Experimental Study On Comparing Of CT And Pathological Of Residual Tumor Of Hepatic VX₂ Carcinoma In Rabbit After RFA

ObjectiveReveal and evaluate bionomics and CT imageology characteristic of residualtumor on the cell molecular level after RFA, according to RFA in treatment of hepaticVX₂ carcinoma rabbit model, comparing appearance between CT image and pathologyof different stage of residual tumor, provided evidence for effective of RFA intreatment of hepatoma.MethodsResuscitate frozen VX₂ tumor cell, and then implant them in the wall muscles oftwo rabbit hind legs. Bearing cancer rabbit were made 3weeks later. The eugonic tissueat the margin of tumor was cut into pieces which had Similar size (1mm×1mm×1mm).45 healthy rabbits, made for the hepatic VX₂ carcinoma model by the way oflaparotomy, Implant the tumor in the liver directly, most of them were implant in leftliver, hepatic VX₂ carcinoma model was made 3 weeks later, and then them weredivided randomly into 3 groups, 15 rabbits per group, group A, control group, no RFA.Group B and C were made into the group of residual tumor and complete ablation bythe damage radius(the radio of group B is 2/3 maximum tumor radius, the radio ofgroup C is maximum tumor radius +0.5cm). Have CT plain scan and enhancementscan at the end of 2 days,7 days,14 days, then review the pathological appearanceand PCNA index number in 5 rabbits randomly every group. Results1. CT appearance of residual tumor and inflammation after RFA, CT plain scan,The residual tumor appear low density focus, The inflammation couldn't be found inplain scan. CT enhancement scan, Both of them showed marginal enhancement band.The CT number of enhancement band of residual tumor the in the 2nd day after RFAwas lower than them in 7th day and 14th day, the difference is obvious. Theinflammation not only showed marginal enhancement band, but also ento-ectadattenuated enhancement in the liver tissue, which is most obvious at the 2nd day andweakened gradually and disappeared 2 weeks later.2. The PCNA index of 2nd, 7th of group B was lower than group A, the differencehad statistical significance. The PCNA index of group B rise again, which had noobvious difference than group A.3. The pulmonary metastasis rate of 3 groups were all 60% in the 2nd day. In the7th day, the pulmonary metastasis rate of group A was 100%, which were 80% and 60%in group B and C, in the 14th day, the pulmonary metastasis rate of group A was 100%,which were 100% and 60% in group B and C, the difference were different obviously.4. The complete ablation had no residual tumor in the 2 weeks after RFA, and lotsof fibrous tissue round the focus of infection could be seen in group B and C, whichinhibited the growth and invasion of tumor. So we called it the fibro barrier effect afterRFA.Conclusion1. We can't differentiate exactly the residual tumor and inflammatory reactionzone through CT enhancement scanning after RFA in 1 week, and after 2 weeks, wecan consider that the marginal strengthening in the side of necrotic focus is residualtumor.2. RFA have the inhibitory action to the proliferation of residual tumor on earlystage.3. RFA not only kill tumor cell, but also inhabit the invasion and metastasis of tumor.