Correlation between Surgical Extent and Prognosis in Node-Negative, Early-Stage Papillary Thyroid Carcinoma Originating in the Isthmus

Background: The association between surgical extent and prognosis in papillary thyroid carcinoma originating in the isthmus is unclear. Methods: We included 233 patients with early-stage, node-negative papillary thyroid cancer originating in the isthmus; 126 were treated by lobectomy plus isthmusectomy with ipsilateral central neck dissection and 97 were treated by total thyroidectomy with bilateral central neck dissection. Subgroup analysis was performed according to tumor size (≤1 vs. >1 cm) to evaluate whether tumor size had a significant impact on determining the optimal extent of surgery in our cohort. Results: Total thyroidectomy patients had longer recurrence-free survival (RFS) than those treated by lobectomy plus isthmusectomy. Subgroup analysis showed that this was true only for tumors >1 cm. In multivariate analysis, total thyroidectomy was an independent risk factor for RFS only for tumors >1 cm. Conclusions: Lobectomy plus isthmusectomy may be optimal for early-stage, node-negative papillary thyroid carcinoma originating in the isthmus for tumors ≤1 cm; total thyroidectomy might be better for tumors >1 cm.