Analysis Of The Dose And Local Control Of CT-guided Radioactive ¹²⁵I Seed Implantation In The Treatment Of Liver Cancer

Objective:To observe the effect of CT-guided radioactive ¹²⁵I seed implantation in the treatment of hepatocellular carcinoma,and to analyzethe relationship between the dose and the local control.Methods:From January 2015 to December 2017,27 patients with hepatocellular carcinoma treated with ¹²⁵Iseeds under CT guidance and 45 surgical lesions were selected as the subjects of the study.The experimental methods were divided into three stages:pre-operation,during-operation and post-operation.Before the experiment,patients were tested with enhanced CT to define the location,size of the lesion and the internal relationship between the surrounding organs.Based on the obtained image information,the preoperative plan was determined,the target area was delineated,the prescription dose and particle activity were set,the source was planned,and the preoperative preparation was made.During the operation,CT scan was performed immediately after implantation of radioactive ¹²⁵I seeds,and the operation was performed under local anesthesia.Close observation was made after operation,and the patients were re-examined with CT.The dose was verified.The quality of parameters such as D90,D100,V100,V150,D200 and DVH were evaluated.The patients’abdomen was scanned by enhanced CT one month after operation and every three months,and the clinical therapeutic effect and side effects were analyzed.The log-rank test and Cox regression model were used for the univariate and multivarrateanalyses,respectively.Results:Of the 27 patients,19 died and 8 survived,with a survival rate of 29.6%.The median follow-up time was 15 months.The median OS period was 15.3（95%CI was 12.8-18.6）months,and the median LC time was 9.5（95%CI was 5.9-12.7）months.The median tumor volume（GTV）was 14.9cc（2.1-199.8cc）;the median number of needles was 4（1-18）;the median number of particles was 23（4-139）;and the median particle activity was 3.01-107Bq.D90 is（119.5+24.8）Gy,D100 is（54.6+14.2）Gy,V100 is（89.9+1.2）%,V150 is（62.2+7.1）%,V150 is（51.8+3.9）%.There existed the statistical difference in the therapeutic effect of different groups of QA（P<0.05）.PVTT was very clear before operation,but the tumor thrombus gradually decreased and the width of portal vein was widened one month and three months after operation.There was an intrinsic correlation between D90 and LC time（F=9.776,P=0.000）.There was a temporal correlation between V100 and OS（F=8.635,P=0.050）.According to multi-factor analysis showed thatthere was an intrinsic correlation between D90 and LC time（F=8.428,P=0.017）,a temporal correlation between V100 and OS time（F=8.835,P=0.031）,a temporal correlation between V100 and LC time（F=7.460,P=0.047）,an intrinsic correlation between D90 and OS time（F=7.931,P=0.044）.After operation,AFP,CEA,CA199,ALT,AST,gamma-GT,DBIL,TBIL and PA all decreased（P<0.05）.The patients with grade 1 and grade 2 side effects were7.4%（2/27）,and those with grade 3 or above were 3.7%（1/27）.Conclusion:In the treatment of hepatocellular carcinoma using CT-guided radioactive¹²⁵I seed implantation,the D90 and V100 were related to LC time and OS time respectively.The D90 and V100 values in the postoperative verification plan may predict treatment outcomes in patients.