Background: The purpose of the present study was to investigate the risk factors associated with lymph node metastatic recurrence in patients with N0 esophageal cancer after Ivor-Lewis esophagectomy based on the detection of Mucin 1 mRNA and vascular endothelial growth factor (VEGF) C mRNA.
Methods: The subjects were 82 patients with pN0 esophageal cancer who underwent Ivor-Lewis esophagectomy with two-field lymph node dissection from January 2001 to January 2005. A total of 501 lymph nodes obtained from these patients were re-evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) to detect mucin l (MUC1) mRNA; VEGF-C mRNA was also detected in esophageal cancer issues by RT-PCR. 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, the log-rank test was performed to compare the recurrence rate, and Cox regression multivariate analysis was performed to determine independent prognostic factors.
Results: MUC1 mRNA was detected in 29 lymph nodes from 23 patients, which accounted for 5.79% of all the 501 lymph nodes and 28.05% of all 82 patients, respectively. Vascular endothelial growth factor C mRNA was identified in esophageal cancer issues from 42 (51.22%) patients. The overall 3- and 5-year survival rates of 82 patients were 78.0 and 51.2%, respectively. First recurrence exhibiting lymph nodal metastasis was recognized in 37 patients (45.1%) in the first 3 years after operation. The lymph node metastatic rate in patients in the first 3 years after operation was significantly associated with T status (p < 0.05) and the lymph node metastatic rate of the patients with LNMM was significantly higher than that of the patients without LNMM (p < 0.01). The lymph node metastatic rate of the patients with VEGF-C mRNA expression in esophageal cancer tissues was significantly higher than that of the patients without VEGF-C mRNA expression (p < 0.01).The results of multivariate analysis confirmed that VEGF-C mRNA expression in esophageal cancer tissues, LNMM, and T status in patients with N0 esophageal cancer were independent relevant factors for 3-year lymph node metastatic recurrence after Ivor-Lewis esophagectomy.
Conclusions: Vascular endothelial growth factor C mRNA expression in esophageal cancer tissues, LNMM, and T status in patients with N0 esophageal cancer 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.