Experimental study on multiple tracers PET/CT in the differentiation of C6 glioma from different inflammation / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the value of 18F-FDG,11C-MET and 11C-CHO PET/CT in the differentiation of C6 glioma from different kinds of inflammation in experimental rat models.Methods (1) A total of 48 male SD rats were randomly divided into 6 groups by the random number tablegroup 1 and 2 consisted of 8 rats bearing both C6 glioma and turpentine oil-induced acute inflammation;group 3 and 4 consisted of 8 rats bearing both C6 glioma and turpentine oil-induced chronic inflammation;group 5 and 6 consisted of 8 rats bearing both C6 glioma and BCG-induced granuloma.(2) 18F-FDG and 11C-MET PET/CT were performed on rats of group 1,3 and 5;18F-FDG and 11C-CHO PET/CT were performed on rats of group 2,4 and 6.The lesion-to-muscle ratios and tumor selectivity index (SI) were calculated.(3)After the PET/CT imaging,the lesions were excised.Immunohistochemical staining was used to demonstrate the situation of Glut-1,HIF-1α and CD98.(4)Two-sample t test,Nemenyi test and nonparametric Kruskal-Wallis H test were used for statistical analyses.Results (1) 18 F-FDG and 11 C-MET uptake in C6 glioma were higher than those in different inflammatory tissues(t--1.425-3.901,all P＜0.05).The 11 C-CHO uptake among different lesions were not significant (t =0.031-3.901,all P＞0.05).In group 1 and 5 models,SIMET(4.22±2.96 and 4.89±2.08) was significantly higher than SIFDG(1.77±0.86 and 1.72±0.77;t =2.717and 2.490,both P＜0.05);but iu group 3 models,SIMET(3.84±2.71) was not significantly higher than SIFDG(2.28± 1.14;t =2.082,P＞0.05).(2) Immunohistochemical study showed that there were significant differences in the expression of HIF-1 α,CD98 among different lesions (H =17.810,26.540,both P ＜ 0.05),and no significances of expression of Glut-1 among different lesions (H=5.940,P＞0.05).Nemenyi test showed that there was significant difference for CD98 expression between C6 glioma and acute inflammation,C6 glioma and granuloma (x2=5.504,9.345,both P＜O.05),and for HIF-1α and CD98 expression between C6 glioma and chronic inflammation (x2 =-5.938,2.128,both P＜0.05).Conclusions Compared with 18F-FDG and 11 C-CHO,11 C-MET has better tumor specificity.11 C-CHO PET/CT is not suitable for the differentiation of tumor and inflammation because of its lowest specificity.