Surgical quality determines the long-term survival superiority of right over left thoracic esophagectomy for localized esophageal squamous cell carcinoma patients: a real-world multicenter study

Objective: To compare the long-term overall survival (OS) of right versus left thoracic esophagectomy, and to evaluate whether surgical quality impacts comparison result. Background: Controversy regarding the optimal thoracic esophagectomy approach persists for esophageal squamous cell carcinoma (ESCC). No study has assessed the effect of surgical quality in comparison between right and left approaches. Methods: We consecutively recruited 5556 operable ESCC patients from two high-volume centers in China, of whom 2220 and 3336 received right and left thoracic esophagectomy, respectively. Cumulative sum was used to evaluate the learning curve for operation time of right approach, as the indicator of surgical proficiency. Results: With a median follow-up of 83.1 months, right approach, harvesting more lymph nodes, tended to have a better OS than left approach (Mean: 23.8 vs. 16.7 nodes; adjusted HR=0.93, 95% CI: 0.85-1.02). Subset analysis by the extent of lymphadenectomy demonstrated that right approach with adequate lymphadenectomy (≥ 15 nodes) resulted in statistically significant OS benefit compared with left approach (adjusted HR=0.86, 95% CI: 0.77-0.95), but not with limited lymphadenectomy. Subset analysis by surgical proficiency showed that proficient right approach conferred a better OS than left approach (adjusted HR=0.75, 95% CI: 0.64-0.88), but improficient right approach did not have such survival advantage. Conclusions: Surgical quality plays a crucial role in survival comparison between surgical procedures. Right thoracic esophagectomy performed with adequate lymphadenectomy and surgical proficiency, conferring more favorable survival than left approach, should be recommended as the preferred surgical procedure for localized ESCC.