兔VX_2肝癌模型的建立及超声观察

Establishment of rabbit model bearing VX _2 liver tumor and monitoring with ultrasound technique

目的比较不同种植方法兔VX2肝癌模型的生长特点,评价琼脂糖针道内注射减少肿瘤异位种植的效果及超声观测肿瘤生长的价值.方法 45只新西兰白兔随机分为3组,每组15只.第1组,将VX2瘤组织块悬液(约含107～108个瘤细胞/ml) 超声引导下注入兔肝左叶,拔针时压迫针道 3 min;第2组,注射方法同1组,拔针前注入 0.2 ml加热的琼脂糖封堵针道;第3组,将VX2瘤组织块 (1 mm3大小3块),经剖腹途径埋植于兔肝左叶.比较不同植瘤方式肿瘤的生长特点,超声监测肿瘤生长并与病理检查进行相关性分析.结果①三组植瘤成功率分别为 20.0%(3/15)、80.0%(12/15)和 73.3%(11/15),肿瘤的异位种植率分别为 80.0%(12/15)、20.0%(3/15)和 15.4%(2/13),第1组与2、3组相比,差异有显著性意义;②肿瘤超声表现为等回声、低回声及略高回声,以等回声居多,周围可见声晕;彩色多普勒和能量多普勒均可检出血流信号;③肿瘤与肝实质无明显边界,可见多个核分裂相;④超声与病理下测定肿瘤的最大切面直径的相关系数r=0.946,P=0.000.结论超声引导下成功建立了兔VX2肝癌模型,瘤组织块悬液种植加琼脂糖封堵针道方式可有效减少肿瘤的异位种植.超声能有效监测肿瘤生长.

Objective To compare the features of making rabbit model bearing VX 2 liver tumor in different methods,the efficacy of agarose in preventing VX 2 carcinoma cell leakage and ultrasonographic monitoring of tumor growth. Methods Forty-five New Zealand white rabbits were randomly divided into three groups,15 rabbits in each group.Group 1,the puncture site was gently pressed using an absorbent cotton for three minutes after injecting VX 2 tumor fragment suspension 0.3 ml (107-108 cells/ml) into left lobe of the liver under the ultrasund-guidance; Group 2,VX 2 tumor fragment suspension was injected in the same way as in Group 1,except that 0.2 ml of liquefied agarose was injected to seal the puncture site; Group 3,3 pieces of 1 mm3 fragment of VX 2 carcinoma were inoculated into the sub-capsule of the left hepatic central lobe via laparotomy.Tumor growth was monitored by ultrasound and biological features of tumors were examined by routine histology.Results ①Tumors were successfully implanted in 3/15 ( 20.0%),12/15 ( 80.0%),and 11/15 ( 73.3%) of animals in group 1,group 2,and group 3,respectively,with the respective ectopic implantation rates of 12/15 ( 80.0%),3/15 ( 20.0%),and 2/13 ( 15.4%).The differences between group 1 versus group 2 and group 1 versus group 3 were statistically different. ② Under the ultrasound,most tumors were isoechoic,some tumors were hypoechoic or slightly hyperechoic,with surrounding echo halo.In all the tumors,blood flow was detected by color Doppler or power Doppler.③ Tumors were poorly demarcated from the surrounding liver parenchyma.Multiple mitotic figures were detected on histology.④ The maximum tumor diameters measured by ultrasound and microscopic pathology were closely correlated (r= 0.946,P= 0.000).Conclusions VX 2 liver tumor models were built successfully with the method of percutaneous ultrasound guided injecting tumor fragment suspension into liver parenchyma. Blockade of the tumor inoculation site with agarose plug is a useful method of preventing tumor cell leakage and ectopic implantation.Ultrasonography is useful in evaluating liver tumor growth.