CLINICAL-EVALUATION OF UPPER MEDIASTINAL DISSECTION FOR DIFFERENTIATED THYROID-CARCINOMA

Background. An extensive upper mediastinal dissection in advanced diff erentiated thyroid carcinoma is occasionally required. This investigat ion was undertaken to clarify the indications for mediastinal lymph no de dissection and the route of upper mediastinal metastases. Methods. Twenty-one patients with differentiated thyroid cancer, who underwent their first radical operations with mediastinal dissection through a p artial midline sternotomy, were enrolled in this study. Of 21 patients , 10 (48%) were found to have mediastinal lymph node metastases. Resul ts. The tumor size in the group with metastatic disease was much bigge r than that in the group without metastatic disease. Histologic type a nd age were similar between the two groups. The extent of cervical lym ph node metastases was more significant in the group with metastatic d isease; in particular, all 10 patients showed more than two metastatic nodes along the internal jugular vein of the tumor-free side. Conclus ions. This study indicates that metastases to the internal jugular cha in on the side contralateral to the primary tumor would be an extremel y important factor for indication of extensive upper mediastinal lymph node dissection after median partial sternotomy in patients with diff erentiated thyroid carcinoma.