower functional sensitivity and demonstrates that its use, whilst the patients are taking L-T4, presents better results than sTg following TSH stimulation in the follow-up of patients with differentiated thyroid carcinoma. Therefore, he suggests a revision on the guidelines for the follow-up of these patients (developed when the available assays present a sensitivity of 1 ng/mL), proposing the use of sTg assays with functional sensitivity of 0.1-0.2 ng/mL with the patients on L-T4 treatment instead of sTg stimulated by TSH.

Diagnóstico de metástase de carcinoma papilífero de tiróide através da pesquisa do RNA mensageiro da tiroglobulina / Diagnsotic of thyroid pappilary carcinoma metastasis by research of messenger RNA of thyroglobulin

É descrito um caso de carcinoma papilífero de tiróide pesquisado pelo RNA mensageiro da tiroglobulina (mRNA-Tg). A importância do método do mRNA-Tg no seguimento de pacientes com carcinoma diferenciado de tiróide em reposição tiroidiana é analisado.