Cyclooxygenase-2 expression after preoperative chemoradiotherapy correlates with more frequent esophageal cancer recurrence

AIM： To investigate the relationship between cycloo- xygenase-2 （COX-2）, and vascular endothelial growth factor （VEGF）, and to determine the clinical significance of this relationship in esophageal cancer patients undergoing chemoradiotherapy （CRT）. METHODS： Immunohistochemical staining was used to evaluate COX-2 and VEGF expression in 40 patients with histologically-confirmed esophageal squamous carcinoma （ESCC） who were undergoing preoperative CRT. RESULTS： Fourteen out of 40 ESCC patients showed a pathological complete response （CR） after CRT. COX-2 and VEGF protein expressions were observed in the cytoplasm of 17 and 13 tumors, respectively, with null expression in 9 and 13 tumors, respectively. COX-2 expression was strongly correlated with VEGF expression （P 〈 0.05）. There were also significant associations between COX-2 expression, tumor recurrence, and lymph-node involvement （P = 0.0277 and P = 0.0095, respectively）. COX-2 expression and VEGF expression had significant prognostic value for disease-free survival （log-rank test; P = 0.0073 and P = 0.0341, respectively）, but not for overall survival, as assessed by univariate analysis. expression correlates with VEGF expression and might be a useful prognostic factor for more frequent tumor recurrence in ESCC patients undergoing neoadjuvant CRT. These findings support the use of anti-angiogenic COX-2 inhibitors in the treatment of ESCC.