Direct lymphatic drainage from the esophagus into the thoracic duct

The lymphatic vessels from around the esophagus which drain into the thoracic duct were identified macroscopically and histologically in 106 cadavers. Direct lymphatic drainage to the duct was macroscopically demonstrated by 84 vessels in 46 cases (43.4%). In 23 cases (19.8%), large collecting vessels arose from the thoracic esophagus and opened directly into the duct. In most of these cases (15/23) these lymphatic connections were found at the levels of the 1st-3rd or 6th-8th thoracic vertebrae. Histologic study revealed that two vessels originated from the fine lymphatic plexus in the esophageal adventita, which showed monocytic infiltration. In 11 of the 23 cases, an intercalated node was found along the thoracic duct. The results suggest that lymph drains rapidly into the systemic circulation via the thoracic duct. In view of the clinical applications in esophageal carcinoma, previous accounts of the extramural esophageal lymphatics concerned in direct drainage are discussed.