Urinary Cell-Free DNA Liquid Biopsy for Urothelial Cancer Diagnosis and Origin Identification

Urothelial carcinoma is the most common cancer of the urinary system. It includes bladder cancer and upper urinary tract cancer, which starts in the kidney pelvis or ureter. Doctors currently tell these types apart mainly by using invasive tests such as cystoscopy or ureteroscopy. These tests can be uncomfortable and may miss some tumors. This study is testing whether a urine sample can offer a simpler, non-invasive way to detect urothelial cancer and identify where the cancer started. This is a prospective, multicenter, observational study. It plans to enroll 477 adults, including 159 patients with upper urinary tract urothelial cancer, 159 patients with bladder cancer, and 159 people without cancer. Participants will provide a midstream urine sample of about 30 mL using a special collection tube. No experimental drug or device will be given. Participants will receive their usual medical care. The urine samples will be sent to a central laboratory. Researchers will extract cell-free DNA, which are small pieces of DNA released by cells into the urine. They will then perform low-pass whole-genome sequencing and study DNA fragment patterns, called fragmentomics. Machine learning will be used to build models that may help detect urothelial cancer and distinguish upper urinary tract cancer from bladder cancer. The study will also explore whether these urine DNA patterns are related to tumor stage and grade. The results may help develop a convenient urine-based test for patients in the future.

Inclusion Criteria: Age ≥18 years at the time of enrollment. Participants must have hematuria and be undergoing evaluation for urothelial carcinoma. Cases: Histopathologically confirmed primary urothelial carcinoma of the bladder, renal pelvis, or ureter, with no prior anti-tumor treatment, including transurethral surgery, radical surgery, systemic or local chemotherapy, radiotherapy, or immunotherapy. Controls: No tumor or suspected space-occupying lesion confirmed by systematic examination, including urinary ultrasound or computed tomography. Complete clinical and pathological data available, including tumor location, stage, and grade for cases. Willingness to provide urine samples. Written informed consent obtained. Exclusion Criteria: History of malignant tumors at other sites. Blood transfusion within 7 days before urine sampling. History of organ transplantation or allogeneic hematopoietic stem cell transplantation. Any severe systemic disease, acute infection, or other condition that, in the investigator's judgment, may affect sample quality or study participation.