Background: The aim of this study was to clarify any relationship between the efficacy of postoperative adjuvant chemotherapy using oral fluoropyrimidines and the vascular endothelial growth factor (VEGF) expression in primary colorectal cancer tissues. Patients and Methods: The data on 379 patients with colorectal cancer at stage II or III, who underwent potentially curative resection with lymphadenectomy including mesenteric lymph nodes, were reviewed. Of these, 228 received postoperative administration of oral fluoropyrimidines (Chemotherapy Group), while other 151 patients underwent surgery alone (Surgery-alone Group). Immunostainig for VEGF was performed using surgical specimens from all 379 patients. Results: The positive ratio of VEGF expression was 47 % over all patients. The disease-free survival rate and overall survival rate in the Chemotherapy Group were significantly higher than those in the Surgery-alone Group. However, no significant difference in disease-free survival rate was found between the two groups for those with tumor positive for VEGF, tumor which involved mesenteric lymph nodes or nodes belonging to the internal iliac artery, or with tumor with lymphatic permeation or venous invasion. The positive ratio of VEGF expression was higher in those at stage III, and in those with severe lymphatic permeation. Conclusion: Postoperative adjuvant chemotherapy using oral fluoropyrimidines could not reduce the risk to recurrence for patients with a tumor positive for VEGF. Thus, combined use of molecular targeting therapy for VEGF with postoperative adjuvant chemotherapy using oral fluoropyrimidines would be ideal in tumors positive for VEGF in stage II or III colorectal cancer.
[Proc Amer Assoc Cancer Res, Volume 46, 2005]