11C-鬼臼毒素和^18F-脱氧葡萄糖示踪剂在小鼠肺癌模型PET影像学检查中的应用

Compararison of the biodistribution and PET imaging with 11C-PDT and 18F-FDG in the mouse model of lung adenocarcinoma

目的对比11C-鬼臼毒素（PDT）和^18F-脱氧葡萄糖（FDG）在荷肺腺癌小鼠体内的生物学分布及在PET中的显像，评价^11C-PDT作为新型示踪剂在肺癌显像中的作用。方法24只荷肺腺癌小鼠随机分为2组，每组12只，分别经尾静脉注入11C—PDT和^18F-FDG，于注药60min后用井型探测仪测量^11C-PDT和^18F-FDG在小鼠各脏器内的生物学分布，并行PET显像。结果^11C-PDT和^18F-FDG在肿瘤组织中均有较高的放射性摄取，但是^11C—PDT组肿瘤组织的放射性摄取值[（0．65±0．20）％ID／g]明显低于^18F-FDG组[（7．44±1．56）％ID／g，P〈0．01]。^11C-PDT组放射性摄取最高的部位依次为肝、肾和血液，而^18F—FDG组放射性摄取最高的部位依次为心脏、肿瘤和肾。^11C—PDT组中，肿瘤组织对肌肉组织的T／NT值相对较高，达2．02±0．56，但仍低于^18F—FDG组（2．95±0．49，P〈0．01）。^11C—PDT组中，肿瘤组织对其他脏器的T／NT值均〈2。^11C—PDT组荷肺腺癌小鼠PET显像可见腹腔脏器及肿瘤部位有放射性热区，^18F—FDG组可见心脏、肿瘤及腹腔脏器放射性浓聚明显，两种示踪剂的肿瘤显像均较清晰。结论^11C—PDT在肺癌组织中的摄取高于肌肉组织，通过PET显像可以显示肺部肿瘤。11C—PDT可以作为肺癌显像的示踪剂。

Objective The objective of this study was to compare the biodistribution and PET imaging of 11C-PDT and 18F-FDG in a mouse model of lung adenocarcinoma, and to evaluate the value of 11C-PDT as a new tracer for PET imaging of lung cancer. Methods Twenty four lung adenocarcinomaheating mice were randomly divided into two groups, 12 each. The mice received 11C-PDT or ISF-FDG injection i.v. respectively. The biodistribution of 11C-PDT or ISF-FDG in the mice was measured with a wellgamma detector at 60min after injection. The PET imagings of mice were performed using either of the two tracers. Results Considerable uptake of the both radioactive tracers in the tumors was observed. The tumor uptake of NC-PDT [ （0.65 ± 0.20）% ID/g] was significantly lower than that of 18F-FDG [（7.44 ± 1.56） % ID/g, P 〈0.01 ]. In the 11C-PDT group, the highest uptake was observed in the liver, kidney and blood in a successively declining order, while the highest uptake of 18F-FDG was seen in a order of heart, tumor and kidneys. The tumor/muscle ratio of 11C-PDT. uptake was relatively high （2.02 ± 0.56）, but still lower than that of 18F-FDG （ 2.95 ± 0.49, P 〈 0. 01 ）. All values of other tumor/organ ratios （T/NT） of 11 C-PDT uptake were 〈 2. High radioactive uptake was showed in the tumor and abdominal organs on PET images in the tumor-beating mice injected with 11C-PDT, and 18F-FDG uptake was showed in the heart, tumor and abdominal organs. The tumor PET images with 11C-PDT and 18F-FDG were all clear. Conclusion The uptake of 11C-PDT in lung cancer is higher than that in muscle tissues, and pulmonary cancers can be detected by PET imaging, 11C-PDT may be a promising PET tracer for lung cancers.