Assessing National Utilization Trends and Outcomes of Robotic and Endoscopic Thyroidectomy in the United States

Objective We aimed to evaluate trends and outcomes of surgical approaches to thyroid surgery. We hypothesized that there have been changes over time in the utilization of approaches to thyroidectomy, including endoscopic, robotic, and open approaches, and that patient outcomes may differ between open surgery and endoscopic or robotic approaches. Study Design Retrospective analysis. Setting The National Cancer Database (NCDB) was queried between 2010 and 2016. Subjects and Methods National cohort of patients. Descriptive statistics were performed using χ2 test, Mann-Whitney U test, t test and analysis of variance. To investigate complication rates, patient matching was performed with subsequent analysis using simple and multivariable logistic regressions. Results We identified 217,938 patients within the NCDB. While endoscopic thyroid surgery increased, relatively, in use over time (0.93% to 2.34% of cases in 2010 and 2016, respectively), robotic thyroid surgery started to decline relatively to other approaches from 2013 to 2016 (0.39% to 0.25% of cases, respectively). The endoscopic approach was performed more commonly than the robotic approach within individual facilities that have reported both procedures ( P = .025). Robotic thyroid surgery was associated with increased risk of positive margins ( P = .046), while endoscopic thyroid surgery was associated with a higher rate of unplanned hospital readmission (OR, 1.55; 95% CI, 1.09-2.22), longer inpatient stays (OR, 1.55; 95% CI, 1.19-2.02), and higher 90-day postoperative mortality (OR, 4.45; 95% CI, 1.58-12.6). Conclusion Endoscopic thyroid surgery has increased in utilization since 2004 but may have worse morbidity and mortality outcomes compared to open surgery.

The Learning Curve of Robotic Thyroid Surgery and the Avoidance of Temporary Hypoparathyroidism after Total Thyroidectomy and Concomitant Central Compartment Node Dissection: A Single Surgeon’s Experience

The aim of this study was to evaluate the learning curve of robotic thyroid surgery with regard to both operation time and temporary hypoparathyroidism using quantitative statistical analysis. A total of 194 patients who underwent total thyroidectomy and concomitant central compartment node dissection for papillary thyroid carcinoma by a single surgeon between December 2008 and September 2017 were enrolled. The learning curve for operation time was assessed using the cumulative sum (CUSUM) technique, and the number of procedures required to reduce the incidence of temporary hypoparathyroidism to less than 30% was determined using the CUSUM and risk-adjusted CUSUM (RA-CUSUM) techniques. The learning curve for operation time was divided into three phases: phase 1 (the initial learning period, 1st–19th cases), phase 2 (the challenging period, 20th–121st cases), and phase 3 (the competent phase, 122nd–194th cases). To reduce the incidence of temporary hypoparathyroidism to <30% required 119 cases, and after adjustment for potential risk factors by RA-CUSUM analysis this extended to 173 cases. Technical proficiency for robotic thyroid surgery with respect to the avoidance of surgical complications probably requires a longer learning period than that required for operation time.

Quantitative Assessment of the Learning Curve for Robotic Thyroid Surgery

With the increased utilization of robot thyroidectomy in recent years, surgical proficiency is the paramount consideration. However, there is no single perfect or ideal method for measuring surgical proficiency. In this study, we evaluated the learning curve of robotic thyroidectomy using various parameters. A total of 172 robotic total thyroidectomies were performed by a single surgeon between March 2014 and February 2018. Cumulative summation analysis revealed that it took 50 cases for the surgeon to significantly improve the operation time. Mean operation time was significantly shorter in the group that included the 51st to the 172nd case, than in the group that included only the first 50 cases (132.8 ± 27.7 min vs. 166.9 ± 29.5 min; p < 0.001). On the other hand, the surgeon was competent after the 75th case when postoperative transient hypoparathyroidism was used as the outcome measure. The incidence of hypoparathyroidism gradually decreased from 52.0%, for the first 75 cases, to 40.2% after the 76th case. These results indicated that the criteria used to assess proficiency greatly influenced the interpretation of the learning curve. Incorporation of the operation time, complications, and oncologic outcomes should be considered in learning curve assessment.