Dynamic contrast-enhanced magnetic resonance perfusion weighted imaging in astrocytomas： correlation with histopathology and immunohistochemistry

Objective： To investigate magnetic resonance perfusion weighted imaging and its relationship with the grading and the expression of vascular endothelial growth factor （VEGF） and angiogenesis in astrocytomas. Methods： A collection of 34 patients with astrocytomas proved by surgery and pathology were examined by magnetic resonance imaging（MRI）, with 26 cases of grade Ⅰ-Ⅱ （low-grade） and 8 cases of grade Ⅲ-Ⅳ （high-grade）. MR perfusion images were obtained with spin-echo echo planar imaging （SE-EPI） techniques. Expression of VEGF was examined by immunohistochemical method of streptavidin-biotin-peroxidase（SP）. The vascular development was measured by micro-vascular density （MVD） which was immunostained with anti-factor Ⅷ-related antigen monoclonal antibody. Results： Both of the expression of VEGF and the angiogenesis in 34 cases of astrocytomas were significantly correlated to the maximum relative cerebral blood volume （Max rCBV） （r=0.604, P〈0.001; r=0.625, P〈0.001, respectively）. The Max rCBV and the expression of VEGF, MVD in high-grade astrocytomas were significantly higher than that of in low-grade astrocytomas （t=3.0, P=0.017; t=7.08, P=0.01; t=3.37, P=0.011, respectively）. Conclusion： MR perfusion weighted imaging might be a valuable method in in vivo study of the angiogenesis of astrocytomas and evaluating their malignant degree and prognosis.

Dynamic contrast-enhanced magnetic resonance perfusion weighted imaging in astrocytomas: correlation with histopathology and immunohistochemistry