Head-to-head comparison of [18F]-fluorodeoxyglucose and [18F]-fluorocholine positron emission tomography/computed tomography in three patients with rare gestational trophoblastic neoplasms: A case series

We report the efficacy of dual positron emission tomography/computed tomography (PET/CT) imaging with [(18)F]-2'-fluoro-2'-deoxy-D-glucose ([(18)F]-FDG) and [(18)F]-fluorocholine ([(18)F]-FCH) in patients with gestational trophoblastic neoplasia (GTN) for primary diagnosis and staging of this rare pregnancy-related disorder. Whole-body PET/CT with [(18)F]-FDG and [(18)F]-FCH was performed in three patients with GTN in 2 consecutive days. Each detectable lesion was characterized by visual and quantitative analyses. As compared to CT alone, PET/CT with [(18)F]-FDG and [(18)F]-FCH PET/CT revealed more hypermetabolic metastatic lesions in the body, but not in the brain. The standard uptake value of [(18)F]-FDG was generally higher than [(18)F]-FCH in all detectable tumor lesions. In conclusion, both [(18)F]-FDG and [(18)F]-FCH PET/CT can be used for diagnosis and staging for GTN, based on their sensitivity for small extracerebral metastatic lesions. Additional studies are warranted to determine whether the PET/CT imaging with [(18)F]-FDG and [(18)F]-FCH can serve as a biomarker of GTN aggressiveness, for prediction of treatment response.