A total of 361 patients with esophageal carcinoma who underwent esophagectomy at Sun Yatsen University Cancer Center between January 1997 and March 2004 were included in our study. There were 303 men and 58 women with ages ranging from 34 years to 82 years (median 58 years). The sites of primary tumor included: 32 in the upper thoracic esophagus, 211 at the middle thoracic esophagus, and 118 at the lower thoracic esophagus. As for the surgical approaches, 279 patients were via left thoracic approach and 82 via right thoracic approach. Lymphectomy extension included the conventional two fields. Postoperative staging were all stage III(pT3N1M0 in 320 patients; pT4N1M0 in 41 patients), and all were squamous carcinoma. There were 76 patients with highly differentiated, 166 with moderately differentiated, and 119 patients with poorly differentiated disease. Three patients received postoperative adjuvant radiochemotherapy, 48 patients received adjuvant radiotherapy, and 17 patients underwent adjuvant chemotherapy. The rest of the patients did not undergo adjuvant therapy.

Univariate analyses were performed for 15 indices of age, sex, tumor site, tumor length, surgical approach, surgical duration, perioperative blood transfusion, complications, ligation of the thoracic duct, depth of tumor infiltration (T staging), lymphnode metastasis, number of regions with lymphnode involvement, differentiation, adjuvant therapy, and other pathologic indices. Postoperative complications included those associated with surgery that required interventions (including cardiopulmonary complications, anastomosis leakage, wound infection, and other complications). The metastatic region was divided into the thoracic field(mediastinal field) and the abdominal field. The number of metastatic regions was defined as: 1 (either the thoracic or the abdominal region) and 2 (both the thoracic and abdominal regions). Tissue differentiations were categorized into groups of high, moderate, and low differentiations, and those with mixed degrees of differentiation were classified into the lower type. Adjuvant therapy included the intended adjuvant chemotherapy and radiotherapy.