Study On The Correlation Between CT Features And Microvessel Density And Expression Of Vascular Endothelial Growth Factor In Astrocytoma

Objective To study the correlation among the CT features and microvessel density (MVD) and expression of vascular endothelial growth factor (VEGF) in human astrocytoma, investigate the ability of CT assessing tumor neovascularization , understand deeply the significance of CT features of astrocytoma and obtain more information for its diagnosis , selection of treatment decision and prognosis by CT. Methods The MVD and expression of VEGF were examined by means of SP immunohistochemical technique in 52 cases of astrocytoma proved by pathology. All patients were examined by normal and contrast-enhanced CT scanning, and had never been treated with non-operative management before operation, such as radiotherapy^ chemotherapy and so on. Microvessel counting and calculation of VEGF expression percentage were observed at 400 x magnification under the same standard respectively. The correlation of tumor grade with MVD and expression of VEGF was analyzed. The CT manifestations of pre-operation, including tumor density, degree of enhancement, enhancement morphology, calcification, necrosis, cysts, border, peritumoral edema, mass effect, were analyzed together with their relation to MVD and expression of VEGF. The astrocytoma was classified into type A, typeB and type C according to its CT manifestations. Studying the relationship between CT types and the degree of tumor angiogenesis. Postoperative recurrence was also compared with MVD and expression of VEGF. Pearson's correlation, analysis of variance and t-test were applied in statistical analyzing. Results ?The pathologic grading of astrocytoma was positively correlated with its MVD and expression of VEGF, especially in grade I ~II and grade IH~ IV(P<0.01). There were no statistical correlation between I and II , or between III and IV (p>0.05).There was a close positive correlation between MVD and expression of VEGF(r=0.86). (2)MVD and expression of VEGF were significantly correlated with tumor heterogeneity of density, enhancement morphology, degree of enhancement > necrosis > calcification -, peritumoral edema > mass effect -. border(P<0.05), but not with the formation of tumor cysts(P>0.05). The MVD and expression of VEGF in high density group had no correlation with heterogeneous density group (PO.05) .〤omprehensive type A (n=23) had lower MVD and expression of VEGF than those of type B (n=14) and C(n=15), (PO.01). The MVD and expression of VEGF in type C were higher than those of type A and B (PO.01). There was the largest coefficient of correlation between the comprehensive types of CT features and the degree of angiogenesis (r=0.81). (4) MVD and expression of VEGF were significantly higher in recurrence group than those of no recurrence group. (PO.01). MVD and expression of VEGF (29.5 + 3.3, 83.7 + 11.7, respectively) in five cases with heterotopic dissemination after operation were higher than those of other cases(P<0.05). Conclusion: ?Theseresults indicate that the CT features of astrocytoma , including enhancement, calcification, necrosis, border, edema, mass effect, and recurrence are significantly related to MVD and expression of VEGF. (2) As compared with single CT characteristic, comprehensive types of CT features can predicate tumor neovascularization more accurately. (3) Analyzing the relationship between CT features and tumor neovascularization of astrocytoma, we can further understand the CT characteristic and get more information for its diagnosis, selection ofmanagement and prognosis.