Clinical study on lymph node metastatic recurrence in patients with N0 esophageal squamous cell cancer

Esophageal squamous cell cancer (ESCC) is one of the most common malignancies treated by thoracic surgeons. It is aggressive and generally associated with a poor prognosis. One of the most important prognostic factors is the presence of the lymph node metastasis (LNM). The purpose of the present study was to investigate the risk factor with lymph node metastatic recurrence in patients with N0 esophageal squamous cancer after Ivor Lewis esophagectomy based on the detection of mucin1 (MUC1) mRNA. The subjects were 82 patients with pN0 ESCC who underwent Ivor Lewis esophagectomy with two-field lymph node dissection from January 2001 to January 2005. All lymph nodes (501 stations) obtained from these patients were reevaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) to detect MUC1mRNA. The diagnosis of lymph node micrometastasis (LNMM) was based on the detection of MUC1 mRNA. The Kaplan-Meier method was used to calculate the survival rate and lymph nodal metastatic rate. Log-rank test was performed to compare the recurrence rate, and Cox regression multivariate analysis was performed to determine independent prognostic factors. The overall 3-year survival rates of 82 patients were 78.0%, and the first recurrence exhibiting lymph nodal metastasis was recognized in 37 patients (45.1%) in the first 3 years after operation. Lymph node metastatic rate in patients in the first 3 years after operation was significantly associated with the T status (P < 0.05). MUC1 mRNA was identified in at least one lymph node station from 23 (28.1%) patients. Also, lymph node metastatic rate of the patients with LNMM was significantly higher than that of the patients without LNMM (P < 0.01).The results of multivariate analysis confirmed that LNMM and T status in patients with N0 ESCC were independent risk factors for 3-year lymph node metastatic recurrence after Ivor Lewis esophagectomy. Adjunctive therapy might be beneficial in controlling the locoregional recurrence and elevated healing rates for certain patients.