Prophylactic central neck dissection and local recurrence in papillary thyroid microcarcinoma: a meta-analysis / Esvaziamento cervical central profilático e recidiva local de microcarcinoma papilífero de tireoide: uma metanálise

Abstract Introduction: For papillary thyroid microcarcinoma patients, the reported incidence of lymph node metastasis is as high as 40%, and these occur mainly in the central compartment of the neck. Because these metastases are difficult to detect using ultrasonography preoperatively, some authors advocate routine central neck dissection in papillary thyroid microcarcinoma patients at the time of initial thyroidectomy. Objective: To evaluate whether prophylactic central neck dissection can decrease the local recurrence rate of papillary thyroid microcarcinoma after thyroidectomy. Methods: The publicly available literature published from January 1990 to December 2017 concerning thyroidectomy plus prophylactic central neck dissection versus thyroidectomy for papillary thyroid microcarcinoma was retrieved by searching the national and international online databases. A meta-analysis was performed after the data extraction process. Results: Four studies were finally included with a total of 727 patients, of whom, 366 cases underwent thyroidectomy plus prophylactic central neck dissection and 361 cases received thyroidectomy only. As shown by the meta-analysis results, the recurrence rates in cases of thyroidectomy plus prophylactic central neck dissection were approximately 1.91% and were significantly lower than those with thyroidectomy only (OR = 0.24, 95% CI [0.10, 0.56], p = 0.0009). Conclusion: For patients with papillary thyroid microcarcinoma, thyroidectomy plus prophylactic central neck dissection is a safe and efficient procedure and it results in lower recurrence rate. Since the evidences are of low quality (non-randomized studies), further randomized trials are needed.

Resumo Introdução: A incidência relatada de metástases linfonodais chega a 40% em pacientes com microcarcinoma papilífero de tireoide e essas ocorrem principalmente no compartimento cervical central. Como essas metástases são difíceis de ser detectadas com o uso de ultrassonografia no pré-operatório, alguns autores defendem o esvaziamento cervical central de rotina em pacientes portadores de microcarcinoma papilífero de tireoide no momento da tireoidectomia inicial. Objetivo: Avaliar se o esvaziamento cervical central profilático pode diminuir a taxa de recorrência local de microcarcinoma papilífero de tireoide após a tireoidectomia. Método: A literatura disponível, publicada de janeiro de 1990 a dezembro de 2017, sobre tireoidectomia com esvaziamento cervical central profilático versus tireoidectomia somente para microcarcinoma papilífero de tireoide foi obtida através de busca nas bases de dados online nacionais e internacionais. A metanálise foi feita após o processo de extração de dados. Resultados: Quatro estudos foram finalmente incluídos na metanálise, com 727 pacientes, dos quais 366 foram submetidos à tireoidectomia com esvaziamento cervical central profilático e 361 só receberam tireoidectomia. Como mostrado pelos resultados da metanálise, as taxas de recorrência com tireoidectomia com esvaziamento cervical central profilático foram de 1,91% e foram significantemente menores do que aquelas em pacientes submetidos somente à tiroidectomia (OR = 0,24, IC95% [0,10-0,56], p = 0,0009). Conclusão: Para pacientes com microcarcinoma papilífero de tireoide, o esvaziamento cervical central profilático é um procedimento seguro e eficiente e resulta em menor taxa de recorrência. Como as evidências são de baixa qualidade (estudos não randomizados), mais estudos randomizados são necessários.

Prophylactic central neck dissection and local recurrence in papillary thyroid microcarcinoma: a meta-analysis.

INTRODUCTION: For papillary thyroid microcarcinoma patients, the reported incidence of lymph node metastasis is as high as 40%, and these occur mainly in the central compartment of the neck. Because these metastases are difficult to detect using ultrasonography preoperatively, some authors advocate routine central neck dissection in papillary thyroid microcarcinoma patients at the time of initial thyroidectomy. OBJECTIVE: To evaluate whether prophylactic central neck dissection can decrease the local recurrence rate of papillary thyroid microcarcinoma after thyroidectomy. METHODS: The publicly available literature published from January 1990 to December 2017 concerning thyroidectomy plus prophylactic central neck dissection versus thyroidectomy for papillary thyroid microcarcinoma was retrieved by searching the national and international online databases. A meta-analysis was performed after the data extraction process. RESULTS: Four studies were finally included with a total of 727 patients, of whom, 366 cases underwent thyroidectomy plus prophylactic central neck dissection and 361 cases received thyroidectomy only. As shown by the meta-analysis results, the recurrence rates in cases of thyroidectomy plus prophylactic central neck dissection were approximately 1.91% and were significantly lower than those with thyroidectomy only (OR=0.24, 95% CI [0.10, 0.56], p=0.0009). CONCLUSION: For patients with papillary thyroid microcarcinoma, thyroidectomy plus prophylactic central neck dissection is a safe and efficient procedure and it results in lower recurrence rate. Since the evidences are of low quality (non-randomized studies), further randomized trials are needed.

Relato de caso: Microcarcinoma papilífero de tireoide com metástase para calota craniana / Case Report: Papillary thyroid microcarcinoma with metastasis to skull cap

Introdução: O câncer de tireoide é considerado a quarta neoplasia maligna mais frequente nas mulheres brasileiras. Sua incidência vem aumentando, principalmente pelo aumento dos diagnósticos de carcinomas papilíferos, que apresentam baixo índice de, porém podem ocasionar metástases linfonodal, pulmonar e óssea. Relato de caso: O caso relatado é de um paciente do sexo masculino, de 62 anos, que procurou o serviço devido a abaulamento em região parietal direita há cinco meses; com evidência de volumosa lesão expansiva heterogênea em calota craniana, exercendo efeito compressivo sobre o parênquima à Tomografia Computadorizada de Crânio. Após exérese, anatomopatológico mostrou neoplasia papiliforme com invasão óssea, com imunohistoquímica indicando carcinoma metastático de tireoide com padrão morfológico de carcinoma papilífero. À ultrassonografia de tireoide: nódulo sólido (0,9 x 0,9 x 0,8 cm) em lobo direito, Classe V- ATA (alto grau de suspeita de malignidade pela ultrassonografia). Após tireoidectomia, anatomopatológico evidenciou carcinoma papilífero de tireoide, variante folicular. Conclusão: A importância do caso relatado reside na apresentação rara de microcarcinoma papilífero de tireoide, em paciente do sexo masculino de faixa etária acima do esperado, com metástase, por via hematogênica, à distância para a calota craniana sem metástase linfonodal.

Introduction: Thyroid cancer is considered the fourth most frequent malignant neoplasm in Brazilian women, and its incidence has been increased mainly by an increase in the diagnosis of papillary carcinomas, which present a low mortality rate, but sometimes may result in lymph node, lung and bone metastasis. Case report: The case reported is a 62-year-old male patient, who sought the service due to bulging in the right parietal region for 5 months; with evidence of a large heterogeneous expansive lesion in a skull cap exerting a compressive effect on the parenchyma on Cranial Computed Tomography. After excision, anatomopathological examination showed papilliform neoplasm with bone invasion, with immunohistochemistry indicating metastatic thyroid carcinoma with morphological pattern of papillary carcinoma. Thyroid ultrasonography: solid nodule (0.9 x 0.9 x 0.8 cm) in the right lobe, Class V-ATA (high degree of suspicion of malignancy by ultrasonography). After thyroidectomy, anatomopathological evidence showed papillary thyroid carcinoma, variant follicular. Conclusion: The importance of the reported case lies in the rare presentation of papillary microcarcinoma of the thyroid, in a male patient older than expected, with hematogenous metastasis distal to the skull cap without lymph node metastasis.