title: Performance of FLT-PET for pulmonary lesion diagnosis compared with traditional FDG-PET: A meta-analysis.
abstract: OBJECTIVE
  Widely used (18)F 2'-deoxy-2'-fluoro-d-glucose (FDG) positron emission tomography (PET) can be problematic with false positives in cancer imaging. This study aims to investigate the diagnostic accuracy of a candidate PET tracer, (18)F 2',3'-dideoxy-3'-fluoro-2-thiothymidine (FLT), in diagnosing pulmonary lesions compared with FDG.
  
  
  METHODS
  After comprehensive search and study selection, a meta-analysis was performed on data from 548 patients pooled from 17 studies for evaluating FLT accuracy, in which data from 351 patients pooled from ten double-tracer studies was used for direct comparison with FDG. Weighted sensitivity and specificity were used as main indicators of test performance. Individual data was extracted and patient subgroup analyses were performed.
  
  
  RESULTS
  Overall, direct comparisons showed lower sensitivity (0.80 vs. 0.89) yet higher specificity (0.82 vs. 0.66) for FLT compared with FDG (both p<0.01). Patient subgroup analysis showed FLT was less sensitive than FDG in detecting lung cancers staged as T1 or T2, and those ≤2.0 cm in diameter (0.81 vs. 0.93, and 0.53 vs. 0.78, respectively, both p<0.05), but was comparable for cancers staged as T3 or T4, and those >2.0 cm in diameter (0.95 vs. 1.00, 0.96 vs. 0.88, both p>0.05). For benignities, FLT performed better compared with FDG in ruling out inflammation-based lesions (0.57 vs. 0.32, p<0.05), and demonstrated greater specificity regardless of lesion sizes.
  
  
  CONCLUSIONS
  Although FLT cannot replace FDG in detecting small and early lung cancers, it may help to prevent patients with larger or inflammatory lesions from cancer misdiagnosis or even over-treatment.
authors: Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences/School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
authors: Zixing
authors: Z
authors: Wang
authors: Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences/School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
authors: Yuyan
authors: Y
authors: Wang
authors: Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100005, China.
authors: Xin
authors: X
authors: Sui
authors: Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100005, China.
authors: Wei
authors: W
authors: Zhang
authors: National Institutes for Food and Drug Control, Beijing, 100000, China.
authors: Ruihong
authors: R
authors: Shi
authors: Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100005, China.
authors: Yingqiang
authors: Y
authors: Zhang
authors: Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100005, China.
authors: Yonghong
authors: Y
authors: Dang
authors: Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100005, China.
authors: Zhen
authors: Z
authors: Qiao
authors: Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences/School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
authors: Biao
authors: B
authors: Zhang
authors: Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, 100005, China. Electronic address: cjr.songwei@vip.163.com.
authors: Wei
authors: W
authors: Song
authors: Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences/School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China. Electronic address: jingmeijiang238@hotmail.com.
authors: Jingmei
authors: J
authors: Jiang
mesh_terms: D015224:Dideoxynucleosides; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D008175:Lung Neoplasms / Q000175:diagnosis*; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: C479242:2',3'-dideoxy-3'-fluoro-2-thiothymidine; D015224:Dideoxynucleosides; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: FDG; FLT; Lung neoplasms; Positron-emission tomography