Clin Positron Imaging 2000 Jul;3(4):183
29. F-18 FDG PET for Suspected or Confirmed Regional Recurrence of Colon
Cancer. A Prospective Study of Impact and Outcome.
Kalff V V, Hicks R, Ware R, Binns D, McKenzie A.
Purpose: Survival of patients (pts) undergoing "curative" treatment
for colorectal carcinoma remains poor. Retrospective studies suggest that F-18
FDG PET is more accurate than CT for restaging suspected recurrent disease and
favourably impacts management. The aim of this study was to confirm this by
prospective analysis.Patient Population and Methods: 102 consecutive patients
for whom the referring clinicians had prospectively committed to a treatment
plan based on conventional staging investigations and who then underwent F-18
FDG PET scanning were evaluated for management change and outcome. The accuracy
of PET results was assessed by surgical findings or clinical follow-up.Results:
Overall PET changed management in 66/102 (65%) pts including14 pts changed from
observation to active treatment after PET localized disease and 6 pts planned
for local therapy to observation after negative PET. Planned surgery was
cancelled in 28 pts whereas surgery was initiated in 11 pts. Radiotherapy was
prevented in 5 pts, initiated in 11 and the radiation field altered in 5 others.
The accuracy of the PET results could be assessed in 63/66 (95%) pts in whom
management was changed. Relapse was confirmed in 50/51 pts with a positive PET
but disease extent was underestimated in 4 cases. False negative PET results
were confirmed in 5 cases.Conclusion: FDG PET has a high and appropriate impact
on patient management in patients with suspected recurrent disease. PET can miss
small volume disease but the major benefit of PET is to prevent futile attempts
at local salvage therapies.
