Long-term results after dissection of positive thoracic lymph nodes in patients with esophageal squamous cell carcinoma.

BACKGROUND: Although thoracic lymph node metastasis in patients with thoracic esophageal squamous cell carcinoma (SCC) has been reported to be a negative risk factor for long-term survival, only a few studies have evaluated the clinicopathologic difference between the impact of metastasis to the paraesophageal lymph nodes and to the nonparaesophageal lymph nodes. The purpose of this study was to evaluate surgical outcome after the clearance of metastatic thoracic lymph nodes. METHODS: Retrospectively reviewed were 164 consecutive patients with thoracic esophageal SCC who had not had preoperative treatment and underwent surgery from 1980 to 2005 and were found to have thoracic lymph node metastases. Of these patients, 83 underwent surgery from 1980 to 1994 and 81 from 1995 to 2005. Univariate and multivariate analyses were performed to evaluate the impact of nonparaesophageal lymph node metastasis on survival. RESULTS: Univariate analysis revealed that T3/T4 tumors and the presence of nonparaesophageal node metastases were associated with only a 20% overall five-year survival rate. The overall five-year survival for the most recent period was significantly better than for the former period (42% vs. 13%, p<0.01). Based on a multivariate analysis of prognostic impact of each nonparaesophageal node, the presence of metastatic subcarinal and/or posterior mediastinal nodes was an independent risk factor for reduced survival. CONCLUSION: Surgical outcome for patients with thoracic esophageal cancer and metastatic thoracic lymph nodes has improved during the last 25 years. Although postoperative chemotherapy might improve survival, the presence of T3/T4 tumors and/or metastatic nonparaesophageal nodes were unfavorable factors for survival.