J Nucl Med 2001 Nov;42(11):1605-13
The utility of (18)F-FDG PET for suspected recurrent non-small cell lung
cancer after potentially curative therapy: impact on management and prognostic
stratification.
Hicks RJ, Kalff V, MacManus MP, Ware RE, McKenzie AF, Matthews JP, Ball DL.
After potentially curative therapy of non-small cell lung cancer (NSCLC), masses
or symptoms suggestive of relapse are common but may be difficult to
characterize. Early detection is important because salvage therapies are
available for localized recurrence. This study evaluated whether (18)F-FDG PET
is useful and predictive of outcome in this setting. METHODS: For 63 consecutive
patients with suspected relapse >6 mo after definitive treatment of NSCLC,
the apparent extent of disease on conventional restaging was compared with that
on FDG PET. Patients with already confirmed systemic metastases were excluded
unless locally aggressive treatment of these was being considered. Serial
imaging and pathologic results were obtained during a median follow-up of 19 mo
to validate diagnostic findings. Prognostic significance was tested using the
Cox proportional hazards regression model. RESULTS: PET had positive findings in
41 of 42 patients with confirmed relapse (sensitivity, 98%). No disease was
evident during a minimum follow-up of 12 mo in 14 of 15 patients with clinically
suspected relapse but negative PET findings (negative predictive value, 93%).
PET induced a major management change in 40 patients (63%), including 6 whose
treatment was changed from curative to palliative, 3 whose treatment was changed
from palliative to curative, and 9 for whom negative PET findings prevented
active management. Both the presence (P = 0.012) and the extent (P < 0.0001)
of relapse on PET were highly significant prognostic factors. There was also
significant prognostic stratification based on the treatment delivered after the
PET study (P = 0.011), but after adjustment for this treatment, PET status
remained highly predictive of survival. CONCLUSION: PET better assesses the
status of disease and stratifies prognosis than does conventional staging,
affects patient management, and should be incorporated into paradigms for
suspected recurrence of NSCLC.
