Urinary bladder cancer is a common urological cancer. Although flexible cystoscopy is widely employed in bladder cancer detection, it is expensive, invasive, and uncomfortable to the patients. Recently, urinary cell-free DNA (ucfDNA) isolated from urine supernatant has been shown to have great potential in bladder cancer detection and surveillance. Molecular features, such as integrity and concentration of ucfDNA, have been shown to be useful for differentiating bladder cancer patients from healthy controls. Besides, bladder cancer also exhibits unique genetic features that can be identified from sequencing and expression of ucfDNA. Apart from bladder cancer detection, ucfDNA is also useful for molecular classification. For example, ucfDNA exhibits significant differences, both molecularly and genetically, in non-muscle-invasive and muscle-invasive bladder cancers. There is no doubt that ucfDNA is a very promising tool for future applications in the field of bladder cancer.
