Treatment of Mediastinal Lymph Node Metastases in Differentiated Thyroid Carcinoma

ABSTRACT

PURPOSE: In case of well-differentiated thyroid carcinoma, a mediastinal lymph node metastasis is extremely rare, but can be life threatening due to its proximity to the vital organs. The consequence of radical extirpation must be balanced against the issues of tumor control, survival outcomes, functional morbidity, and the sequelae of an excessive surgical resection. The aim of this study was to clarify the clinicopathological characteristics, treatment and outcomes of patients with mediastinal lymph node metastasis in differentiated thyroid carcinoma. METHODS: Nineteen consecutive differentiated thyroid carcinoma patients with a mediastinal lymph node metastasis between June 1998 and Feb. 2004 were included in this study. All the patients underwent a trans-sternal mediastinal lymph node dissection in addition to thyroid cancer surgery. The median follow-up was 40.7 months (range, 18~97). RESULTS: The mean age was 49 years (range 31~72 years) with a male-to-female ratio of 8 11. The surgical treatment included 11 cases of an upper mediastinal lymph nodes dissection via a partial sternotomy and 7 cases of a whole mediastinal lymph nodes dissection via a total longitudinal sternotomy. In 6 cases, the combined resection of the involved organ was added. Major postoperative complications occurred in two patients, one with leakage from a tracheoesophageal fistula and the other with a pulmonary embolism. During the follow-up period, local recurrences in the lateral cervical nodes were observed in 5 cases. The 5 year overall survival and 5 year disease-free survival were 90.5% and 63.6%, respectively. There was only one surgical mortality. CONCLUSION: These results suggest that the prognosis for mediastinal lymph node metastasis in differentiated thyroid carcinoma can be improved by an aggressive mediastinal node dissection and the appropriate thyroid cancer surgery.