Microvessel Density (MVD) and Vascular Endothelial Growth Factor (VEGF) As Predictors of Gastrointestinal Stromal Tumors Behavior,ANAN FATHY
Abstract
Background: The prediction of gastrointestinal stromal tumors (GISTs) behavior is still difficult in spite of suggestion of several histopathologic criteria.
Objective: This study was designed to investigate the potential role of angiogenesis in prediction of GISTs behavior.
Material and Methods: An immunohistochemical study using monocolonal antibodies for c-kit (CD 117), VEGF and CD31 was performed on paraffin sections of 20 specimens of GISTs cases. They were collected from Pathology Depart-ments of Cairo University Hospital and Ain-Shams University Hospital in the period between 1990-2007. Microvessel Density (MVD) was evaluated via immunohistochemical staining for CD31.
Results: All cases demonstrated immunoreactivity for c-kit. On the other hand 85% (17/20) of cases showed VEGF immunoreactivity. Grade 2 intensity of VEGF immunostaining was noticed more in intestinal GISTs (5/6; 83%) and in tumors >!5cm in diameter (5/9; 56%). Also it was correlated with GIST with high mitotic activity ³5/50HPF (7/7; 100%) and high risk grade (4/5; 80%) tumors. Moreover, high VEGF intensity of staining was associated with high MVD (4/8; 50%). In addition, a correlation between high MVD and intestinal GISTs was found in (4/6; 67%) of cases and in tumors with diameter >!5cm (6/9; 67%). High MVD was similarly associated with high mitosis ³5/50 HPF (5/7; 71%) and with high risk grade GISTs (4/5; 80%).
Conclusion: High MVD is associated with VEGF over expression and other poor prognostic indicators of GISTs. So assessment of GISTs angiogenesis via both measuring MVD and studying VEGF expression can predict GIST prognosis and encourage anti angiogenesis therapy for treatment of GISTs cases.