Lateral and mediastinal lymph node dissection in differentiated thyroid carcinoma: Indications, benefits, and risks

Background: There are 3 compartments of regional lymph nodes to which thyroid carcinoma metastasizes: central, lateral, and mediastinal compartments. The central compartment is the nearest to the thyroid and usually dissected routinely. However, the indication for dissection of the lateral and mediastinal compartments for differentiated thyroid carcinoma remains an open question. Methods: The indication for dissection of lateral and mediastinal compartments is evaluated based on previous reports, including those from our department. Results: There is nothing controversial about the indication for therapeutic lateral node dissection for tumors with clinically apparent lateral node metastasis. Such cases are more likely to show recurrence, especially in previously dissected compartments, and surgeons must perform dissection carefully. Although there are no randomized studies on the indication for prophylactic lateral node dissection, it is recommended for papillary carcinoma with aggressive characteristics such as large size and massive extrathyroid extension. Prophylactic mediastinal dissection via median sternotomy is not recommended. Conclusions: Node dissection of the lateral and mediastinal compartments must be performed aggressively and radically to prevent recurrence in previously dissected regions.