Abstract
IntroductionThe demand for early-response evaluation with 2-deoxy-2-[18F] fluoro-D-glucose (F-18-FDG) positron emission tomography combined with whole body CT (PET/CT) is rapidly growing. This study was initiated to evaluate the applicability of the PET response criteria in solid tumours (PERCIST 1.0) for response evaluation.
MethodsWe performed a retrospective study of 21 patients with locally advanced non-small cell lung cancer (NSCLC), who had undergone both a baseline and a follow-up F-18-FDG-PET/CT scan during their treatments. The scans were performed at our institution in the period September 2009 and March 2011 and were analysed visually and according to PERCIST 1.0 by one board-certified nuclear medicine physician. The response was compared with overall survival (OS) and progression-free survival (PFS). The variation in key parameters affecting the F-18-FDG uptake was assessed.
ResultsA kappa of 0.94 corresponding to an almost perfect agreement was found for the comparison of the visual evaluation with PERCIST. Patients with partial metabolic response and stable metabolic disease (as evaluated by PERCIST 1.0) had statistically significant longer median time to progression: 8.4 months (confidence interval (CI) 5.1-11.8 months) as compared with 2.7 months (CI 0-5.6 months) in patients classified with progression. The variation in uptake time between baseline and follow-up scans was more than the recommended 15min in 48% of patients.
ConclusionsPERCIST 1.0 is readily implementable and highly comparable with visual evaluation of response using early F-18-FDG-PET/CT scanning for locally advanced NSCLC patients. In spite of variations in parameters affecting F-18-FDG uptake, evaluation of F-18-FDG-PET/CT during treatment with PERCIST 1.0 is shown to separate non-responders from responders, each with statistically significant differences in both OS and PFS.