Direct comparison of 18F-fluorodeoxyglucose coincidence gamma camera tomography with gallium scanning for the staging of lymphoma.

BACKGROUND

The present study compared the performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) using a coincidence dual-head gamma camera (FDG Co-PET) with 67gallium scinti graphy (GS) in pretreatment staging of lymphoma.

METHODS

A total of 46 patients underwent FDG Co-PET, computed tomography (CT) scanning and GS for pretreatment staging of lymphoma (40 newly diagnosed and recurrence) between November 1997 and December 1999.

RESULTS

Histological subgroups comprised low grade (8 patients), intermediate grade (25) high-grade (3) non-Hodgkin's lymphoma and Hodgkin's disease (10). Based on clinical assessment, CT scan findings and biopsy, 100 nodal sites and 15 extra-nodal sites were deemed positive. FDG Co-PET was superior to GS in nodal site positivity rate (97%vs 79%, P < 0.0001). Compared with GS, FDG Co-PET detected 39 more abnormal sites in 22 patients (48%), of which 28 sites were validated by biopsy, CT and/or progress FDG Co-PET scanning. There was only one proven false negative FDG site in the spleen. CT + FDG Co-PET led to upstaging in 2 patients (4%), compared to CT + GS.

CONCLUSION

FDG Co-PET shows potential for providing an accurate means for pretreatment staging of lymphoma and can detect extra sites of disease activity compared to GS.