Refractory chylothorax after esophagectomy caused by injured thoracic duct with a rare collateral branch: A case report

Background: Chylothorax is a rare but serious complication of esophagectomy that can be life threatening if not addressed in a timely fashion. Chylous leakage generally occurs in response to thoracic duct injury, and anatomical variations in thoracic duct structure can add to the risk of injury during esophageal surgery. Here, we report a rare occurrence of refractory chylothorax after esophagectomy and discuss the diagnostic strategy and aggressive surgical management for this condition, along with a review of the literature. Case presentation We report a 62-year-old man with refractory chylothorax that occurred after esophagectomy caused by a hidden collateral branch of the injured thoracic duct with a rare positional relationship to the injury site. The chylous fluid from the unrevealed right-sided duct drained into the injured left-sided thoracic duct via the collateral branch opposite the injury on the side wall of the thoracic duct and continually leaked out through the injury. After ligation of the hidden branch, the patient was cured and discharged 2 wk later. Conclusion This is a rare case of distal partial duplication of the thoracic duct, and anatomical variation of the thoracic duct can still lead to chylothorax even if its main trunk has been ligated prophylactically. Care must be taken to adequately ligate both trunks in cases of distal duplication as there is shared proximal trunk, and hidden collateral branches should be carefully explored at the same time.