Differential diagnosis of pulmonary tuberculomas and malignant nodules using18F-FLT and 18F-FDG PET/CT imaging
CHEN Wen-xin1, LIN Mei-fu1, TIAN Jia-he2, YANG Xiao-feng3, YU Li-juan4, WANG Xue-mei5, XIN Jun6, FENG Hui-ru7, CHEN Ping8, ZHAO Zhou-she9, GUO Shen1, CHEN Guo-bao1
1. Department of Nuclear Medicine, Provincial Clinical Hospital of Fujian Medical University, Fuzhou 350001, China;2. The PLA General Hospital, Beijing 100853, China; 3. The People’s Hospital of Xinjiang Autonomous Region,Urumqi 830001, China; 4. The Third Affiliated Hospital of Harbin Medical University, Harbin 150001, China;5. The Affiliated Hospital of Inner Mongolia Medical College, Hohhot 010000, China; 6. Shengjing Hospital ofChina Medical University, Shenyang 110004, China; 7. General Hospital of Beijing Military Area Command,Beijing 100700, China; 8. The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China;9. GE Medical Systems(China) Co., Ltd, Beijing 100176, China
Abstract：Objective: To investigate the diagnostic efficacies of 18F-FLT and 18F-FDG PET/CT in pulmonary nodules, focusing on diagnosis and differential diagnosis of pulmonary tuberculomas and malignant nodules. Materials and Methods: 163 patients with solitary pulmonary nodules undergoing dual-tracer imaging were certified by histological findings. The patients were collected from a multicenter clinical trial and were divided into the group of pulmonary tuberculoma(n=29), group of other benign nodule(n=48) and group of malignant nodule(n=88). The images were read in a standardized, blind, collective reading. The standardized uptake value(SUV) of 18F-FDG and 18F-FLT were compared and analyzed. Results: The SUVs of FDG and FLT in groups of malignant nodule, tuberculoma and other benign nodule were in a decreasing order. Both SUVFDG and SUVFLT showed significant difference in the group of malignant nodule and tuberculoma(P<0.001). ROC curve showed that a SUV cutoff of 5.9 on FDG PET/CT and 2.4 on FLT PET/CT provided the best separation of tuberculomas and malignancies. FLT PET/CT had higher diagnostic efficacy than FDG PET/CT(P<0.001). The ratio between SUVs of 18F-FLT and 18F-FDG improved the diagnostic efficacy in comparison with single tracer imaging. Conclusions: Dual-tracer imaging using 18F-FDG/18F-FLT PET/CT provides a better diagnostic efficacy in these clinically challenging patients with pulmonary lesions. A SUV cutoff of 5.9 on FDG PET/CT and 2.4 on FLT PET/CT provide the best separation of tuberculomas and malignancies. The ratio between SUVs of 18F-FLT and 18F-FDG provides great potential benefits in separating tuberculomas and malignancies.
2012, Vol. 23 
