Evaluating The Sensitization Effect Of 5-ALA On A45 Treating VX2 Rabbit Liver Cancer Model By IVIM-DWI

ObjectiveApplying intravoxel incoherent motion diffusion weighted imaging(IVIM-DWI)to monitor the changes of D value,D*value and f value in VX2 rabbit tumors treated with A45 combined with 5-ALA,and to explore the effect of 5-ALA on the efficacy of A45 treatment.Materials and Methods40 VX2 rabbit liver cancer models were selected and randomly divided into 4 groups.? group:A45+5+ALA therapeutic group;? group:A45 therapeutic group;?group:5-ALA group;? group:blank control group,10 in each group.? group was undergone A45 radiotherapy 4h after received intraperitoneal injection of photosensitizer 5-ALA(1ml/kg,VX2 rabbits were kept in dark place immediately after injection),with a single dose of radiation of 6Gy;? group was undergone A45 radiotherapy alone,with a single dose of radiation of 6Gy;? group was undergone intraperitoneal injection of photosensitizer 5-ALA(1ml/kg,VX2 rabbits were kept in dark place immediately after injection);? group was not undergone any therapy.Four groups of animals received MR scanning Id prior to therapy,? week and 2 week after therapy.The sequences were separately axial view T1W1,FS-T2W1,coronal view and axial view IVIM;six values b=0,50,100,200,400,800s/mm were adopted,TR=70.0ms,TE=88ms.FOV 240mm × 240mm × 240mm,layer thickness 4mm,layer spacing 1.5mm.The images acquired were postprocessed via MRToolbox software,four groups images pure diffusion coefficient(D),pseudo-diffusion coefficient(D*)and filling fraction(f)were tested,and D,D*values differences in different groups were compared,and IVIM-DWI sequence was analyzed for its value in efficacy assessment of A45 combined photosensitizer therapy.SPSS 22.0 software was applied to do statistical analysis to related data.The result P<0.05 was considered to be statistical significance.ResultsD,D*and f values prior therapy in each therapeutic group do not have statistical significance(p<0.005).After 1 week,D,D*and f values all have statistical significance(P<0.01)between ? and ? group,I and ? group,? and ? group;neither D,D*and f values between ? group and IV group have statistical significance(P>0.05).2 weeks after therapy,D,D*and f values all have statistical significance(P<0.01)between ? and ? group,? and ? group,? and ? group;neither D,D*and f values between ? group and ? group have statistical significance(P>0.05).1 week after therapy,in ? group and ? group,D value and f value increased,D*value decreased;2 weeks after therapy,in both groups,D value continued to increase,D*value continued to decreased,and f value decreased,but its change degree was more significant compared with ? group and ? group;1 week and 2 weeks after therapy,in ? group and IV group,both D*value and f value increased,D value slightly decreased,and the general change degree in both groups was roughly similar.ConclusionA45 radiotherapy has therapeutic effect towards VX2 rabbit liver cancer model,combined with 5-ALA the effect of A45 radiotherapy can be increased,that is sensibilization;no significant effect is received in 5-ALA treating VX2 rabbit liver cancer model alone.