Comprehensive analysis of learning curve and surgical outcomes of endoscopic thyroidectomy for papillary thyroid carcinoma: a prospective study

Endoscopic thyroid cancer surgery has been widely carried out in the world, however, the learning curve of the technique is undetermined due to a lack of prospective and large sample-size studies. This study aims to prospectively evaluate the learning curve of endoscopic thyroidectomy in papillary carcinoma from multidimension and assess the outcomes. Data from 351 consecutive patients who underwent gasless transaxillary endoscopic thyroidectomy (GTET) were collected. Cumulative sum (CUSUM) analysis was applied to identify the learning curve of the operation time, number of retrieved lymph node(LN) and weight of dissection lymphatic tissue (WDLT). The differences in surgical outcome, surgical trauma, parathyroid gland(PG) function protection and quality of life (QOL) between learning phases were analyzed. Females predominated (86.7%) with a mean age of 34 years. Postoperative pathology in most cases was T1 (98.6%) and N0 (70.9%). The transition points of the operation time, space building time, thyroidectomy with central neck dissection time, and number of retrieved LN were 110, 133, 91 and 205 patients respectively. According to the CUSUM curves, there were 3 phases in the learning: phase 1 (patients 1-110), phase 2 (patients 111–205), and phase 3 (from patients 206). There were significant differences in operation time, blood loss, recovery, WDLT, PG function protection, surgical trauma and short-term QOL among the phases. The learning curve identified in our study was divided into 3 stages. We indicated that GTET is safe and feasible for indication-based selected patients.