Prognostic value of the number of negative lymph nodes in esophageal carcinoma without lymphatic metastasis

BACKGROUND: The impact of the number of negative lymph nodes (LNs) on survival in patients with esophageal cancer remains a controversial issue. This study investigated the association between the number of resected LNs and the prognosis of patients with node‐negative esophageal carcinoma. METHODS: A retrospective review was performed of the data of 429 patients who underwent esophagectomy with modern two‐field lymphadenectomy for the treatment of esophageal cancer between January 1998 and December 2008. Histopathology showed no LN involvement in the patient sample. The prognostic impact of the number of negative LNs and the clinicopathological factors were analyzed. RESULTS: The overall median survival time and the one, three, and five‐year overall survival rates were 63.0 months and 78.5%, 64.0%, and 51.2%, respectively. Survival analysis confirmed that the number of negative LNs and the depth of tumor invasion were independent prognostic factors. Patients with a high number of negative LNs had a better overall survival rate than patients with a low number of negative LNs (P < 0.001). Patients with dissected LNs > 14 for pT1 tumors (P < 0.001) and > 19 for pT2–3 tumors (P < 0.001 and P = 0.001, respectively) had better long‐term survival outcomes. CONCLUSIONS: The number of negative LNs is an independent prognostic factor for node‐negative esophageal carcinoma. Extended LN dissection is recommended to improve the survival of patients with node‐negative esophageal carcinoma.