Subclinical Hypothyroidism with TSH>7 mIU/l and≤10 mIU/l and Coronary Artery Disease.

The association of subclinical hypothyroidism (SCH) with increased cardiovascular risk is controversial when thyroid-stimulating hormone (TSH) concentration is<10 mIU/l, as well as its association with a higher coronary artery calcium score (CACS) in individuals with low cardiovascular risk. This study evaluated coronary artery disease (CAD) by CACS in asymptomatic, low-cardiovascular risk women with SCH and TSH>7 mIU/l and≤10 mIU/l untreated for 5 years after diagnosis. The CACS was obtained for two groups of women with low cardiovascular risk. Group A consisted of 32 women with mild SCH (TSH>7 mIU/l and≤10 mIU/l) who remained untreated for 5 years, and group B consisted of 32 euthyroid women matched for age and body mass index to group A. The CACS ranged from 0 to 350 (median 0, 25-75% interval: 0-10) in group A and from 0 to 280 (median 0, 25-75% interval: 0-0) in group B. Scores>0 and≥10 were significantly more frequent in group A (40.6 vs. 12.5% and 25 vs. 3.1%, respectively). A CACS≥100 was also more frequent in group A (18.75 vs. 3.1%), but the difference was not significant (p=0.1). The results of the study suggest that long-term SCH with TSH>7 mIU/l and ≤ 10 mIU/l is associated with a higher risk of CAD in individuals≤65 years, even in those with low cardiovascular risk.

Are Papillary Thyroid Carcinomas That Are Candidates for Active Surveillance in Fact Classical Microcarcinomas Restricted to the Gland?

BACKGROUND: Patients with small papillary thyroid carcinomas (PTC) can currently be maintained under active surveillance (AS). The recommended criteria are the following: adult individual, tumor ≤1 cm and not adjacent to the trachea or recurrent laryngeal nerve, cytology non-suggestive of the aggressive subtype, absence of lymph node (LN) involvement and extrathyroidal extension (ETE) on ultrasonography (US), and absence of clinical distant metastases. This study aimed to evaluate the frequency of the following peri- and postoperative findings in patients who met the criteria for PTC being candidate for AS: tumor > 1 cm, aggressive subtype or vascular invasion, ETE, clinical LN metastases (cN1), and distant metastases. METHODS: We reviewed the results of peri- and postoperative evaluation and histology of patients with a preoperative diagnosis of PTC who would currently be candidates for AS. RESULTS: There were 124 patients (102 women) with nodules ≤1 cm (range 4-10 mm). All nodules corresponded to papillary microcarcinomas on histology and none of them were > 1 cm. Only one microcarcinoma (0.8%) was of the tall-cell subtype. Vascular invasion was found in 10 microcarcinomas (8%). None of the microcarcinomas were staged as T3b or T4, although microscopic ETE was observed in 25 tumors (20%). In 8 patients (6.4%), central LN involvement was suspected during perioperative evaluation and was confirmed by histology (cN1a). None of the patients had distant metastases (M0). CONCLUSION: Findings that define an intermediate risk of recurrence and favor total thyroidectomy were observed in 31.5% of patients with PTC who are candidates for AS.

Hipotireoidismo e doença auto-imune tireoidiana em diabéticos Tipo 2 / Hypothyroidism and autoimmune thyroid disease in Type 2 diabetic patients

Introdução: este estudo avaliou a prevalência de doença tireoidiana auto-imune e hipotireoidismo em diabéticos tipo 2 sem fatores de risco ou tireoidopatia aparente. Métodos: Foram selecionados 230 pacientes consecutivos diabéticos tipo 2. Destes, foram excluídos 111 pacientes que já apresentavam fatores de risco para disfunção tireoidiana. Os 119 pacientes restantes tinham exame clínico normal e foram investigados com dosagens de TSH, T4 livre e antiTPO. O grupo-controle foi constituído de 80 pacientes não diabéticos, semelhantes em relação a sexo e idade. Gestantes foram excluídas. Resultados: AntiTPO foi positivo em 10 (8,4 por cento) e TSH>5 mU1/1 em 11 (9,2 por cento) dos 119 diabéticos tipo 2; e hipotireoidismo franco foi demonstrado em quatro (3,3 por cento). No grupo-controle, antiTPO foi positivo em seis (7,5 por cento) e TSH>5mU1/1 em sete pacientes (8,7 por cento). Hipotireoidismo franco encontrado em dois (2,5 por cento). Conclusão: diabéticos tipo 2 sem fatores de risco conhecidos não apresentaram maior prevalência de doença auto-imune ou disfunção tireoidiana.

Carcinoma medular de tireóide: abordagem para prática clínica / Medullary thyroid carcinoma: na approach to clinical practice

O carcinoma medular da tireóide (CMT) representa 5 por cento dos tumores malignos dessa glândula e aproximadamente 25 por cento são hereditários, estes associados a mutações no proto-oncogene RET e ocasionalmente a outras neoplasias endócrinas (feocromocitona hiperparatireoidismo). O rastreamento familiar seguido da tireoidectomia naqueles com mutação no RET evita o aparecimento da doença em muitos indivíduos. O CMT esporático geralmente se apresenta como nódulo palpável ou já com sintomas de extensão extratireoidiana. Hipercalcitoninemia ocorre invariavelmente na doença clinicamente aparente. Recomenda-se tireoidectomia total com ressecção bilateral de lifonodos como tratamento inicial e, ocasionalmente, radioterapia, mas não (131) como terapia adjuvante. O seguimento é feito com as dosagens de CT e CEA, com realização de métodos de imagens nos pacientes com marcadores elevados. Presença de metástases linfonodais extensas e invasão extratireoidiana são fatores associados à menor chance de cura bioquímica (CT indetectável). Quando esta é alcançada, a sobrevida livre de doença em longo prazo é de 95 por cento.

Marcadores de remodelação e densidade mineral óssea em pacientes com deficiência de calcitonina / Markers of bone remodeling and bone mineral density in patients with calcitonin deficiency

Objetivo: Este estudo avaliou marcadores de remodelação e densidade mineral óssea (DMO) em mulheres pré-menopausadas com deficiência de calcitonina. Metodologia (pacientes e métodos): Um total de 12 pacientes tireoidectomizadas por doença benigna, mantidas em terapia de reposição com levotiroxina e com calcitonina sérica indetectável foram comparadas a 15 pacientes controles (semelhantes em relação a: idade, IMC, níveis de TSH). Elas não apresentavam co-morbidades associadas. Resultados: Cálcio, PTH e 1,25 (OH)2 vitamina D não diferenciaram nos dois grupos. Houve tendência a mais baixos valores séricos de fosfatase alcalina óssea e osteocalcina naquelas com deficiência de calcitonina e o N-telopeptídeo urinário foi significativamente mais alto neste grupo. A densidade mineral óssea foi significativamente mais baixa nas pacientes tireoidectomizadas, tanto em coluna lombar quanto em colo de fêmur. Conclusão: A deficiéncia de calcitonina pode estar associada a aumento da reabsorção óssea e redução da DMO em mulheres antes da menopausa.

Ultrasonographic differentiation between metastatic and benign lymph nodes in patients with papillary thyroid carcinoma.

OBJECTIVE: The purpose of this study was to evaluate the ultrasonographic characteristics of metastatic lymph nodes in patients with papillary thyroid carcinoma. METHODS: The ultrasonographic characteristics of lymph nodes were analyzed in 112 consecutive patients who underwent thyroidectomy and lymph node dissection, with the diagnosis being confirmed by anatomopathologic examination. RESULTS: A total of 198 lymph nodes were metastatic, and 152 were benign (normal or with nonspecific lymphadenitis). Minimum axial diameters of 7 mm for level II (upper internal jugular chain) and 6 mm for the rest of the neck were observed in 93% of metastatic lymph nodes, absence of an echogenic hilum in 88%, hyperechogenicity in relation to the adjacent muscles in 86%, a round shape in 80%, calcifications in 49.5%, and intranodal cystic necrosis in 20%. These ultrasonographic characteristics were observed in 17%, 10%, 4.5%, 29.5%, 0%, and 0% of benign lymph nodes, respectively. CONCLUSIONS: Even basic ultrasonographic characteristics (shape, echogenicity and echogenic hilum, calcifications, and intranodal cystic necrosis) help in the differentiation between metastatic and nonmetastatic lymph nodes in patients with papillary thyroid carcinoma.

Valor da varredura com iodo antes da terapia ablativa em pacientes com carcinoma de tireóide / Usefulness of iodine scanning before ablative therapy in patients with thyroid carcinoma

OBJETIVO: Avaliar a relevância clínica da varredura pré-dose ablativa em pacientes com carcinoma diferenciado de tireóide. MATERIAIS E MÉTODOS: Analisamos a varredura com 131I e a tireoglobulina (Tg) sérica em hipotireoidismo antes da primeira terapia ablativa em 100 pacientes submetidos a tireoidectomia total, considerando a varredura clinicamente importante quando revelou metástases ressecáveis ou que foram tratadas com doses maiores que a inicialmente proposta (100 mCi de 131I), além dos casos sem captação e com Tg < 5 ng/ml, que não receberam radioiodoterapia. RESULTADOS: A varredura revelou captação correspondente a metástases linfonodais em dez pacientes (10 por cento), metástases distantes em cinco (5 por cento), apenas em leito tireoidiano em 76 (76 por cento) e foi negativa em nove (9 por cento), sendo clinicamente relevante (indicando cirurgia, aumento da dose ou dispensando a radioiodoterapia) em 18 por cento dos pacientes. Nos pacientes com Tg > 10 ng/ml a varredura influenciou a conduta em 41 por cento dos casos pela presença de metástases, e naqueles com Tg < 10 ng/ml em apenas 10 por cento, na maioria por não receberem radioiodo. CONCLUSÃO: A varredura pré-dose ablativa fornece informacões clinicamente importantes (presença de metástases) em muitos pacientes com Tg > 10 ng/ml, sendo indicada nesta condição.

Thyroglobulin before ablation and correlation with posttreatment scanning.

OBJECTIVES/HYPOTHESIS: To determine the usefulness of thyroglobulin (Tg) before ablation and the correlation with posttreatment scanning in patients with thyroid carcinoma. STUDY DESIGN: Prospective. METHODS: Tg during hypothyroidism was determined in 212 patients after thyroidectomy and before ablation. The disease stage was based on clinical examination, Tg, posttherapy scanning, other imaging methods, and histologic confirmation in selected cases. RESULTS: One hundred sixty-four patients presented thyroid remnants only, 31 had lymph node metastases, and 17 had distant metastases. Posttreatment scanning showed a sensitivity of 71% for lymph node and of 94.1% for distant metastases. Ectopic uptake was observed in 5.6% of patients with Tg less than 1 ng/mL, in 9% with levels from 1 to 5 ng/mL, in 10.7% with Tg from 5 to 10 ng/mL, and in 51% with Tg greater than 10 ng/mL. The sensitivity of Tg for metastases was 73 and 66.5% and specificity was 73 and 88.4% at a cut-off value of 5 and 10 ng/mL, respectively. CONCLUSIONS: Postoperative Tg less than 10 ng/mL rarely show distant metastases and because these metastases were observed in 31% of patients with values greater than 10 ng/mL, this criterion can be selected for the indication of imaging methods, in addition to neck ultrasound (US). For cases with Tg less than 10 ng/mL, US is necessary because even patients with undetectable Tg had lymph node metastases. The same cut-off can be used for the indication of radioiodine therapy even in the absence of any evidence of disease because 51% of the patients with Tg greater than 10 ng/mL showed ectopic uptake on posttreatment scanning.

Is stimulation of thyroglobulin (Tg) useful in low-risk patients with thyroid carcinoma and undetectable Tg on thyroxin and negative neck ultrasound?

OBJECTIVE: To determine the usefulness of thyroglobulin (Tg) stimulation in low-risk patients with undetectable Tg on T4 and negative neck ultrasound (US) after initial therapy of thyroid carcinoma. METHODS: We evaluated 122 consecutive patients classified as low risk 6 months to 1 year after total thyroidectomy and remnant ablation. All patients had a normal clinical exam, Tg < or = 1 ng/ml during suppressive therapy (TSH < 0.1 mIU/l), and undetectable antithyroglobulin antibodies. RESULTS: After T4 withdrawal and elevation of TSH to values > 30 mIU/l, 26 patients (21.3%) converted Tg to levels > 1 ng/ml. Metastases were detected in 10 patients, nine showing stimulated Tg levels > 1 ng/ml. Cervical metastases were observed in 9/10 patients and lung metastases in one patient. Neck US identified all cervical metastases. Seventeen patients with stimulated Tg levels > 1 ng/ml initially showed no apparent disease, with a reduction in Tg being observed upon subsequent measurements, and 13 patients presented undetectable Tg off T4 at the end of the study. Undetectable Tg on T4 showed a high negative predictive value (NPV; 91.8%), which increased to 99.1% when combined with neck US. Stimulated Tg levels < 1 ng/ml presented a 98.9% NPV. A total of 113 patients with undetectable Tg on T4 and negative US had to be exposed to hypothyroidism in order to diagnose one further case of metastases. CONCLUSION: Undetectable Tg on T4 combined with negative neck US presented a high NPV in low-risk patients and Tg stimulation might be avoided in these patients.

Sonography in the diagnosis of cervical recurrence in patients with differentiated thyroid carcinoma.

OBJECTIVE: To determine the sensitivity of thyroglobulin (Tg), iodine scanning, and sonography in the diagnosis of cervical recurrence of thyroid cancer. METHODS: This prospective study assessed 81 patients with cervical metastases or extrathyroid invasion at first appearance who underwent clinical examination, scanning, measurement of Tg after thyroxine withdrawal, and sonography about 8 months after thyroidectomy followed by radioiodine treatment. Only patients without distant metastases and without anti-Tg antibodies were included. RESULTS: Fifty patients showed persistence of the disease in the cervical region, with only 16% of them having had a suspicion on clinical examination, 33 with Tg levels of 2 ng/mL or greater (66% sensitivity), and 29 with positive scan findings (58% sensitivity). A combination of the 2 methods detected disease in 40 (80%) of 50 patients but failed to show 20% of cases that were identified by sonography and confirmed by fine-needle aspiration. Sonography had sensitivity of 96%. Specificity values for Tg, iodine scanning, and sonography were 80.6%, 90.3%, and 87%, respectively. CONCLUSIONS: Classic follow-up methods may not detect cervical disease in some patients with differentiated thyroid carcinoma, and sonography is necessary even in patients apparently free of the disease.