| ObjectiveTo assess the role of maximum standardized uptake value(SUVmax)as a biomarker of 18F-fluorodeoxyglucose(FDG)-positron emission tomography/computed tomography(PET/CT)to differentiate active and inactive patients.Methods.78 TA patients underwent 18F-FDG PET/CT at FUWAI hospital from January 2016 to March 2018(63 women and 10 men;median age 38± 14 years).Biomarkers including C-reactive protein,erythrocyte sedimentation rate were measured.Diseases activity of all TA cases was defined by two Takayasu arteritis experts independently,and this evaluation criteria incorporate National Institutes of Health criteria,clinical manifestations,laboratory and imaging results.We respectively classified all cases by their disease activity as apparent active cases,mild active cases and stable cases.18 patients referred for whole body PET/CT scan for indications other than vasculitis served as controls.Results.The SUVmax was significantly higher in apparent active TA cases(4.25±2.00)than in other cases and controls(mild activity,means,2.59±0.44 vs.stable activity,means,2.27±0.52 vs.control,means,2.15±0.50;P<0.001).Given a SUVmax cutoff of 3.10,the sensitivity for apparent active patients was 94.12%,the specificity was 95.08%,the AUC was 0.964.In receiver-operating characteristic curves(ROC)comparison,SUVmax was superior to erythrocyte sedimentation rate and C-reaction protein(SUVmax,AUC 0.964 vs.ESR,AUC 0.810 vs.CRP,AUC 0.711;P<0.001).But mild active cases did not differ significantly in terms of SUVmax,ESR,CRP.Correlations between SUVmax and ESR or CRP were no statistically significance(p>0.05).Conclusions.PET/CT showed good sensitivity and specialty to detect active TA.We determined the cutoff for SUVmax was 3.10 with about 95%of sensitivity and specificity.SUVmax was associated with disease activity,which could be a new biomarker for the assessment of disease activity and response to treatment. |
