439P - Comparison of Ct and 18F-Flt Pet/Ct Imaging for Target Volume Delineating in Patients with Glioma

Abstract

ABSTRACT Aim: The aim of this pilot study was to compare computed tomography (CT) and 3′-deoxy-3′-[18F] fluorothymidine (18F-FLT) positron emission tomography/ computed tomography (PET/CT) imaging for gross tumor volume (GTV) and clinical target volume (CTV) delineation, and to analyze the impact of proliferative tumor volume delineated by 18F-FLT PET/CT. Methods: 12 patients with glioma were enrolled into this study. The relation of 18F-FLT uptake and pathology, Ki-67 index were studied in 9 patients. All of the 12 patients underwent 18F-FLT PET/CT imaging before radiotherapy. The enhanced CT images and 18F-FLT PET/CT images were all transferred to planning system and the target volumes from each image were delineated and compared. Results: 18F-FLT PET/CT SUVmax increased significantly with glioma grade (p = 0.007). SUVmax of 18F-FLT PET/CT (p= 0.03), T/N ratio (p Conclusions: The uptakes of 18F-FLT were positively correlated with grade of glioma and tumor cell proliferation index. To delineate target volume by 18F-FLT PET/CT imaging, the GTV and CTV are smaller than CT. It maybe improves the accuracy of GTV and CTV in patients with glioma and, meanwhile, provides potential benefits to normal brain tissue. Disclosure: All authors have declared no conflicts of interest.