Differential diagnosis of rat C6 glioma and inflammation with 18F-FDG, 11C-MET and 11C-CHO PET/CT imaging and their correlations with HIF-1α and VEGF / 中华核医学与分子影像杂志

ABSTRACT

Objective To compare 18F-FDG、11C-MET and 11C-CHO PET/CT in rat C6 glioma and inflammation models and observe their correlations with HIF-1α and VEGF expressions.Methods Thirtytwo male Wistar rats were included to bear both C6 glioma and turpentine oil-induced acute inflammation (AI).18F-FDG,11C-MET and 11C-CHO PET/CT were performed on rats.The SUVmax ratios of tumor-tomuscle (T/M),AI-to-muscle (AI/M) and tumor selectivity index (SI) were calculated.One-way analysis of variance and two-sample t test were used for statistical analyses.HIF-1α and VEGF expression was detected by immunohistochemical staining.Spearman correlation analysis was performed to evaluate the relationship between T/M ratios and the expressions of HIF-1α or VEGF.Results T/M ratios of 18F-FDG,11 C-MET and 11C-CHO in C6 glioma were 6.89±2.53,2.75±0.87,2.73±1.01,and the AI/M were 4.77±2.21,1.75±0.66,2.23±0.90 respectively.The 18F-FDG and 11C-MET uptake between C6 glioma and AI were significantly different(tFDG =2.133,tMET =3.267,both P＜0.05).The SIMET was significantly higher than SIFDG(t =2.600,P＜0.05).The 11C-CHO uptake between tumor and inflammation showed no significant difference(t=1.537,P＞0.05).T/M ratios of 18F-FDG and 11C-MET were positively related to HIF-1α and VEGF expressions(rs =0.725,0.637,0.621,0.764,all P＜0.05).The T/M ratio of 11C-CHO related only to VEGF (rs =0.682,P＜0.05).Conclusions 18F-FDG and 11 C-MET PET/CT may differentiate C6 glioma from AI,and 11 C-MET PET/CT seems more tumor-selective.11C-CHO PET is less valuable for the differential diagnosis.The 18F-FDG and 11 C-MET uptake of C6 glioma may be related to tumor hypoxia.All the three tracers could reflect tumor angiogenesis,but with different sensitiveness.