8-A837A-2017-Books-00129-029-060_Katz_Sec1_Ch02-ROUND-1

S E C T I O N I | T H Y R O I D

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Cricoid cartilage

Superior parathyroid gland Common carotid artery

RLN Inferior parathyroid gland Esophagus Metastatic lymph nodes

FIGURE 2-5  Metastatic lymph nodes posterior to recurrent laryngeal nerve (RLN).

the right side (Fig. 2-5). Central compartment nodal metastasis can also be situated posterior to the common carotid arteries and posterior to the innominate artery on the right, and care should be taken to include these lymph nodes during CCND. The retropharyngeal lymph nodes are rarely involved in PTC; however, primary tumors in the superior pole can metastasize to this location. 92,93 Cervical ultrasonography will not visualize the retropharyngeal space, and contrast-enhanced cross-sectional imag- ing (typically CT) can be useful in evaluation if retropharyngeal and retroesophageal space involvement is suspected (Fig. 2-6). A CCND can be executed either by en bloc resection of the lymph nodes with the thyroid specimen or by separate resection. Removal of the thyroid initially may allow for easier visualization of the lymph nodes posterior to the thyroid and along the course of the RLN. Removal of the entire lymph node basin is recommended in patients with clinical involvement, and “berry picking” or “plucking” of individually involved nodes is not recommended and is associated with higher rates of persistent disease. 42,94,95 Typical nodal yield from a bilateral level VI lymph node dissection can vary greatly; however, a recent study noted that patients with recurrent papillary thy- roid cancer (PTC) had a lower mean nodal yield than those without recurrence, thus suggesting the importance of a complete CCND in the presence of nodal metastasis. 96 Exposure of the entire anterior surface of the RLN is recommended, from its insertion point at the cricothyroid muscle to its proximal extent as it emanates from the medi- astinum. This allows for removal of the lymph nodes anterior to the RLN with direct