Long-Term Prognosis of Unilateral and Multifocal Papillary Thyroid Microcarcinoma After Unilateral Lobectomy Versus Total Thyroidectomy.

Abstract

Multifocal papillary thyroid microcarcinoma (PTMC) has been associated with poor outcomes; however, we often encounter pathologically confirmed unilateral multifocal PTMC after surgery. To date, no consensus on the proper surgical extent for patients with this form of PTMC has been reported. The aim of this study was to analyze the effect of the type of surgical treatment on disease recurrence in patients with unilateral multifocal PTMC. We retrospectively analyzed data from 255 patients with unilateral, multifocal, node-negative PTMC between March 1999 and December 2012. We evaluated two groups of patients: those who underwent unilateral lobectomy (Group I, n = 127) and those who underwent total thyroidectomy (Group II, n = 128). During the follow-up period, which lasted a median of 94.8 months, we assessed locoregional recurrence (LRR). There was no statistically significant difference between the two groups with regard to LRR at follow-up (3.15% for Group I vs. 0.78% for Group II; p = 0.244). The association between the type of surgical treatment and LRR remained nonsignificant after adjusting for potential confounders such as age, tumor size, microscopic extrathyroidal extension, and lymphovascular invasion (p = 0.115). During follow-up, the incidence of transient hypocalcemia (0% vs. 8.6%; p = 0.001) and vocal fold paralysis (1.6% vs. 9.4%; p = 0.011) was higher in Group II than in Group I. Even though randomized controlled trials are the only option to obtain a definitive answer to this question, unilateral lobectomy may be a safe operative option for selected patients with unilateral, multifocal, node-negative PTMC.