Learning Curve and Associated Prognosis Of Minimally Invasive McKeown Esophagectomy

Background: The implementation of McKeown minimally invasive esophagectomy (MIE) is associated with a steep learning curve. However, there is no consensus on the number of cases required before effective and safe McKeown MIE can be achieved.

Methods: Data on consecutive patients with esophageal carcinoma who underwent esophagectomy performed by a single surgeon in the Department of Thoracic Surgery at Daping Hospital in Chongqing, China from September 2009 to June 2019 were collected. The cumulative sum learning curve was plotted on the basis of the learning associated parameters. Propensity score matching was used to reduce selection bias from confounding factors. The Kaplan-Meier method was used to assess the survival differences.

Results: The learning curve was divided into the ascending period (cases 1-197), the plateau period (198-314), and the descending period (315-onward). After 197 cases, significant improvements in operative time (300 minutes vs 210minutes; P < .001), retrieved lymph nodes (17 vs 20; P = .004), hospital length of stay (18 days vs 13 days; P = .001), major postoperative complications (38.6% vs 32.5%; P < .001), vocal cord palsy (6.1% vs 0.9%; P = .04), and pulmonary complications (31.5% vs 17.1%; P = .005) were observed. In addition, after 314 cases, significant decreases in blood loss (200 mL vs 100 mL; P < .001), anastomotic leak (24.8% vs 14.8%; P = .02), and chylothorax (4.3% vs 0%; P = .001) were observed. After propensity score matching, the overall and disease-free survival rates were significantly improved during the experienced period (P = .02 and .03, respectively).

Conclusions: The initial learning phase of McKeown MIE consisted of 197 procedures in 51 months. Moreover, the surgeon's experience did have a direct impact on the long-term outcomes in patients with esophageal carcinoma.