Extent of thyroid surgery for clinically node-negative papillary thyroid carcinoma with confirmed nodal metastases after prophylactic central neck dissection: a 15-year experience in a single center

PURPOSE: The use of prophylactic central neck dissection (PCND) and the extent of thyroid surgery in clinically node-negative (cN0) papillary thyroid carcinoma (PTC) are controversial. This study aimed to investigate whether the extent of thyroid surgery influences the prognosis of patients with PTC with central lymph node metastasis (N1a), which was cN0 but pathologically confirmed after PCND. METHODS: This was a single-center retrospective study using medical records. Patients who underwent thyroid surgery with PCND for the treatment of PTC between 2004 and 2019 were included. Predictive factors and local recurrence rates were analyzed. RESULTS: Of 2,274 patients with cN0 PTC, 436 were confirmed to have pathologic N1a disease after PCND. Among them, 340 patients (78.0%) underwent total thyroidectomy (TT) and 96 patients (22.0%) underwent less than TT. Of the 374 patients who were followed up for >6 months, 5 (1.3%) experienced recurrence. The 15-year recurrence-free survival (RFS) rate was 98.2%. No clinicopathologic factor was predictive of tumor recurrence. RFS tended to be lower in patients who underwent less than TT than in those who underwent TT; however, the difference was not statistically significant. CONCLUSION: Our study showed low recurrence rates in patients with cN0 PTC pathologically confirmed as N1a after PCND. The RFS did not differ according to the extent of thyroid surgery. Considering the low recurrence rate and the surgical morbidity associated with thyroid surgery, less than TT with PCND may be considered for patients with cN0 unilateral PTC even with a pathologic staging of N1a after PCND.