肝动脉血流对兔VX2肝脏肿瘤冷冻效果的影响

Effect of hepatic blood flow alteration on the therapeutic effect of cryoablation in VX2 hepatic tumor rabbit： an experimental study

目的通过建立兔VX2肝脏肿瘤模型，观察肝动脉血流对氩氦超低温冷冻消融治疗效果的影响。方法30只成功建立VX2肝脏肿瘤模型的实验兔，于肿瘤种植后第14天，用数字表法随机等分为3组。调整肝动脉血流，肝动脉完全阻断组为A组，部分阻断组为B组，正常对照组为C组。行CT平扫和灌注扫描，计算各组肿瘤组织血流量（BF）、血容量（BV），采用方差分析法分析3组参数之间的差别。然后行氩氦冷冻治疗，术后即刻处死实验兔，取出肝脏。取肝脏肿瘤冷冻区及其周围组织分别进行氯化硝基四氮唑蓝（TTC）及四甲基偶氮唑（MTT）染色，观察大体及镜下病理改变。结果（1）肿瘤种植后第14天，A组肿瘤组织的BF和BV值分别为（7．23±2．15）ml·100g^-1·min^1和（1．63±0．52）ml／100g；B组分别为（32．65±6．12）ml·100g^-1·min^-1和（9．32±2．63）ml／100g；C组分别为（61．34±12．15）ml·100g^-1·min^-1和（17．51±3．14）ml／100g，3组间差异均有统计学意义（F值分别为452．16和421．33，P〈0．01）。（2）TTC染色显示，肿瘤组织平均最大冷冻直径A组为（2．3±0．3）cm，B组为（1．5±0．2）cm，C组为（0.8±0.1）cm，3组差异有统计学意义（F值为315．32，P〈0.01）。（3）MTT染色可见界限清楚的冷冻区、交界带及周围正常染色区；在未结扎肝动脉的C组可见无染色的冷冻区内部分血管周围组织染色阳性。结论减少肝动脉血流可明显提高肝癌冷冻治疗的效果。

Objective To investigate the effect of alteration of blood flow in the hepatic artery on the therapeutic effect of cryoablation in VX2 hepatic tumor rabbit model. Methods Thirty rabbits with VX2 hepatic tumor were divided into three groups according to hepatic artery blood flow： complete occlusion of the hepatic artery（ group A） , partial occlusion of the hepatic artery （group B） , and no occlusion of the hepatic artery （group C）. With conventional CT scan and perfusion scan, the values of blood flow（BF） and blood volume（BV） of VX2 tumor were computed and the differences among the three groups were analyzed. After cryoablation, the animals were euthanized and the livers were removed. The hepatic tissue from the cryoablation area and surrounding area underwent both methyl thiazolyl tetrazolium （MTT） diaphorase staining and triphenyl tetrazolium chloride （TTC） staining. The gross pathology and histopathological changes were observed. Results （ 1 ） The BF and BV in the three groups were ： （ 7.23 ± 2. 15 ） ml · 100g^-1· min^-1 and （1.63 ±0.52） ml/100 g in group A;（32.65±6.12） ml · 100 g^-1 · min^-1 and （9.32±2.63） mL/100 g in group B; （61.34 ± 12.15） ml · 100 g^-1· min^-1 and （17.51 ± 3. 14） mL/100 g in group C, respectively. There were significant differences among the three groups in the BF and BV （ F value was 452. 16 and 421.33 in the BF and BV, respectively, P〈0.01）;（2） The maximum diameter of cryoablation-induced necrosis was （ 2. 3 ± 0. 3 ） cm in group A, （ 1.5 ± 0. 2 ） cm in group B, and （ 0. 8 ± 0. 1 ） cm in group C, respectively. The difference was significant among the groups （F value was 315.32,P 〈0.01）. （3）There were well-defined frozen areas, bordering areas and normal surrounding areas in MTT staining. In group C, positive staining around some blood vessels could be seen.Conclusion Alteration of the blood flow in the hepetatic artery can affect the cryoablation efficacy. With the decrease of hepatic artery blood flow, the efficacy of cryoablation on liver tumor increased.