The Correlative Study Of MR Perfusion Weighted Imaging And Tumor Angiogenesis Together With Tumor Invasion In Astrocytoma

Objective: Angiogenesis and invasion complement each other to contribute to the progression of human astrocytoma. Vascular endothelial growth factor (VEGF) plays a pivotal role in inducing tumor angiogenesis and matrix metalloproteinases-9 (MMP-9) plays an important role in tumor invasion. We compared MR perfusion weighted imaging with MVD, VEGF and MMP-9 expression level in astrocytoma in order to investigate the correlation between MR perfusion weighted imaging and tumor angiogenesis together with invasion.Methods: We examined 42 patients with histologically verified astrocytoma and classified grade â… ,â…¡,â…¢,â…£.MR perfusion weighted imaging is performed preoperatively in all patients by using first-pass dynamic Gadolinium-enhanced SE-EPI perfusion sequence followed by conventional MRI. The perfusion original data were reestablished to get a color map of rCBV. The maximum rCBV ratios in the solid portion and peritumoral edema were calculated for each lesion in rCBV map by using contralateral normal white matter as reference. The expression levels of VEGF , MMP-9 were obtained after all specimens were immunostained postoperatively. The same immunohistochemical technique was also used to detect microvascular density (MVD) with CD34 related antigen monoclonal antibody. The correlation tests were used to determine the strength of the relationship between The maximum rCBV ratio in the solid portion and MVD together with VEGF expression levelsinall cases. The maximum rCBV ratios in the peritumoral edema of 20 specimens were compared with MMP-9 expression.Results: The maximum rCBV ratio in the solid portion correlated well with MVD among astrocytomas ( r = 0.6860, P<0.01). Significant difference (P<0.05) in the maximum rCBV ratio of the solid portion was found among astrocytomas according to different VEGF expression levels. The maximum rCBV ratio of the solid portion increased gradually with VEGF expression upgrading. There was significant difference (P<0.01) of MMP-9 labelling index among astrocytomas according to the maximum rCBV ratio of the peritumoral edema. In addition, the expression of VEGF and MMP-9 correlated well each other (P=0.003).Conclusion: The maximum rCBV ratio in the solid portion correlated well with MVD and VEGF expression levels among astrocytomas, and MR perfusion weighted imaging correlated with tumor angiogenesis. The maximum rCBV ratio of the peritumoral edema correlated well with MMP-9 expression. MR perfusion weighted imaging is feasible for evaluating the angiogenesis and invasion of astrocytomas. VEGF and MMP-9 correlate each other to promote the angiogenesis and invasion of astrocytomas.