PTH and differentiated thyroid carcinoma: Abbreviations: ETSA, endoscopic thyroidectomy via the submental approach; COT, conventional open thyroidectomy; TOETVA, transoral endoscopic thyroidectomy vestibular approach; iPTH, intact parathyroid hormone; DTC, differentiated thyroid carcinoma; ERAS, Enhanced Recovery After Surgery; QoL, quality of life; CND, central neck dissection; RLN, recurrent laryngeal nerve; VAS, visual analog scale; THYCA-QOL, Thyroid Cancer-specific Quality of Life.