Catheter-assisted 18F-FDG-PET/CT imaging of primary bladder cancer

OBJECTIVE: The purpose of this study was to prospectively investigate the value of a standardized 18F-fluorodeoxyglucose (18F-FDG)-PET/computed tomography (CT) protocol for imaging of primary bladder cancer, using standardized bladder flushing and filling. METHODS: We included 19 patients with cT1-4 bladder cancer. A Foley catheter was inserted before 18F-FDG injection. PET/CT imaging was performed according to four bladder protocols: (1) bladder empty; (2) bladder empty after flushing; (3) bladder filled with 50 ml saline; and (4) bladder filled with 100 ml saline. Tumour visibility was assessed and compared with histopathology or CT and cystoscopy. RESULTS: The procedure was successfully completed in 16 out of 19 patients. The reference standard revealed a bladder tumour in 16 out of 19 patients. Sensitivity of protocols 1 and 2 was 0.38 [95% confidence interval (CI), 0.16-0.64] compared with 0.63 (95% CI, 0.36-0.84) for protocols 3 and 4. CONCLUSION: Flushing and subsequent retrograde filling of the bladder results in the highest rate of tumour visualization and quantification. Flushing alone is inferior.