Correspondence (reply): In Reply

Dralle (1) developed the technique of compartment-oriented microdissection of the central and lateral compartments in patients with thyroid carcinoma in the early 1990s; this technique then became a consensus-backed part of the guidelines (2). While today prophylactic compartment resection has generally been abandoned in patients with intrathyroid papillary and follicular cN0 carcinoma in whom preoperatively or intraoperatively no lymph-node metastasis is suspected, there is a consensus that compartment-oriented lymph-node dissection should be performed where therapeutically indicated. With regard to the extent of lateral compartment resection, the specialist societies (1, 2) draw particular attention to the risk of morbidity associated with the nerves and the thoracic duct located in the lateral compartment and recommend that the extent of the resection should depend on tumor involvement (Table 2, in [3]). Thus, in patients with no signs of lymph-node metastasis, it is acceptable to not perform lymph-node dissection to minimize the risk of intraoperative injury to the marginal mandibular branch of the facial nerve or to the accessory nerve to prevent associated functional impairments (2).

For papillary carcinoma, it has long been proven that the extent of lymph-node involvement is a prognostic risk factor, especially for the risk of distant metastasis (4). The strategy of compartment resection is based on this. Whether lymph-node micrometastasis as opposed to lymph-node macrometastasis has a significant impact on survival beyond its role as a risk indicator remains unclear. Based on the current consensus of the specialist societies, the individualized risk/benefit assessment with regard to the extent of compartment resection favors a tumor involvement-oriented resection strategy, taking into account local macroscopic and, in case of distant metastasis, also distant tumor involvement.