['This study aimed to determine the impact of prophylactic thoracic duct ligation on overall survival in resectable oesophageal cancer patients.', 'We conducted a retrospective analysis of 1804 patients with oesophageal cancers who underwent complete resection between December 1996 and December 2008. Based on the management of the thoracic duct during surgery, patients were classified into the following two groups: no prophylactic thoracic duct ligation group (NPLG, n = 815) and prophylactic thoracic duct ligation group (PLG, n = 989). Log-rank test was used to assess the survival differences between groups. Subgroup analysis and the Cox proportional hazards model were used to further determine the impact of thoracic duct ligation on overall survival.', 'The occurrence rate of postoperative chylothorax was comparable between NPLG and PLG (0.9% vs. 1.0%, p = 0.739). The median survival times for patients in the NPLG and PLG were 54.4 months (95% interval confidence, CI: 46.9-61.9) and 42.9 months (95% CI: 36.1-49.7), respectively (p = 0.002). The 2-year, 3-year, 5-year, and 10-year survival rates were 75.1%, 64.1%, 46.1%, and 35.1%, respectively, in the NPLG and 65.3%, 54.7%, 43.3%, and 30.9%, respectively, in the PLG, with a statistically significant difference between the groups (p = 0.002). Multivariate Cox regression analysis and subgroup analyses also demonstrated that thoracic duct ligation during oesophagectomy unfavorably impacted the overall survival of oesophageal cancer patients.'] Does prophylactic thoracic duct ligation have unfavorable impact on overall survival in patients with resectable oesophageal cancer?