Diagnostic value of 18F-FDG PET/CT delayed imaging after diuresis in patients with primary bladder tumor / 中华核医学与分子影像杂志

ABSTRACT

Objective To explore the diagnostic value of 18F-FDG PET/CT delayed imaging after induced diuresis for primary bladder tumor.Methods Fourteen patients (12 males,2 females; age range 35-88 years) with pathologically confirmed primary bladder tumor (clinical stage T1.3N0M0) were retrospectively analyzed.All patients underwent standard 18F-FDG PET/CT followed by a delayed (2.5-3.0 h later)pelvic imaging post intravenous injection of 20 mg furosemide and oral intake of 600 ml water.A positivelesion was defined as the uptake of 18F-FDG greater than the urine radioactivity and negative as equaled to or less than the urine radioactivity.Diagnostic efficacy of 18F-FDG PET/CT was calculated with pathology as the gold standard.Mann-Whitney u test was used to analyze data.Results There were 12 malignant (11 urothelium carcinomas and 1 squamous cell carcinoma) and 2 benign tumors (papillary epitheliomas).On standard PET/CT imaging,3 of 12 malignant lesions showed increased metabolism of 18F-FDG and the other 9 were false negative; while the 2 benign tumors showed no abnormal 18F-FDG uptake.The sensitivity,specificity,and accuracy of 18F-FDG PET/CT were 3/12,2/2 and 5/14,respectively.Sizes of the 3 18F-FDG-avid malignant lesions were greater than those of other 9 18F-FDG-negative lesions (26,30,35 mm vs (15.6±6.3) mm; Z=-2.315,P＜0.05).The sensitivity,specificity,and accuracy of delayed pelvic imaging were 11/12,2/2,13/14,respectively.Conclusion 18F-FDG PET/CT delayed imaging after diuresis has a high diagnostic efficacy for primary bladder tumor.