[18F]fluorodeoxyglucose positron emission tomography as a useful indicator of metastatic gestational trophoblastic tumor: preliminary results in three patients.
OBJECTIVE
The goal of this study was to evaluate the usefulness of positron emission tomography with [(18)F]fluorodeoxyglucose ([(18)F]FDG-PET) in detecting metastases in patients with gestational trophoblastic tumor (GTTs).


METHODS
A retrospective study was conducted on three patients with GTTs who had been studied with [(18)F]FDG-PET and computed tomography (CT) after an increase in human chorionic beta-gonadotropin (betahCG) serum levels. PET scans were performed with a multiring whole-body positron emission tomograph 45 min after an intravenous bolus injection of [(18)F]FDG ( approximately 5.2 MBq/kg). CT studies were obtained on a spiral scanner prior and after administration of intravenous iodinated contrast material. Within a week of CT and [(18)F]FDG-PET studies, the patients underwent surgical procedures for histological diagnosis.


RESULTS
In one patient, a lung lesion positive for neoplastic tissue with [(18)F]FDG-PET and negative with CT was confirmed to be a GTT metastasis at histology. In another patient, [(18)F]FDG-PET was negative, while CT was positive for the presence of lung metastasis; no viable tumor tissue was found at histological analysis. The remaining patient had a positive [(18)F]FDG-PET and CT study for lung metastasis; this was confirmed at histological analysis. In the same patient, both [(18)F]FDG-PET and CT depicted the presence of a liver lesion. Necrotic lesion regression after treatment was clearly documented with [(18)F]FDG-PET only.


CONCLUSIONS
Our preliminary results suggest that [(18)F]FDG-PET may be useful for the assessment of metastatic disease in patients with GTTs.
Sironi
S
S
University of Milano-Bicocca, Milan, Italy. fazio.ferruccio@hsr.it
Picchio
M
M
Mangili
G
G
Garavaglia
E
E
Zangheri
B
B
Messa
C
C
Voci
C
C
Taccagni
G L
GL
del Maschio
A
A
Fazio
F
F
D000328:Adult; D005260:Female; D019788:Fluorodeoxyglucose F18; D031901:Gestational Trophoblastic Disease / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D008875:Middle Aged; D011247:Pregnancy; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014055:Tomography, Emission-Computed / Q000379:methods
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18