Coexpression of cyclooxygenase-2 and vascular endothelial growth factor in gastrointestinal stromal tumor: possible relations to pathological parameters and clinical behavior.

Background/aims: Currently, the clinicopathological significance of coexpression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in gastrointestinal stromal tumors (GISTs) has not been fully described.

Methodology: The present study was designed to investigate the co-expression of the two markers and its significance in 54 patients with GIST by means of immunohistochemistry.

Results: We demonstrated that the expressions of COX-2 and VEGF were significantly higher in malignant GIST than those in benign and potentially malignant GIST (p<0.01). A significant correlation was found between COX-2 and VEGF expression. In addition, the expressions of COX-2 and VEGF were significantly correlated with pattern of tumor growth, the size of tumors, and the central necrosis of tumors (p<0.01 or p<0.05). Five-year survival rates were much lower in patterns with high expression of COX-2 and VEGF than those with low expression (p<0.01). Overexpression of COX-2 and VEGF in GIST may enhance the possibility of growth, invasion, and metastasis.

Conclusions: The levels of COX-2 and VEGF expression can be used as objective parameters in distinguishing benign from malignant, judging the malignant degree, and predicting the prognosis of patients with GIST.