Thyroglossal duct cyst (TDC) is a cystic expansion of a remnant of the thyroglossal duct tract. Carcinomas in the TDC are extremely rare and are usually an incidental finding after the Sistrunk procedure. In this report, an unusual case of a 36-year-old woman with concurrent papillary thyroid carcinoma arising in the TDC and on the thyroid gland is presented, followed by a discussion of the controversies surrounding the possible origins of a papillary carcinoma in the TDC, as well as the current management options.

O objetivo do trabalho foi correlacionar as características ecográficas dos nódulos tireóideos aos achados citológicos, para determinar a importância da ultra-sonografia na doença nodular da tireóide. Foram realizadas punções aspirativas por agulha fina orientadas por ultra-som, após avaliação e classificação ecográfica de 436 nódulos. Obteve-se celularidade adequada para análise em 401 nódulos (92%), procedendo-se à correlação ecográfico/citológica. A classificação utilizada permitiu distribuir as características ecográficas de acordo com o risco de malignidade, identificando nódulos Grau III císticos com foco sólido (citologia positiva em 23,8%) e sólidos hipoecóicos (40%) como suspeitos e os Grau IV (95,2%) como altamente suspeitos. Os nódulos Grau II sólidos iso e hiperecóicos (5%) e mistos (1,9%), em acordo com a literatura, foram considerados provavelmente benignos. O ultra-som forneceu auxílio importante à avaliação clínica e determinação da conduta a ser tomada, devendo fazer parte dos protocolos para avaliação inicial e acompanhamento da doença nodular da tireóide.

<p class="abstract"><strong>Background:</strong> In patients with classic papillary thyroid carcinoma (PTC) and no clinical evidence of lymph node metastasis (cN0), elective central neck dissection remains controversial. This study evaluates whether elective ipsilateral central neck dissection (eICND) along with total thyroidectomy could modify the staging of these patients. Additionally, we aim to assess pN1 risk factors, the incidence of post-operative complications, and the correlation between pN1 and change in tumor classification according to the risk stratification score of the American thyroid association 2015 (ATA 2015-RSS) and the TNM Score.</p><p class="abstract"><strong>Methods:</strong> This is a prospective, observational study, involving 46 patients with cN0 PTC who underwent eICND along with total thyroidectomy. The number of metastatic lymph nodes, the largest lymph node metastasis, and the extra-nodal extension were assessed.  </p><p class="abstract"><strong>Results:</strong> 22 out of 46 patients (47.8%; CI 32.9–63.1) presented lymph node metastasis. Seventeen out of the 45 patients initially classified as low or intermediate ATA 2015-RSS upgraded their risk staging (37.8%; CI 23.8–53.5). Fourteen out of these reclassified patients had their initial ATA 2015-RSS changed due to lymph node metastasis larger than 2 mm (mostly between 3 mm and 4 mm). Ten out of 46 (21.7%; CI 10.49–36.4) patients had their TNM staging reviewed. General complication rate was 17.4% (8/46).</p><p class="abstract"><strong>Conclusions:</strong> Elective dissection of levels VI ipsilateral and VII showed the ability to upgrade the initial ATA 2015-RSS and TNM staging in patients with cN0 PTC. However, further studies are necessary to evaluate the clinical impact of lymph node micro-metastasis.</p>