Suspicious for recurrent low and high grade glioma and indeterminate MRI: the role of 18F-DOPA PET/CT

Abstract

1691 Objectives: ACKGROUND. The aim of present study was to assess the role of 18F-FDOPA PET/CT in patients who had a suspicious forrecurrent low and high grade glioma but with an indeterminate MRI.MATERIALS AND METHODS . From a monocentric database, we retrospectively analyzed 21 patients (median age: 60 yrs;19-80) who underwent 18F- DOPA PET/CT for the restaging of low and high grade glioma. All PET/CT images werere-examined by two nuclear medicine physicians. Both visual and semiquantitative analysis was used for the interpretation ofimages. At visual analysis, PET/CT was defined as positive in case of a DOPA uptake in the lesion (identified by MRI) higherthan controlateral striatum uptake. For the semiquantitative analysis, the ratios between SUVmax of the lesion and SUVmax ofthe striatum (T/S)/normal brain tissue (T/B) equal to 1 and 2 respectively were used. Clinical reassessment consisted of standardevaluation including MRI and assessment of neurological symptoms. The agreement between visual and semiquantitativeanalysis was obtained by k statistical analysis. Diagnostic performance was calculated by standard methods.RESULTS. Six patients had a low grade glioma and 14 a high grade. At visual analysis, 15 (75%) patients had a positive PET/CTresult, in particular 4 with a low grade glioma and 11 with a high grade (67% and 79%, respectively). Based onsemiquantitative analysis, 14 (70%) and 14 (70%) patients had a positive PET/CT, respectively for T/S and T/B. The agreementbetween visual and semiquantitative analysis was 88% (p