RT Journal Article SR Electronic T1 Comparison of 18F-FLT PET and 18F-FDG PET in Esophageal Cancer JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 400 OP 404 VO 46 IS 3 A1 van Westreenen, Henderik L. A1 Cobben, David C.P. A1 Jager, Pieter L. A1 van Dullemen, Hendrik M. A1 Wesseling, Jelle A1 Elsinga, Philip H. A1 Plukker, John Th. YR 2005 UL http://jnm.snmjournals.org/content/46/3/400.abstract AB 18F-FDG PET has gained acceptance for staging of esophageal cancer. However, FDG is not tumor specific and false-positive results may occur by accumulation of FDG in benign tissue. The tracer 18F-fluoro-3′-deoxy-3′-l-fluorothymidine (18F-FLT) might not have these drawbacks. The aim of this study was to investigate the feasibility of 18F-FLT PET for the detection and staging of esophageal cancer and to compare 18F-FLT PET with 18F-FDG PET. Furthermore, the correlation between 18F-FLT and 18F-FDG uptake and proliferation of the tumor was investigated. Methods: Ten patients with biopsy-proven cancer of the esophagus or gastroesophageal junction were staged with CT, endoscopic ultrasonography, and ultrasound of the neck. In addition, all patients underwent a whole-body 18F-FLT PET and 18F-FDG PET. Standardized uptake values were compared with proliferation expressed by Ki-67 positivity. Results: 18F-FDG PET was able to detect all esophageal cancers, whereas 18F-FLT PET visualized the tumor in 8 of 10 patients. Both 18F-FDG PET and 18F-FLT PET detected lymph node metastases in 2 of 8 patients. 18F-FDG PET detected 1 cervical lymph node that was missed on 18F-FLT PET, whereas 18F-FDG PET showed uptake in benign lesions in 2 patients. The uptake of 18F-FDG (median standardized uptake value [SUVmean], 6.0) was significantly higher than 18F-FLT (median SUVmean, 3.4). Neither 18F-FDG maximum SUV (SUVmax) nor 18F-FLT SUVmax correlated with Ki-67 expression in the linear regression analysis. Conclusion: In this study, uptake of 18F-FDG in esophageal cancer is significantly higher compared with 18F-FLT uptake. 18F-FLT scans show more false-negative findings and fewer false-positive findings than do 18F-FDG scans. Uptake of 18F-FDG or 18F-FLT did not correlate with proliferation.