TPO and multinodular goiter: HT, Hashimoto’s thyroiditis; DTC, differentiated thyroid cancer; RLN, recurrent laryngeal nerve; MNG, multinodular goiter; TT total thyroidectomy; GD, Graves’ disease; ATD, autoimmune thyroid disease; AST, acute suppurative thyroiditis; IJV, internal jugular vein; QoL, quality of life; anti-TPO-Ab, anti–thyroid peroxidase antibody; BG, benign goiter; NA, not available