Randomized trial of prophylactic ipsilateral central lymph node dissection in patients with clinically node negative papillary thyroid microcarcinoma.

Abstract

This study aimed to evaluate the role of prophylactic ipsilateral central neck dissection (pCND) in patients with clinically node-negative (cN0) papillary thyroid microcarcinoma (PTMC). In this randomized control trial, a total of 164 consecutive patients were enrolled. By double-blinded randomization protocol, patients were allocated into hemithyroidectomy with pCND (n = 82) or without pCND (n = 82). With intention-to-treat analysis, post-surgical pathological and clinical course, surgery-related complications, causes and clinical course of protocol-violated cases and 5-year recurrence-free survival were compared. Operation time, hospital stay, and post-surgical complication were not significantly different between the two groups. In the pCND (+) group, occult lymph node metastasis rate was 50.0%, and lymph node ratio (metastatic/harvested lymph nodes) was 45.2%. Ten patients in the pCND (+) group had converted to undergo onsite or staged completion total thyroidectomy due to the presence of metastatic central lymph nodes and/or positive resection margin. Until last follow-up (mean 73.4 months), one regional recurrence developed in the pCND (-) group, and three regional recurrences occurred in the pCND (+) group. Five-year recurrence-free survival was similar between the two groups. Although ipsilateral pCND could clear occult lymph node metastasis in the central compartment, it failed to provide any oncological benefit for cN0 PTMC patients.