Disease-free survival is the main outcome of interest considered when assessing the effectiveness of surgical management of papillary thyroid carcinoma (PTC). Specific characteristics of nodal metastases have been demonstrated to impact the risk of recurrence. We sought to verify the oncologic rationale of prophylactic central compartment neck dissection (pCCND) in the management of PTC by comparing the pathologic spectrum of lymph nodes in patient's undergoing pCCND vs. therapeutic CCND (tCCND).

Between May 2017 and October 2018, 257 patients underwent total thyroidectomy for PTC. pCCND was performed for clinically uninvolved nodes, and tCCND for clinically apparent nodal disease. Harvested metastatic nodes from each group were compared in terms of number, size, and the presence of extranodal extension. Cut-off values for the size and number were 2 mm and 5, respectively. Patients were followed until October 2023.

78 patients underwent tCCND. Whereas pCCND was performed in 179 patients. The mean number of nodes harvested from tCCND was 14 (9-31), and 9 (5-24) from pCCND (p<0.0001). Node positivity was 84.6%, and 37.4%, respectively (p<0.0001). ≥ 5 metastatic nodes were seen in 66.6% of tCCND vs. 7.5% of pCCND (p<0.0001). 73% of tCCND had a metastatic node ≥ 2mm in size vs. 2.5% of pCCND (p<0.0001). extranodal extension occurred in 25% of tCCND vs. 2.5% of pCCND (p=0.01). The recurrence rate was 2.8% for tCCND vs. 0% for pCCND. The recurrence rate was 2.8% for tCCND vs. 0% for pCCND (p<0.0001).

Clinically inapparent nodal disease has a pathologic spectrum with insignificant impact on disease recurrence. Therefore, pCCND does not seem to be oncologically meaningful.