Experimental research for the evaluation of radiotherapeutic response with 99Tcm-HL91 hypoxia imaging
DU Xue-mei1, ZHANG Yan-jun1, TAO Li1, JU Zai-shuang2, ZHANG Xin1, DENG Xiao-qin1
1. The First Hospital Affiliated to Dalian Medical University, Dalian Liaoning 116011, China;2. Department of Radiotherapy, Zhongshan Hospital to Dalian University, Dalian Liaoning 116011, China
Abstract：Objective: The aim of this study was to evaluate the radiotherapeutic response with 99Tcm-HL91 hypoxia imaging in mice bearing Hca-F25 tumor cells. Methods: All the mice bearing Hca-F25 tumor cells were divided into the irradiation group and the control group. The irradiation group were irradiated at a dose rate of 300MU/min with 6MeV linear accelerator; each irradiation dose was 15Gy. The control group weren’t irradiated. All the mice were injected intravenously with 0.1ml(37MBq) of 99Tcm-HL91 before radiotherapy, 3d and 5d after radiotherapy. Imaging was carried out 4 hours later and the tumor-to-normal ratio(T/NT) was calculated. Tumor length(A) and maximum vertical diameter(B) were measured before each imaging and caculated tumor volumes(mm3). At the end of the study, the weight and radioactivity of the tumors were measured. Percent of necrotic area(PNA) was calculated through hematoxylin-eosin(HE) staining of the tumor sections. Results: Tumors had good images. T/NT, Rv3, Rv5, tumor volumes and weights in the irradiation group were all obviously lower after irradiation than that in the control group(P<0.05), but PNA was on the opposition(P<0.05). T/NT before treatment was not correlated with Rv5 and PNA(P>0.05). Increased T/NT 3d after irradiation had positive correlation with Rv5, and negative correlation with PNA(P<0.05). Irradiation 3d later, the average Rv5 of uptake in the increased subgroup was more than that of uptake in the decreased subgroup, but the PNA was quite the reverse, there were significant differences(P<0.05). Conclusions: 99Tcm-HL91 image after irradiation was able to evaluate the radiotherapeutic response.
2007, Vol. 18 
