Prophylactic central neck dissection has no advantage in patients with metastatic papillary thyroid cancer to the lateral neck

Background: Papillary thyroid cancer (PTC) usually metastasizes via lymphatic channels in a sequential fashion, first to the central compartment, followed by the lateral neck. PTC patients diagnosed with lateral neck disease (N1b) without proof for central involvement traditionally undergo prophylactic central neck dissection (pCND). However, substantial evidence on outcomes to support this approach is lacking. Materials and Methods: We conducted a dual center retrospective study to compare the rate of central neck recurrence between N1b PTC patients undergoing pCND and those spared pCND. All patients diagnosed with N1b PTC who underwent total thyroidectomy and lateral neck dissections with or without pCND between January 1998 and December 2015 were included in this study. The rates of central neck recurrences were compared between the groups. Results: The 111 patients who met the inclusion criteria were 44 females (39.6%) and 67 males (60.4%), with a mean age of 50.2 ± 17.7 years, and a mean follow-up of 10.2 ± 5.3 years. Sixty patients (54.1%) underwent a pCND and 51 patients (45.9%) did not (non-pCND). During follow-up, 18 patients (16.2%) had level VI recurrences, 13 in the pCND group and 5 in the non-pCND group. Cox-regression models with propensity scoring did not reveal any inclination or an advantage for performing pCND. Conclusion: The present study demonstrated no advantage in performing pCND to prevent central neck recurrence among PTC patients with lateral neck involvement only. These findings question the need for pCND in patients without clinical evidence of central neck disease.