All the patients underwent ultrasonographic, cytological, and biochemical follow-up for 60 months postoperatively. However, for all the consenting patients, the follow-up period was extended to 120 months postoperatively. All the patients were evaluated at 3, 6, 9, and 12 months postoperatively during the first year, and every 12 months for the following years. Biochemical evaluation consisted of determining serum TSH concentrations. Thyroid ultrasonography was performed by the same operator (MB) using the same equipment as in preoperative evaluation (Logiq 7; GE, Solingen, Germany). All the patients in this study, irrespectively of the individual group assignment, received postoperative levothyroxine treatment. The levothyroxine dose was adjusted to serum TSH concentrations to keep it within the lowest two-thirds of the reference range (0.3–2.5 mU/L). This therapeutic strategy was focused on avoiding the risk of mild thyrotoxicosis and limiting the excessive TSH stimulation of the thyroid remnants (in the DO and BST groups).