Predictors of recurrence after total thyroidectomy plus neck dissection and radioactive iodine ablation for high-risk papillary thyroid carcinoma.

ABSTRACT

BACKGROUND: American Thyroid Association (ATA) proposed management guidelines for differentiated thyroid cancer, including a three-tiered risk stratification system for structural recurrence. This study aimed to compare the various 2015 ATA criteria for the strength of association with the recurrence of high-risk papillary thyroid carcinoma (PTC). STUDY DESIGN: This study included 545 consecutive patients who underwent total thyroidectomy plus neck dissection and radioactive iodine ablation (RAI) for previously untreated high-risk PTC. The association of recurrence-free survival (RFS) with clinicopathological factors was evaluated by univariate and multivariate Cox proportional hazard regression analyses. RESULTS: During a follow-up median period of 89 months, 90 (16.5%) patients had any-site recurrence. Of the high-risk factors, high stimulated thyroglobulin (sTg) level and >3-cm sized lymph nodes (LNs) were significantly associated with recurrence (all P < .005). Sex, tumor size, lymphovascular invasion, multifocality, number of positive LNs, extranodal extension, T and N classifications, and overall tumor-node-metastasis stage were also significantly associated with recurrence (all P < .05). In multivariate analyses, high sTg level [adjusted hazard ratio (HR) = 7.18] and N1b (adjusted HR = 3.27) were independent factors predictive of recurrence (all P ≤ .001). CONCLUSIONS: Postoperative high serum sTg level might be the most important predictor of PTC recurrence after total thyroidectomy plus neck dissection and RAI.