18F-FDG PET/CT IN THE EVALUATION OF ICSOLs

Abstract

The aim of the study was to assess the diagnostic value of F-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computerized tomography (PET/CT) in evaluating and possible grading of intracranial space-occupying lesions. METHODS:We included 27 patients from a tertiary care institute in north India. All patients were subjected to history taking, clinical examination, followed by baseline investigations and imaging. Cases were allocated to 4 distinct groups based on the World Health Organization (WHO) classification post-clinico-histological diagnosis: Low-grade tumors (25.9%), highgrade tumors (18.5%), metastases (48.1%), and other lesions (7.4%). Patients did contrast enhanced computerized tomography (CECT), contrast enhanced magnetic resonance imaging (CEMRI) and 18F-FDG PET/CT preoperatively. Postoperative follow-up was done, and the gold standard for tumor grading was the histopathology. RESULTS:High-grade tumors (WHO Grade III/IV & IV/IV) did not show statistically significant standardized uptake values (SUV) max or SUVmax per unit volume indices compared with low-grade tumors or metastatic lesions. CONCLUSION:The current study results suggests that 18F-FDG PET/CT indices of SUVmax or SUVmax per unit volume of the tumors by themselves are not reliable indices for differentiating high-grade tumors from lower grade ones or metastases; however, PET-CT imaging could rule out metastases from primary central nervous system (CNS) malignancies by evaluating the rest of the body.