Short- and long-term outcomes of prophylactic thoracic duct ligation during thoracoscopic-laparoscopic McKeown esophagectomy for cancer: a propensity score matching analysis

Background Chylothorax remains a challenging and potentially life-threatening postoperative complication after minimally invasive esophagectomy (MIE). The effect of intraoperative prophylactic thoracic duct ligation on preventing postoperative chylothorax still remains controversial. Moreover, the potential impact of thoracic duct ligation on long-term outcome after MIE has not been well established. Methods From September 2009 to July 2018, a total of 600 consecutive patients suffering from thoracic esophageal cancer who underwent thoracoscopic-laparoscopic McKeown esophagectomy in the Department of Thoracic surgery at Daping hospital were eligible. Among them, 559 patients received esophagectomy with preventive thoracic duct ligation and 41 patients did not. Propensity score matching (PSM) was performed to improve comparability between the two groups. Log-rank test was used to assess the survival differences between groups. Results Postoperative chylothorax occurred in five patients in the preservation group (PG) and in seven patients in the ligation group (LG) (12.2% vs. 1.3%,P = 0.001). The median age of the patients in the preservation group (PG) was 57.78 (range, 37-76) years, while the median age in the ligation group (LG) was 62.75 (range, 39-87) years. The PG had more patients with tumor located in middle thoracic esophagus and stage T3 than LG, 82.9% vs. 55.6%, 70.7% vs. 45.6%, respectively. After PSM (40 matched patients in PG and 134 in LG), there was no significant between-group difference with respect to age, tumor location, and T stage. The median survival times for patients in the PG and LG were 69.5 months (95% interval confidence, CI 54.6-84.3) and 65.2 months (95% CI 56.3-74.1), respectively (P = 0.977). The 5-year survival rates were comparable between PG and LG (54.9% vs. 54.4%,P = 0.977). Conclusion On the basis of the present results, routine thoracic duct ligation during minimally invasive McKeown esophagectomy for cancer is an effective and safe method for prevention of postoperative chylothorax, and does not exert unfavourable effect on long-term survival.