OBJECTIVE Postoperative chylothorax remains an uncommon but potentially life-threatening complication of esophagectomy for cancer, and the ideal management is still controversial. The aim of the study was to compare the outcomes of patients treated nonoperatively with those of patients promptly undergoing reoperation. METHODS From 1980 to 1998, 1787 esophagectomies for esophageal or cardia cancer were performed, and 19 (1.1%) patients had postoperative chylothorax. We analyzed type of operation, surgical approach, delay of diagnosis of chylothorax, daily chest tube output, type of management, major complications, death, hospital stay, and final outcome. RESULTS Of the 19 patients with chylothorax, 11 were initially managed nonoperatively (group A): 4 (36%) patients had spontaneous resolution of chylothorax, and the other 7 required reoperation for the persistence of a high-volume output. There were three infectious complications and one postoperative death in this group. No reliable predictive criteria of successful versus unsuccessful nonoperative management could be found. The 8 most recent patients underwent early reoperation (group B). All patients recovered, and no major complications possibly related to chylothorax or hospital deaths were observed. They were discharged after a median of 22 days (range, 12-85 days) compared with a median of 36 days (range, 21-64 days) for patients of group A. CONCLUSIONS Early thoracic duct ligation is the treatment of choice for chylothorax occurring after esophagectomy. Reoperation should be performed immediately after the diagnosis is made to avoid the complications related to nutritional and immunologic depletion caused by prolonged nonoperative treatment.