Value of 11C-MET PET/CT in determinating conformal radiotherapeutic planning for high-grade gliomas

Abstract

Objective To explore the impact and value of 11C-MET PET/CT for high-grade glioma in making conformal radiotherapeutic planning compared with MRI. Methods From October 2011 to September 2013, 11C-MET PET/CT and MRI were performed in 25 initial glioma cases and 9 recurrent cases. All 34 cases (19 males, 15 females) were classified into initial group (n=17), initial surgery group (n=8) and recurrent group (n=9). GTV was outlined using PET/CT images combined with T1 weighted MRI images. Results 11C-MET PET/CT optimized radiotherapy targets in 22 cases, including 7 initial cases, 8 initial surgery cases and 7 recurrent cases. GTV was consistent with the volume of abnormally enhanced region on T1 weighted MRI (VMRI) in 10 initial cases, GTV>VMRI in 5 cases, and GTV VMRI in 2 cases and GTV<VMRI in 4 cases; 1 recurrent case's GTV located largely outside the VMRI. Conclusions There are some differences on locating the lesions of high-grade gliomas between 11C-MET PET/CT and MRI. Using 11C-MET PET/CT in sketching radiotherapy target could significantly optimize the high grade glioma's radiotherapeutic planning, which may be more valuable in recurrent or operative cases. Key words: Glioma; Radiotherapy, conformal; Tomography, emission-computed; Tomography, X-ray computed; Carbon radioisotopes; Methionine