1. Shengjing Hospital of China Medical University, Shenyang 110004, China; 2. General Electronic Company(China)Healthcare, Beijing 100176, China; 3. Shantou Center Hospital, Shantou Guangdong 515031, China;4. Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100021, China
Abstract：Objective: To evaluate the clinical value of dual phase 18F-FDG imaging in the diagnosis of indeterminate pulmonary nodules. Standard uptake value(SUV), rate of change of lesion volume and lesion glycolysis(LG) were analyzed and evaluated. Materials and Methods: Thirty-one cases were included in this study, all had dual phase 18F-FDG PET/CT. Scanning began after 60 min injection of 18F-FDG, was the conventional imaging, and 120 min after injection was the delayed scanning. In the patients, 25 were male and 6 were female, the average age was 57.09±13.38 years old. Twelve cases had benign pulmonary lesions(4 were granulomatous inflammatory lesion, 8 were tuberculosis), adenocarcinoma and squamous cell carcinoma in 15 cases, metastatic tumors in 4 cases. The data of SharpIR+VUE HD+TOF in all patients were selected to reconstruct PET images. GE PET VCAR tool was used to obtain maximaum SUV(SUVmax), average SUV(SUVav), volume of lesion, LG value and rate of change. Results: On dual phase 18F-FDG PET delayed imaging, the SUVmax and SUVav of granulomatous inflammatory lesion, tuberculosis, inflammation+tuberculous lesion, primary pulmonary carcinoma and metastatic tumor all had various degrees of increase. The degree of increase in SUVmax was more marked than SUVav. In inflammatory lesion the increase of SUVmax and SUVav was most obvious, that was 17.97%, and the increase in primary carcinoma was the least being 2.6%. There was either increase or decrease in volume of lesion and LG value. In tuberculosis the decrease in lesion volume was most marked that was -35.4%. The decrease of LG value in primary lung cancer was most marked, being -19.00%. Conclusion: The changes of SUVmax and SUVav in dual phase 18F-FDG PET/CT is not useful in differentiating benign and malignant pulmonary nodules. Lesion volume and LG change rate has potential capability in increasing the accurate diagnosis of indeterminate pulmonary nodules, and can be useful in the early diagnosis of primary pulmonary carcinoma.
2012, Vol. 23 
