Incidence of malignancy in thyroid nodules determined to be follicular lesions of undetermined significance on fine-needle aspiration.

BACKGROUND: Fine-needle aspiration (FNA) for thyroid nodules is the most important method for determining a diagnosis. The system for reporting results is based on a cytopathologic classification that stratifies the risk of malignancy. METHODS: We retrospectively studied 197 patients who underwent FNA for diagnostic evaluation of a thyroid nodule and had their results reported as a follicular lesion of undetermined significance (FLUS) using the Bethesda classification system. The objective of the study was to analyze the incidence and histopathologic types of malignancy in these cases. RESULTS: The final histopathologic breakdown is as follows: 65 cases (32.9%) of follicular adenoma, 81 cases (41.1%) of microfollicular adenomatoid nodule, 19 cases (9.6%) of microfollicular adenomatoid nodule on the background of thyroiditis, 17 cases (8.6%) of follicular carcinoma, 9 cases (4.6%) of follicular variant papillary carcinoma, and 6 cases (3.1%) of classic papillary carcinoma, for a 16.2% incidence of malignancy. Beyond these diagnoses in the FNA-biopsied nodules, we observed 29 cases (14.7%) of incidental ipsilateral papillary thyroid microcarcinoma (PTM) and 13 cases (6.6%) of incidental contralateral thyroid lobe PTM. CONCLUSIONS: This study observed a 16.2% incidence of thyroid cancer in the nodule designated FLUS compared to the 5 to 15% rate reported by the Bethesda FNA classification. The overall incidence of incidental PTM in the thyroid gland was 21.3%. These data support considering surgical intervention for at least diagnostic purposes in a patient with the FNAB diagnosis of FLUS.

The incidence of central neck micrometastatic disease in patients with papillary thyroid cancer staged preoperatively and intraoperatively as N0.

BACKGROUND: In papillary thyroid cancer, the incidence of regional lymph node metastasis in the central compartment has been reported to be between 21% and 60%. This study sought to establish the rate of micrometastatic disease in the central neck in patients staged as N0 by preoperative and intraoperative assessment. METHODS: We studied 72 consecutive patients with diagnoses of papillary thyroid cancer without preoperative or intraoperative evidence of central neck metastases. They underwent total thyroidectomies and were given elective central compartment neck dissection (CCND) ispsilateral to the lobe harboring the tumor or bilaterally in cases of primary tumor located in the isthmus. RESULTS: Of the patients, 30 underwent right CCND, 30 underwent left CCND, and in 12 cases the dissection was bilateral. The incidence of lymph node micrometastasis was 25%. Male gender and histologic type showed association with lymph node micrometasis. Among these cases, 7% had temporary vocal cord palsy, and 8% had temporary hypoparathyroidism. No cases of definitive vocal cord palsy or definitive hypocalcemia were observed. After the procedure 8 patients were up-staged according to the American Joint Committee on Cancer staging system. CONCLUSION: Despite being a safe procedure, this relatively low rate of micrometastatic disease emphasizes the need for a careful weighing of the risks and benefits of elective CCND.

Avaliação ultrassonográfica das metástases linfonodais para nível VI em pacientes com carcinoma bem diferenciado da tireoide / Ultrasonographic evaluation of the lymph node metastasis to level VI in patients with well differentiated thyroid carcinoma

Introdução: No Carcinoma Bem Diferenciado da Tireoide (CBDT),a metástase linfonodal para o Nível VI parece não somente serum fator prognóstico para a recorrência da doença, mas tambémpara a sobrevida dos pacientes. No entanto, há poucos estudosque avaliaram o desempenho da ultrassonografia em detectarmetástases linfonodais para essa região. Objetivo: Avaliar odesempenho da ultrassonografia na detecção de metástasespara Nível VI além de relacioná-las com as característicasclínico-patológicas da amostra em estudo. Método: Estudotransversal com análise retrospectiva dos laudos histopatológicose de ultrassonografia pré-operatória de pacientes com CBDTsubmetidos a tireoidectomia total e dissecção linfonodal deNível VI no período de março de 2006 até fevereiro de 2008.Resultados: Amostra final de 37 pacientes em que foramobservados predomínio do sexo feminino (83,78%), média deidade de 49,54 anos e maioria com carcinoma papilífero (91,89%).Oito pacientes (21,62%) apresentaram metástase para Nível VI.O número de linfonodos dissecados se correlacionou de maneiraestatisticamente significante com a presença dessas metástases(p=0,026), o que não se observou quanto ao do sexo, faixaetária e subtipo histológico desses pacientes. A ultrassonografiaapresentou 62,50% de sensibilidade, 51,72% de especificidade,valor preditivo positivo de 26,31%, valor preditivo negativo de83,33% e acurácia de 54,05%. Conclusão: A ultrassonografiaé um exame confiável nesse contexto principalmente quandodiante de um resultado negativo, devido ao alto valor preditivonegativo encontrado. A única característica clínico-patológica daamostra correlacionada de maneira estatisticamente significantecom a presença de metástases naquela região foi o número delinfonodos dissecados por paciente.

Background: In the Well Differentiated Thyroid Carcinoma(WDTC), the lymph node metastasis to level VI does not seem tobe only a prognostic factor of recurrence, but also of the patients?survival. However, there are only a few studies that evaluated theultrasonography?s performance to detect lymph node metastasisin that location. Objective: To assess the ultrasonography?sperformance to detect lymph node metastasis in level VI and totry to find a correlation between the patients? clinicopathologicfeatures and that metastasis. Method: A transversal study withthe retrospective analysis of the histophatologic and preoperativeultrasonography reports of patients with WDTC who underwent atotal thyreoidectomy and level VI dissection in the period betweenMarch 2006 and February 2008. Results: Final sample of 37patients in which were observed a predominance of female sex(83,78%), with median age of 49,54 years and most of themwith papillary carcinoma (91,89%). Eight patients (21,62%) hadmetastasis in level VI. The number of dissected lymph nodes hada statistically significant correlation with metastasis (p=0,026),what was not observed with the sex, age group and histologicsubtype. The ultrasonography showed 62,50% of sensibility,51,72% of specificity, positive predictive value of 26,31%, negativepredictive value of 83,33% and 54,05% of accuracy. Conclusion:The ultrasonography showed confiability in this context mainlywhen facing a negative result due the high negative predictivevalue found. The only patients? clinicopathologic feature with astatistically significant correlation with the level VI metastasis wasthe number of dissected lymph nodes.

Cytological criteria to predict basal phenotype of breast carcinomas.

Breast carcinoma is a heterogeneous disease. It can be classified into phenotypes based on the expression of certain proteins, with distinct differences in prognosis. The basal phenotype is associated with worse prognosis and it still remains without specific treatment. However, there is currently no international consensus on the cytological criteria that could predict this phenotype. The purpose of the study was to evaluate the cytological criteria in fine-needle aspiration biopsy and to identify their association with the basal phenotype of breast carcinoma. Fine-needle aspiration biopsy specimens and tissue sections (mastectomy specimen) from 74 cases of high-grade invasive ductal breast carcinomas were consecutively retrieved from the files of three institutions. Breast carcinomas were studied using the tissue microarray technique, being classified into phenotypes: luminal A, luminal B, HER2 overexpression, and basal. The cytological criteria for all cases were reviewed blindly by two pathologists according to five cytological criteria: cellularity, cell pattern, presence of necrosis, nucleoli, and nuclear atypia. Exact Fisher test was used to test the association between cytological criteria and the phenotypes of breast carcinoma. Necrosis was present in 64.7% of basal breast carcinomas, and 31.1% of nonbasal breast carcinomas, and that result was statistically significant, showing an odds ratio (OR) of 3.80. The basal phenotype, compared with the luminal A, showed more necrosis (OR = 6.97), present/prominent nucleoli (OR = 8.18), and cellularity more frequently (OR = 18.03). Necrosis, as well as present/prominent nucleoli and abundant cellularity are criteria more frequently associated to the basal phenotype of breast carcinoma.

Rhabdomyomatous carcinoma of the thymus.

Myoid cells have been described in the thymus in association with a variety of benign and malignant conditions. The presence of a benign rhabdomyomatous component in a malignant primary thymic epithelial neoplasm, however, is extremely rare. A case of poorly differentiated carcinoma of the thymus arising in the posterior mediastinum containing a prominent rhabdomyomatous component is described. The patient, a 70-year-old woman, was seen for a large posterior mediastinal mass. An open chest biopsy revealed an extensively necrotic tumor composed of islands of atypical cells with vesicular nuclei and prominent nucleoli with numerous mitotic figures admixed with abortive glandular structures. Interspersed with the malignant epithelial components were islands of large cells containing brightly eosinophilic cytoplasm and small, round, excentrically placed nuclei. Immunohistochemical studies showed strong positivity of the epithelial cells for cytokeratin and strong positivity of the myoid cells for pan-actin, desmin, and myogenin. The possible relationship of the rhabdomyomatous component of this tumor with the myoid cells of the thymus is discussed.

Incidentalomas de tiróide: comparaçäo dos achados ultra-sonográficos com o diagnóstico citopatológico / Thyroid incidentalomas: comparison between the ultrasonography finding and the cythopatologic diagnosis

Nódulos tireoideanos impalpáveis, descobertos principalmente por ultrasonografia (USG), São denominados "incidentalomas". Sua importância, além da alta prevalência, está na possibilidade da detecão de "carcinoma oculto". Este trabalho objetiva estudar características ultrasonográficas dos incidentalomas de tiróide confrontadas com diagnóstico citopatológico obtido pela punção-biósia aspirativa por agulha fina (PBAAF) guiada por USG. Realizou-se um estudo transversal descritivo dos nódulos tireoideanos classificados como "incidentalomas", cujos pacientes, sabidamente portadores dos mesmos por exames prévios, foram submetidos à PBAAF-USG, de janeiro/1996 a maio/1998, em clínica radiológica. Os estudos ultra-sonográfico e citopatologico foram realizados pela mesma equipe médica, considerando-se a citopatologia como padrão-ouro. Nódulos > 1,5cm foram excluídos. No período de estudo, 110 nódulos foram examinados (95 pacientes, alguns portadores de nódulos múltiplos). À citopatologia, 74 por cento dos nódulos eram benignos, 10 por cento malignos e 16 por cento com citodiagnóstico de lesão indeterminada (desconsiderados da análise estatística). Os nódulos malignos apresentaram predomínio das seguintes características à USG: conteúdo sólido (1000 por cento), margens irregulares (54 por cento) e microcalcificações (54 por cento), com diferenças estatisticamente significantes dos benignos. Em 72 por cento dos nódulos malignos, havia pelo menos 3 das 5 características indicativas de malignidade: hipoecogenicidade, conteúdo sólido, halo ausente, margem irregular e microcalcificações. A maioria dos incidentalomas estudados foi benigna. As características ultra-sonográficas-conteúdo sólido, margens irregulares e microcalcificações, principalmente quando associadas, devem ser valorizadas ao se investigar malignidade.

Análise da acurácia da punção aspirativa por agulha fina de nódulo de tireóide / Analysis of the accuracy of Fine Needle Aspiration biopsy of Thyroid nodule

Estudos sugerem que o uso rotineiro da PAAF de tireóide modificou a abordagem das doenças da tireóide. Porém, é necessário conhecer o valor da PAAF como meio diagnóstico destas lesões. O objetivo deste estudo foi avaliar a acurácia da PAAF em doenças nodulares da tireóide em nosso meio. Método: foram estudados os resultados do exame citopatológico e histopatológico de 72 pacientes que realizaram a PAAF e posteriormente o tratamento cirúrgico do nódulo tireoídeo, entre julho/1996 e outubro/2000. A histopatologia foi considerada padrão-ouro nesta análise e os nódulos foram classificados em benignos ou malignos. Na citopatologia, os laudos foram agrupados em: benignos, malignos e indeterminados. As amostras insatisfatórias foram excluídas do estudo. Resultados: dos 72 casos operados, 45,8% eram neoplasias malignas, sendo o carcinoma papilar o mais freqüente (79,2%). Das lesões com laudo citopatológico indeterminado, 17 (70,8%) eram benignas e 7 (29,2 %) eram malignas. Os valores obtidos foram: sensibilidade de 93,9%, especificidade de 56,4%, valor preditivo negativo de 91,7%, valor preditivo positivo de 64,6%, índice de falso-positivo de 43,6%, índice de falso-negativo de 6,1 % e acurácia de 73,6%. Quanto ao carcinoma papilar, 28 dos 30 casos (93,3%) foram diagnosticados pela PAAF. Discussão: a PAAF representa um excelente teste no screening das doenças da tireóide, pela alta sensibilidade. Sua maior limitação neste estudo foi o grande número de laudos citopatológicos indeterminados, levando a um aumento do índice de falsos-positivos e reduzindo sua especificidade. A PAAF demonstrou ainda possuir alta sensibilidade e especificidade para o carcinoma papilar...