11C-胆碱与18F-FDG双时相PET显像在孤立性肺结节鉴别诊断中的应用

目的 比较^11C-胆碱、18F-脱氧葡萄糖（FDG）和^18F-FDG双时相PET显像对鉴别肺部孤立性结节良恶性的价值。方法16例临床疑为肺肿瘤的患者进行^18F-FDGPET显像（注药后1h显像，2h后行延迟显像）、^11C-胆碱PET显像（3d内，于注药后10min进行）。图像判断以标准摄取值（SUV）作为半定量指标，异常放射性浓聚灶以SUV〉2．5为葡萄糖代谢增高，^18F-FDG延迟显像SUV上升≥10％为恶性病变（阳性），如下降或升高〈10％为良性病变（阴性）；^11C-胆碱异常摄取灶以SUV〉2．0为阳性。所有病例进行随访，以显像诊断是否符合病理检查结果作为判断标准。结果病理检查结果证实12例肺癌，3例结核，1例结节病。^11C-胆碱PET显像确诊了12例肿瘤中的ll例，而^18F-FDG PET显像确诊10例（10／12例），双时相^18F-FDG PET显像确诊11例。4例良性病变者，^11C-胆碱PET显像能较好鉴别；而^18F-FDG PET显像2例假阳性，结合延迟显像仅1例假阳性。结论 ^11C-胆碱和^18F-FDG PET显像均能较好地鉴别肺部良恶性肿瘤。但^11C-胆碱和双时相^18F-FDGPET显像优于常规^18F-FDGPET显像，三者联合能提高对肺部病变的诊断效率。

The use of 11C-choline, 18F-FDG and delayed 18F-FDG PET imaging for the differential diagnosis of SPN

Objective To compare the value of ~(11)C-choline PET imaging with ~(18)F-fluorodeoxyglu- cose(FDG)and delayed ~(18)F-FDG PET imaging for the differential diagnosis of solitary pulmonary nodule (SPN).Methods 16 patients with suspected lung tumors were examined by PET imaging.Both ~(11)C-cho- line and ~(18)F-FDG PET imaging were performed within 3 d in each case.~(11)C-choline PET imaging was per- formed 10 min after injection,while ~(18)F-FDG PET imaging and 2 h delayed imaging were performed 1 and 2 h after injection,respectively.Standardized uptake value(SUV)was calculated for quantitative assessment of tumor uptake.Took baseline ~(18)F-FDG SUV>2.5 and increased 10% or more than 10% in delayed ~(18)F- FDG imaging as positive finding,while SUV decreased or increased less than 10% as negative one.In ~(11)C- choline imaging SUV>2.0 was considered as malignancy.All results followed with surgical pathology.Re- sults Twelve-lung cancer,3 pulmonary tuberculosis,1 sarcoidosis were verified by pathology.Within the 16 untreated patients,~(11)C-choline PET imaging correctly detected cancer in 11 patients,whereas ~(18)F-FDG PET imaging detected in 10 but in 11 with delayed imaging.In 4 benign cases,all were positive in ~(11)C-cho- line,while 2 false positive in ~(18)F-FDG but only 1 in delayed ~(18)F-FDG PET imaging.Conclusions Lung tumors can be well differentiated with ~(11)C-choline and ~(18)F-FDG PET imaging,~(11)C-choline PET combined with delayed ~(18)F-FDG PET imaging is superior to ~(18)F-FDG PET imaging alone.Thereby,three methods combined each other can increase the diagnostic value of lung lesion.