Comparison of safety and efficacy between total endoscopic resection and conventional open surgery for malignant thyroid tumors: a meta-analysis

Background: Endoscopic thyroidectomy (ET) has been widely accepted as a surgical option for benign thyroid lesions, yet remains controversial in the treatment of malignant thyroid because of concerns with the safety and efficacies. This paper aims at systematically evaluating the advantages and disadvantages of ET in malignant thyroid tumors through meta-analyses. Methods: Meta-analysis was conducted by retrieving all studies on the treatment of malignant thyroid carcinomas released in database, including PubMed, Web of Science, Cochrane and Google scholar, from January 2005 to January 2019. Then the safety and efficacies were compared between the two surgical modalities based on current reports. Results: Totally, 3,482 cases were included in 11 related studies. Most adverse outcomes by ET were involved in transient or permanent recurrent laryngeal nerve paralysis (RLN) and hypocalcemia, postoperative total complications, hemorrhage, hematoma at the incision, and total relapse rate following surgery. Besides, ET led to higher incidence of transient RLN palsy, yet significantly lower transient hypocalcemia than conventional open thyroidectomy (COT). The difference was insignificant regarding transient or permanent RLN and hypocalcemia, total postoperative complications, postoperative hemorrhage, incisional hematoma and total recurrent rate between the two procedures. Secondary outcomes consisted of operative time, hospital stay and cosmetic results, by which COT was superior to ET, yet cosmetic incision was better by ET than by COT. There was no significant difference in hospital stay. Conclusions: ET can be feasible and safe surgical option for malignant thyroid lesions, with better cosmetic effect.