Detectability of residual invasive bladder cancer in delayed 18F-FDG PET imaging with oral hydration using 500 mL of water and voiding-refilling

2-Fluorine-18-fluoro-2-deoxy-d-glucose positron emission tomography (18F-FDG PET) imaging is not considered useful for assessing bladder cancer due to the physiological uptake of 18F-FDG in the bladder. Despite reports of the detection of bladder cancer by washing out 18F-FDG from the bladder, such methods are invasive and impractical in the routine practice. The purpose of this study was to evaluate prospectively the utility of oral hydration with 500 mL of water and voiding-refilling, a minimally invasive method that we introduced to enable detection of residual invasive bladder cancer on delayed 18F-FDG PET imaging.