The influence of thoracic duct ligation on long-term survival of patients with esophageal cancer: a propensity score-matched analysis

BACKGROUND: Ligation of the thoracic duct (LTD) is known to be a useful way to prevent postoperative chylothorax, but its impact on long-term survival is rare to be assessed. METHODS: Data from 609 patients with esophageal cancer who underwent esophagectomy from September, 2012, to January, 2014, were retrospectively collected. The study cohort was classified into two groups: the thoracic duct ligation group (LG) and the non-ligation group (NLG). Propensity score matching (PSM) was performed to control confounding factors between the two groups. Postoperative complications and length of stay were compared between the two groups. Overall survival was estimated using the Kaplan-Meier method, and compared using the log-rank test. Independent prognostic factors were determined using Cox regression analysis. RESULTS: After PSM, there were 185 patients in each of the two groups. LTD had no significant impact on chylothorax, anastomotic leak, recurrent nerve palsy, pneumonia and length of stay (P>0.05). The 1-, 3- and 5-year survival rates were 87.0%, 64.1%, and 50.9% in the LG, respectively, compared to 85.4%, 59.9%, and 42.3%, respectively, in the NLG. The differences between the 2 groups were not statistically significant (P=0.156). In the multivariable analysis, LTD was not an independent prognostic factor, neither before nor after PSM. CONCLUSIONS: Our study demonstrated that LTD had no significant impact on postoperative complications or long-term survival in patients with esophageal cancer.