文摘
Objective PET imaging with 18F-FDOPA has been successfully applied in the diagnosis and surveillance of neuroblastoma (NB) by targeting the overexpression of aromatic l-amino acid decarboxylase. This study aims to assess the impact of residual 18F-fluoride on 18F-FDOPA PET in NB and to implement a method to maintain low 18F-fluoride content in future studies. Methods Automatic synthesis of 18F-FDOPA was based on the electrophilic method using TRACERlab FXFE module. Radio-TLC was employed to determine residual 18F-fluoride levels. We analyzed the impact of residual 18F-fluoride on the images of 35 patients undergoing 18F-FDOPA PET at initial diagnosis and/or follow-ups of NB. Results In 35 batches of 18F-FDOPA products from 9/28/2010 to 07/27/2011, the mean residual 18F-fluoride level was 4.4?% (range 0.2-9.1?%). Residual 18F-fluoride level ?.0?% was associated with dense uptake in the growth plates, skull, and pelvis on PET scans, which may interfere with the interpretation of 18F-FDOPA imaging in NB. By applying stringent restraints in 18F-FDOPA?production, including regular renewal of reagents, exclusive use? of NH4OH, and timely replacement of HPLC column, the incidence of 18F-FDOPA batches with residual 18F-fluoride level ?.0?% was reduced from 33 to 4?% (P?<?0.0001) during 7/30/2011-/29/2013. Conclusion By monitoring residual 18F-fluoride levels and keeping stringent restraint procedures, low 18F-fluoride content was achieved in most batches of 18F-FDOPA, which diminished false-positive skeletal uptake. An appropriate upper limit of 18F-fluoride level is suggested to be included in the criteria of routine quality control of 18F-FDOPA productions.