Impact of Lymph-Node Metastasis Site in Patients With Thoracic Esophageal Cancer

Background and Objectives: We retrospectively compared surgical outcomes between patients with intra-thoracic and extra-thoracic (cervical and abdominal) lymph-node metastasis. Methods: The study population comprised 96 patients with lymph-node metastasis who had undergone curative esophagectomy for thoracic esophageal cancer. The patients were grouped according to whether the site of lymph-node metastasis was intra-thoracic, extra-thoracic, or both intra-thoracic and extra-thoracic. The patient characteristics, survival time, and prognostic factors were compared. Results: The most significant difference in disease-specific survival was detected at a threshold value of four metastatic lymph nodes. Lymph-node metastasis was observed at intra-thoracic sites in 41 patients, at extra-thoracic sites in 20 patients, and at both intra-thoracic and extra-thoracic sites in 35 patients. Intra-thoracic lymph-node metastasis was frequently observed in patients with middle and upper thoracic esophageal cancer. There was no difference in the number of metastatic lymph nodes between patients with intra-thoracic and extra-thoracic lymph-node metastasis. Multivariate analysis revealed that the number of metastatic lymph nodes was an independent prognostic factor, whereas the site of metastatic lymph nodes was not. Conclusions: These findings suggest that the surgical outcomes in patients with thoracic esophageal cancer depend on the number, but not the site, of metastatic lymph nodes after curative esophagectomy. J. Surg. Oncol. 2010;101:36-42. (C) 2009 Wiley-Liss, Inc.