CT能谱成像评价胰腺癌抗血管生成治疗效果的价值

目的:探讨CT能谱成像评价胰腺癌抗血管生成治疗效果的可行性。方法:取20只荷瘤鼠制作人胰腺癌裸鼠皮下移植瘤模型,实验组(10只鼠)分别在肿瘤种植后第15天和22天向腹腔内给予阿瓦斯汀(10mg/kg)治疗,对照组(10只鼠)给予生理盐水。在肿瘤种植后第28天行平扫和三期增强(延迟时间分别为10s、20s和1min)CT能谱扫描。基于碘-水对,测定肿瘤边缘和中心以及肝脏的碘含量,CT检查后取瘤体标本分析肿瘤组织微血管密度(MVD)-肿瘤增殖指数和Bcl-2凋亡蛋白表达水平。结果:腹腔注药后实验组肿瘤生长速度较对照组明显减慢;CT能谱检查三期增强扫描时实验组和对照组肿瘤边缘的的碘含量均高于肿瘤中心,实验组肿瘤边缘和肿瘤中心各期扫描增强时的碘含量均低于对照组,差异均有统计学意义(P<0.05)。实验组MVD、肿瘤增殖指数和Bcl-2凋亡蛋白表达水平低于对照组,差异有统计学意义(P<0.05)。CT增强各期肿瘤边缘碘含量的标准化值与MVD均存在相关性(r分别为0.955、0.837和0.961,P均<0.05)。结论:CT能谱成像能够在活体内进行肿瘤碘含量的测定,能敏感地检测肿瘤内碘含量的变化,反映肿瘤的微循环灌注情况,可以作为评价活体内肿瘤抗血管生成治疗疗效的参考指标。

CT spectral imaging in the evaluation of antiangiogenic treatment response in pancreatic cancer

Objective：To investigate the feasibility of CT spectral imaging in the evaluation of antiangiogenic treatment response in pancreatic cancer.Methods：Human pancreatic cancer xenograft model in nude mice was produced.2 weeks later,20 tumor-bearing mice were divided into experimental group and control group（10 mice in each group）.The experimental group was given Avastin（10mg/kg） by intraperitoneal administration on the Day 15 and Day 22 after tumor inoculation,while the control group was given saline.On the Day 28,nonenhanced and multi-phase（10s,20s and 1min） contrast-enhanced CT scans with GSI mode on a Discovery CT750 HD scanner were performed to all mice.The values of iodine concentrations in the tumor margin,tumor center and liver were measured.Tumor specimens were obtained to analyze the tumor microvessel density（MVD） after CT examination.Results：The tumor growth in the experimental group was significantly slower than in the control group;in the first phase（10s）,the second phase（20s） and the third phase（1min） of contrast-enhanced CT scans,iodine concentrations in the tumor margin were higher than those in the tumor center both in the experimental group and in the control group;iodine concentrations of the tumor margin and tumor center in the experimental group were less than those in the control group in every phase of contrast-enhanced CT scan and standardized differences were found（P0.05）.The MVD,proliferation index and Bcl-2 expression of tumors in the experimental group were also lower than those in the control group（P0.05）.Positive correlations were found between standardization of iodine concentrations of the tumor margin in each phase of contrast-enhanced CT scan and MVD（r were 0.955,0.837,0.961 respectively,P0.05 in every pair group）.Conclusion：Since CT spectral imaging can analyze the iodine concentrations in tumors in vivo and has the sensitivity to detect the changes of iodine concentrations,it is promising to be a method for the evaluation of the efficacy of antiangiogenic therapy for tumors in vivo.