Comparison on the diagnostic values of 18F-FDG and 18F-FLT PET/CT in patients with suspicious recurrence of glioma after multimodal treatment / 中华核医学与分子影像杂志

ABSTRACT

Objective To compare the diagnostic values of 18F-FDG and 18F-FLT PET/CT in patients with suspicious recurrence of glioma after multimodal treatment.Methods A total of 20 patients (13 males,7 females;age range12-73 years) with glioma who underwent 18F-FDG and 18F-FLT PET/CT due to abnormal enhancement on MRI from January 2012 to June 2015 were enrolled in this retrospective study.According to the pathological or follow-up results,patients were divided into therapy-related benign changes (TRBC) group and recurrent glioma group,the later was subdivided into initial low-grade glioma (LGG) group and initial high-grade glioma(HGG) group.T/NT ratios of 18F-FDG and 18F-FLT between HGG (LGG) group and TRBC group were compared using one-way analysis of variance and the least significant difference t test.ROC curve analysis was conducted to calculate the differential diagnostic efficiency of 18F-FDG and 18F-FLT between TRBC and recurrent glioma.Results A total of 14 patients were proved as recurrent glioma and 6 patients as TRBC.The mean 18F-FDG T/NT ratios of HGG group,LGG group and TRBC group were 2.31±0.86,1.32±0.86 and 1.32±0.64,respectively.The 18F-FDG T/NT ratio of the HGG group was significantly higher than that of the TRBC group(F=3.671,t=-2.471,P＜0.05).The mean 18F-FLT T/NT ratios of HGG group,LGG group and TRBC group were 8.94±3.14,7.18±3.29 and 1.92±1.20,respectively (F=13.301,t values-5.150 and-2.360,both P＜0.05).The optimal T/NT cutoff values for 18 F-FDG and 18F-FLT PET/CT were 1.62 and 4.58,respectively.The sensitivity,specificity and accuracy of detecting recurrent glioma with optimal T/NT cutoff value were 11/14,5/6 and 16/20 for 18F-FDG PET/CT,and those for 18F-FLT PET/CT were 13/14,6/6 and 19/20,respectively.No significant difference was observed between the diagnostic efficiencies of the two imaging modalities (x2 values1.167,1.091 and 2.057;all P＞0.05).Conclusion There were no statistical significances between 18F-FDG and 18F-FLT PET/CT on the differential diagnosis of glioma recurrence.