Risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy in thyroid nodules with diameters greater than 4 centimeters

ABSTRACT Objective: The risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy (FNAB) of thyroid nodules (TN) with diameters ≥ 3-4 cm remains controversial. However, some groups have indicated surgical treatment in these patients regardless of the FNAB results. We aimed to evaluate the diagnostic accuracy of the FNAB in systematically resected ≥4 cm TN and if the risk of malignancy is higher in these patients. Subjects and methods: We retrospectively evaluated 138 patients (142 nodules) with TN with diameters ≥4 cm who underwent thyroidectomy. Results: The FNAB results were nondiagnostic/unsatisfactory (ND/UNS) in 2.1% of the cases and benign in 51.4%. They indicated atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) in 23.9% of cases, follicular neoplasia/suspicious for a follicular neoplasm (FN/SFN) in 9.2%, suspicion of malignancy (SUS) in 8.5%, and malignant in 4.9%. The histopathological analysis after thyroidectomy revealed a thyroid cancer rate of 100% in the FNABs classified as malignant, 33.3% in SUS cases, 7.7% in FN/SFN, 17.6% in AUS/FLUS, and 4.1% in benign FNABs. None of the ND/UNS FNABs were malignant. The global malignancy diagnosis was 14.8% (n = 21). However, the rate of false negatives for FNAB was low (4.1%). Conclusion: We showed that the risk of malignancy in nodules with diameters ≥4 cm was higher compared to the risk of thyroid cancer in TN in general. However, we found a low rate of false-negative cytological results; therefore, our data do not justify the orientation of routine resection for these larger nodules.

Thyroid cancer burden and economic impact on the Brazilian public health system

ABSTRACT Objective: Recent data indicates an increasing incidence of thyroid cancer not accompanied by a proportional increase in mortality, suggesting overdiagnosis, which may represent a big public health problem, particularly where resources are scarce. This article aims to describe and evaluate the procedures related to investigation of thyroid nodules and treatment and follow-up of thyroid cancer and the costs for the Brazilian public health system between 2008 and 2015. Materials and methods: Data on procedures related to investigation of thyroid nodules and treatment/follow-up of thyroid cancer between 2008 and 2015 in Brazil were collected from the Department of Informatics of the Brazilian Unified Health System (Datasus) website. Results: A statistically significant increase in the use of procedures related to thyroid nodules investigation and thyroid cancer treatment and follow-up was observed in Brazil, though a reduction was noted for procedures related to the treatment of more aggressive thyroid cancer, such as total thyroidectomy with neck dissection and higher radioiodine activities such as 200 and 250 milicuries (mCi). The procedures related to thyroid nodules investigation costs increased by 91% for thyroid ultrasound (p = 0.0003) and 128% in thyroid nodule biopsy (p < 0.001). Costs related to treatment and follow-up related-procedures increased by 120%. Conclusion: The increase in the incidence of thyroid cancer in Brazil is directly associated with an increased use of diagnostic tools for thyroid nodules, which leads to an upsurge in thyroid cancer treatment and followup-related procedures. These data suggest that substantial resources are being used for diagnosis, treatment and follow-up of a potentially indolent condition.

Clinical utility of 18F-FDG PET/CT in the follow-up of a large cohort of patients with high-risk differentiated thyroid carcinoma

ABSTRACT Objective To evaluate the clinical utility of 18F-FDG PET/CT in patients with high-risk DTC. Subjects and methods Single-center retrospective study with 74 patients with high-risk differentiated thyroid cancer (DTC), classified in 4 groups. Group 1: patients with positive sTg or TgAb, subdivided in Group 1A: negative RxWBS and no foci of metastases identified at conventional image (n = 9); Group 1B: RxWBS not compatible with suspicious foci at conventional image or not proportional to sTg level (n = 13); Group 2: patients with histological findings of aggressive DTC variants (n = 21) and Group 3: patients with positive RxWBS (n = 31). Results 18F-FDG PET/CT identified undifferentiated lesions and helped restage the disease in groups 1B and 2. The scan helped guide clinical judgment in 9/13 (69%) patients of group 1B, 10/21 (48%) patients of group 2 and 2/31 (6%) patients of group 3. There was no clinical benefit associated with group 1A. 18F-FDG PET/CT was associated with progressive disease. Conclusion 18F-FDG PET/CT is a useful tool in the follow-up of patients with high-risk DTC, mainly in the group of RxWBS not compatible with suspicious foci at conventional image or not proportional to sTg level and in those with aggressive DTC variants. Additionally, this study showed that 18F-FDG PET/CT was associated with progression and helped display undifferentiated lesions guiding clinical assessments regarding surgeries or expectant treatments.

Clinical impact of thyroglobulin (Tg) and Tg autoantibody (TgAb) measurements in needle washouts of neck lymph node biopsies in the management of patients with papillary thyroid carcinoma

ABSTRACT Objectives The presence of thyroglobulin (Tg) in needle washouts of fine needle aspiration biopsy (Tg-FNAB) in neck lymph nodes (LNs) suspected of metastasis has become a cornerstone in the follow-up of patients with papillary thyroid carcinoma (PTC). However, there are limited data regarding the measurement of anti-Tg antibodies in these washouts (TgAb-FNAB), and it is not clear whether these antibodies interfere with the assessment of Tg-FNAB or whether there are other factors that would more consistently justify the finding of low Tg-FNAB in metastatic LNs. Materials and methods We investigated 232 FNAB samples obtained from suspicious neck LNs of 144 PTC patients. These samples were divided according to the patient’s serum TgAb status: sTgAb- (n = 203 samples) and sTgAb+ (n = 29). The TgAb-FNAB levels were measured using two different assays. Tg-FNAB was also measured using two assays when low levels (< 10 ng/mL) were identified in the first assay of the metastatic LNs from the sTgAb+ samples. Results The TgAb-FNAB results were negative in both assays in all samples. Low levels of Tg-FNAB were identified in 11/16 of the metastatic LNs of the sTgAb+ patients and 16/63 of the sTgAb- patients (p < 0.05) using assay 1. The measurement of the Tg-FNAB levels using assay 2 indicated additional metastases in 5 LNs of the sTgAb+ patients. Conclusions Factors other than the presence of TgAb-FNAB may contribute to the higher number of metastatic LNs with undetectable Tg-FNAB in the sTgAb+ group. In addition, the measurement of Tg-FNAB using different assays was useful to enhance the diagnosis of metastatic LNs, particularly when cytological and Tg-FNAB results are discordant.

Development, characterization and clinical validation of new sensitive immunofluorometric assay for the measurement of serum thyroglobulin / Desenvolvimento, caracterização e validação clínica de um novo ensaio sensível para a dosagem da tiroglobulina sérica

OBJECTIVE: In the last decade, data published stressed the role of highly-sensitive thyroglobulin (Tg) assays in the follow-up of differentiated thyroid carcinoma (DTC) patients. The present study describes a new, highly-sensitive Tg assay, compares it with an available commercial assay, and validates it in the follow-up of DTC patients. SUBJECTS AND METHODS: The immunofluorometric high-sensitivity Tg assay is based on monoclonal and polyclonal antibodies produced at our laboratories. It was validated in 100 samples of 87 patients with DTC submitted to total thyroidectomy, 87% of whom also received radioiodine. For correlation, all samples were also tested using a commercial Tg assay (Beckman Access) with functional sensitivity (FS) of 0.1 ng/mL. RESULTS: The new method showed FS of 0.3 ng/mL. The correlation between the two methods was good (r = 0.74; p < 0.0001). The diagnostic sensitivity was 88.9%, and it was increased to 100% when combined with neck US. CONCLUSION: This new, high-sensitivity Tg assay presented a good correlation with Beckman Access assay and with the clinical outcome of the patients. The continuous availability of a validated assay is an additional advantage for long term follow-up of DTC patients. Arq Bras Endocrinol Metab. 2012;56(9):658-65.

OBJETIVO: Na última década, estudos mostraram a importância dos ensaios de tiroglobulina (Tg) com melhor sensibilidade funcional no seguimento dos pacientes com carcinoma diferenciado de tiroide (CDT). Neste estudo, descrevemos o desenvolvimento de um novo ensaio de Tg de alta sensibilidade, que foi validado no seguimento de pacientes com CDT e correlacionado com um ensaio comercialmente disponível. SUJEITOS E MÉTODOS: O ensaio imunofluorométrico de Tg baseia-se em anticorpos, um monoclonal e um policlonal desenvolvidos em nosso laboratório. Avaliamos 100 amostras de soro de 87 pacientes com CDT submetidos à tiroidectomia total, sendo que 87% deles também receberam 131I. A Tg foi dosada também em ensaio comercial (Beckman Access). RESULTADOS: A correlação entre os dois métodos foi de 0,74 (p < 0,0001). O novo ensaio mostrou uma sensibilidade funcional de 0,3 ng/mL. A sensibilidade diagnóstica foi de 88,9%, que aumentou para 100% quando associada ao ultrassom cervical (US). CONCLUSÃO: O novo método de dosagem de Tg mostra boa correlação com o ensaio comercial Beckman Access e com a evolução clínica dos pacientes. O novo ensaio será fundamental no seguimento dos nossos pacientes com CDT. Arq Bras Endocrinol Metab. 2012;56(9):658-65.

Seven-year follow-up of a juvenile female with papillary thyroid carcinoma with poor outcome, BRAF mutation and loss of expression of iodine-metabolizing genes / Sete anos de seguimento de uma paciente jovem com carcinoma papílfero de tireóide e mutação de BRAF e perda de expressão de genes do metabolismo de iodo

BACKGROUND: Recent studies reported that BRAF V600E mutation, the most prevalent genetic event found in papillary thyroid carcinoma, is an independent poor prognostic marker. Additionally, it correlates with a less differentiated tumor stage due to reduced expression of key genes involved in iodine metabolism. We previously described a patient with BRAF V600E mutation in primary tumor and a new mutation (V600E+K601del) in the matched-lymph node metastases. In the present study we report an unusual clinical behavior of PTC and correlate with BRAF mutational status and level of expression of TSHR and NIS. METHODS: Quantitative PCR (qPCR) was used to evaluate the NIS and TSHR level of expression in matched papillary thyroid carcinoma and adjacent normal tissue. RESULTS: In this study, we presented a seven-year follow up of a juvenile papillary thyroid carcinoma patient who had an aggressive tumor harboring BRAF mutation, and failed to conventional therapy. We found a markedly decrease of NIS and TSHR expression in primary PTC compared to adjacent normal thyroid tissue. CONCLUSION: Our findings suggest that BRAF mutational status and decreased NIS and TSHR expression in this patient may reduce radioiodine uptake and lead to a negative response to radioiodine therapy.

INTRODUÇÃO: Estudos recentes demonstraram que a mutação V600E no gene BRAF é o evento genético mais freqüentemente encontrado em carcinoma papilífero da tiróide e um marcador de prognóstico independente. Adicionalmente, esta alteração genética tem sido correlacionada com a redução de expressão de genes envolvidos no metabolismo do iodo. Previamente, nosso grupo descreveu uma paciente com a mutação V600E no gene BRAF no tumor primário e uma mutação nova (V600E+K601del) em metástases pareadas. Neste estudo, reportamos um carcinoma papilífero com um comportamento clínico incomum e correlacionamos com a presença de mutação no gene BRAF e os níveis de expressão de TSHR e NIS. MÉTODO: Análise de expressão dos genes NIS e receptor de TSH (TSHR) através da técnica de PCR em tempo real. RESULTADOS: Descrevemos sete anos de acompanhamento de uma paciente jovem que apresentava um tumor com comportamento agressivo e baixa resposta aos tratamentos convencionais. Uma acentuada diminuição da expressão do TSHR e a ausência de expressão de NIS foram observadas no tumor primário desta paciente quando comparada com o tecido tiroidiano normal adjacente. CONCLUSÃO: Nossos dados sugerem que as mutações encontradas nesta paciente no gene BRAF com conseqüente perda de expressão dos genes NIS e TSHR podem ter reduzido a captação de iodo radioativo e a resposta ao tratamento.

Early diagnosis of multiple endocrine neoplasia type 2B: a challenge for physicians / Diagnóstico precoce de neoplasia endócrina múltipla tipo 2B: um desafio para os médicos

BACKGROUND: The hereditary form of medullary thyroid carcinoma may occur isolated as a familial medullary thyroid carcinoma (FMTC) or as part of Multiple Endocrine Neoplasia 2A (MEN2A) and 2B (MEN2B). MEN2B is a rare syndrome, its phenotype may usually, but not always, be noted by the physician. In the infant none of the MEN2B characteristics are present, except by early gastrointestinal dysfunction caused by intestinal neuromas. When available, genetic analysis confirms the diagnosis and guides pre-operative evaluation and extent of surgery. Here we report four cases of MEN2B in which the late diagnosis had a significant impact in clinical evolution and, potentially, in overall survival...

A forma hereditária do carcinoma medular da tiróide pode ocorrer de modo isolado, o carcinoma medular da tiróide familiar (FMTC), ou como parte das neoplasias endócrinas múltiplas tipo 2A (MEN2A) e 2B (MEN2B). MEN2B é uma síndrome rara e seu fenótipo é usualmente, mas nem sempre, notado pelo médico. Na infância, nenhuma das características de MEN2B estão presentes, exceto pela disfunção gastrintestinal precoce, causada pelos neuromas intestinais. Quando disponível, a análise genética confirma o diagnóstico e orienta a avaliação pré-operatória e extensão da cirurgia. Neste artigo, apresentamos quatro casos de MEN2B, nos quais o diagnóstico tardio teve impacto significativo na evolução clínica e, potencialmente, na mortalidade em geral...

Investigação de linfonodos em pacientes em seguimento por carcinoma diferenciado de tiróide / Cervical lymph nodes metastases in patients with differentiated thyroid cancer

Recorrências regionais dos carcinomas diferenciados de tiróide (CDT) são representadas por linfonodos cervicais em 60-75 por cento dos casos. Com a introdução da ultra-sonografia cervical (USC) no seguimento dos pacientes com carcinoma papilífero de tiróide (CPT) tornou-se freqüente o encontro de pequenos linfonodos (LNs) cervicais. Porém, apesar da USC apresentar alta sensibilidade, o estudo citológico obtido por punção aspirativa (PAAF), e nos últimos anos, a dosagem da tiroglobulina (Tg) no lavado da agulha da PAAF (Tg-PAAF), vêm assumindo papel importante no diagnóstico de LNs cervicais. O objetivo deste estudo é revisar a importância do diagnóstico precoce das metástases em linfonodos cervicais no seguimento dos pacientes com carcinoma de tiróide.

Loco-regional recurrences of the differentiated thyroid cancer have been reported to be located in cervical lymph nodes in 60-75 percent of cases. The widespread use of neck ultrasonography (US) during the follow-up of patients with papillary thyroid carcinoma (PTC) has led to the discovery of small cervical lymph nodes (LN). Although US has a high sensitivity for diagnosing LN, fine needle aspiration biopsy (FNA) and measurement of thyroglobulin in fine needle aspirates (FNA-Tg) have proven to be invaluable tools. The aim of this paper is to review the importance of the early diagnosis of lymph node metastases in the follow-up of patients with differentiated thyroid cancer.

Emprego da ultra-sonografia cervical no seguimento de pacientes com carcinoma diferenciado de tireóide / Usefulness of neck ultrasonography in the follow-up of patients with differentiated thyroid cancer

A ultra-sonografia (US) cervical é recomendada na avaliação de todos pacientes com carcinoma de tireóide após a terapia inicial, pois mesmo indivíduos de baixo risco com tireoglobulina (Tg) estimulada indetectável podem apresentar metástases cervicais. Para estas metástases, a US é o método mais sensível, superior à pesquisa de corpo inteiro (PCI) com 131I. Linfonodos cervicais com diâmetro > 5 mm com calcificações finas e/ou degeneração cística quase sempre são de etiologia maligna. Na ausência destas características, o formato arredondado e a ausência do hilo ecogênico são achados "suspeitos", enquanto linfonodos alongados e com hilo ecogênico visível são considerados benignos. A avaliação do fluxo, através do doppler, auxilia no diagnóstico diferencial, usualmente revelando hipervascularização periférica ou mista nos casos malignos. Na presença de linfonodos "suspeitos" na US, a avaliação citológica do material obtido através da punção aspirativa por agulha fina (PAAF) e a dosagem da Tg, obtida do lavado da agulha, são testes úteis e complementares para definir a etiologia, com elevada sensibilidade quando combinados e especificidade de 100 por cento. A US também é útil antes da tiroidectomia, auxiliando e até, em alguns casos, modificando o planejamento cirúrgico; e antes da ablação, para mensuração dos remanescentes tireoidianos e pesquisa de metástases linfonodais persistentes. Outra aplicação desse método de imagem é guiar a injeção de etanol (escleroterapia) ou a introdução de eletrodos para ablação com radiofreqüência em casos selecionados de metástases linfonodais isoladas, como alternativa às terapias convencionais.

Neck ultrasonography (US) is recommended for the assessment of all patients with thyroid carcinoma after initial therapy, since even low-risk patients with undetectable stimulated thyroglobulin (Tg) may present cervical metastases. In the case of these metastases, US is the most sensitive method and is superior to whole-body 131I scanning. Cervical lymph nodes with a diameter > 5 mm presenting thin calcifications and/or cystic degeneration have almost always a malignant etiology. In the absence of these characteristics, a round shape and the absence of an echogenic hilum are "suspicious" findings, whereas elongated lymph nodes with a visible echogenic hilum are considered benign. Doppler flow analysis helps with the differential diagnosis, usually revealing peripheral or mixed hypervascularization in malignant cases. In the presence of "suspicious" lymph nodes upon US, fine-needle aspiration cytology and measurement of Tg in the needle lavage fluid are useful and complementary exams for the definition of the etiology, with the combination of the two methods showing elevated sensitivity and 100 percent specificity. US is also useful before thyroidectomy, even contributing in some cases to modify the surgical planning, and before ablation for the measurement of thyroid remnants and detection of persistent lymph node metastases. Another application of this imaging method is to guide the injection of ethanol (sclerotherapy) or the introduction of electrodes for radiofrequency ablation in selected cases of isolated lymph node metastases as an alternative to traditional therapies.

Diagnóstico de metástases de carcinoma papilífero de tiróide através da dosagem de tiroglobulina no líquido obtido da lavagem da agulha utilizada na punção aspirativa / Diagnosis of metastases in patients with papillary thyroid cancer by the measurement of thyroglobulin in fine needle aspirate

Com a introdução da ultra-sonografia cervical (USC) no seguimento dos pacientes com carcinoma papilífero de tiróide (CPT), tornou-se freqüente o encontro de pequenos linfonodos (LNs) cervicais. Porém, apesar de a USC apresentar alta sensibilidade, o estudo citológico obtido por punção aspirativa (PAAF) e, nos últimos anos, a dosagem da tiroglobulina (Tg) no lavado da agulha da PAAF (Tg-PAAF) vêm assumindo papel importante no diagnóstico de LNs cervicais. O objetivo deste estudo é verificar a acurácia da combinação da USC, citologia e Tg-PAAF em LNs suspeitos. Estudamos 32 pacientes que apresentavam 44 LNs à USC, classificados como "inflamatórios" (19) ou "suspeitos" (25). Dos 25 LNs suspeitos, 15 apresentavam Tg-PAAF elevada (13 com citologia compatível com metástases e 2 com citologia não-diagnóstica). Esses 15 LNs (11 pacientes) foram confirmados como metástase de CP pelo exame histopatológico. Os 19 LNs "inflamatórios" e os 10/25 LNs "suspeitos" apresentaram citologia negativa e Tg-PAAF indetectável. Concluímos que a USC apresenta alta sensibilidade na detecção de linfonodos cervicais, porém citologia e dosagem de Tg-PAAF são fundamentais para o diagnóstico. A associação USC, citologia e Tg-PAAF pode ser considerada a abordagem mais sensível e específica na detecção de LNs metastáticos em pacientes com CPT.

The widespread use of neck ultrasonography (US) during the follow-up of patients with papillary thyroid carcinoma (PTC) has led to the discovery of small cervical lymph nodes (LN). Although US has a high sensitivity for diagnosing LN, fine needle aspiration biopsy (FNA) and measurement of thyroglobulin in fine needle aspirates (FNA-Tg) have proven to be invaluable tools. The aim of this study is to determine the sensitivity of the combined use of neck US, FNA biopsy and FNA-Tg for diagnosis of cervical lymph nodes. We have studied 32 patients with 44 LN detected by US, 19 classified as inflammatory and 25 as suspicious. 15 of those 25 suspicious LN had high FNA-Tg (13 of the 15 had positive cytology and 2 indeterminate). All of these 15 LN (11 patients) were proven to be PTC metastasis by histopathology. All 19 inflammatory LN and those 10/25 suspicious LN, had cytology negative for malignancy and undetectable FNA-Tg. We conclude that fine needle aspiration biopsy and FNA-Tg combined with neck US are essential for detecting positive cervical lymph nodes due to its high sensitivity and specificity and it should be considered the standard for investigating locally recurrent disease in patients with PTC.

Hipercalcemia associada a insuficiência adrenal aguda: relato de caso / Hypercalcemia associated to acute adrenal insuficiency: report of a case

A hipercalcemia associada a insuficiência adrenal aguda é fato conhecido, porém, a maioria dos relatos existentes na literatura se referem a casos isolados ou aparecem como dado complemetar em levantamentos de casuísticas clínicas de insuficiência adrenal. Relatamos o caso de uma paciente de 57 anos de idade, portadora de síndrome de Cushing consequente a adenoma de supra-renal, que após ressecçao cirúrgica e uso irregular de reposiçao glicocorticóide, evoluiu com queixas de astenia, anorexia, náuseas e vomitos. Ao exame físico mostrava-se desidratada, hipotensa e com descamaçao cutânea generalizada. Os exames laboratoriais mostraram eletrólitos normais, creatinina de 1,7 mg/dL (nl até cálcio 1,5), cálcio ionizado de 1,53 mmol/L (nl: 1, 14 - 1,29) e PTH intacto de 7 pg/mL (nl: 4 - 70), caracterizando portanto uma hipercalcemia nao dependente de PTH. Após receber hidrataçao venosa e hidrocortisona a paciente evoluiu com melhora da sintomatologia e normalizaçao dos parâmetros bioquímicos apresentando no 5( dia de internaçao, níveis de cálcio ionizado dentro da faixa normal. Os mecanismos fisiopatológicos que levam a este quadro metábolico sao múltiplos e poucos esclarecidos. Concluímos que a insuficiência adrenal aguda deve ser lembrada no diagnóstico diferencial de quadros de hipercalcemia.