The Experiment Of Changes Of Blood Supply And Proliferation After Radiotherapy In VX2 Limb Soft-tissue Tumor

Objective:To probe changes of blood supply and proliferation after radiotherapy in VX2 limb soft-tissue tumor by three-dimensional power doppler angiography(3D-PDA),histologic and immune-histochemically.Methods:Establish VX2 limb soft-tissue tumor model. Animals were randomly divided into three groups: the control group,intensity modulated radiotherapy(IMRT) group, volumetric modulated arc therapy(VMAT) group, 3D-PDA was performed on the first week after radiation, vascularization index(VI), flow index(FI) and vascularization flow index(VFI) were calculated,then HE staining was performed, micro vessel density(MVD)and expression of Ki-67 were assessed immune-histoehemically. Results:VI, FI and VFI showed significant differences among three groups(P <0.05), IMRT and VMAT group was lower than control group. Ki-67 proliferation index in IMRT and VMAT group was lower than control group(P <0.05).MVD in IMRT and VMAT group was lower than control group(P <0.05). Ultrasound parameters VI was positive correlated with MVD(r=0.91, P <0.05).MVD was positive correlated with Ki-67(r=0.95, P<0.05). Conclusion :Radiotherapy can significantly inhibit tumor angiogenesis and proliferation.3D-PDA can evaluate radiotherapeutic effects in a stereo blood supply manner in VX2 limb soft-tissue tumor.