갑상선암종의 후인두림프절 전이 = Retropharyngeal Lymph Node Metastasis from Thyroid Carcinoma

다국어 초록 (Multilingual Abstract)

Background and Objectives: Metastasis of the retropharyngeal lymph nodes (RPLNs) in thyroid cancer is rare. It is almost impossible to detect metastasis of the RPLNs by palpation or inspection. Images such as CT, MRI or PET/CT can be used for preoperative evaluation of RPLNs but the effectiveness of these radiologic diagnoses in detecting the PRLNs metastasis in thyroid cancer has not been reported. Our study goal is to identify the effectiveness of radiologic diagnosis by comparing preoperative radiologic findings with histopathologic results. We also tried to find clinical factors which are associated with RPLNs metastasis in thyroid cancer. Materials and Methods: We reviewed all patients who underwent resection of RPLN group because of thyroid cancer metastasis at our institution between 2003 and 2007. Total 6 patients were included in this study. All patients underwent retropharyngeal lymph node dissection and got histopathologic interpretation of the RPLNs. We compared the preoperative radiologic findings with postoperative histopathologic results. Results: Metastatic retropharyngeal nodes were successfully resected via transcervical approach in all patients. Metastasis to the RPLN group was confirmed hisotpathologically in all 6 patients (positive predictive value 100%). All 6 patients had multiple cervical lymph node metastases and among them, 5 patients had extrathyroid extension of primary tumor. Conclusion: Preoperative positive finding in radiologic studies such as CT, MRI and PET/CT perfectly predicted RPLN metastasis of thyroid cancer in this study. If patients with thyroid cancer have cervical lymph node metastasis, previous neck dissection history, or extrathyroidal extension, we have to keep the chance of RPLN metastasis in mind. Because of the high possibility of RPLN metastastis in cases of positive radiologic finding, we recommend the adding of RPLN dissection in these patients.