Circulating Tumor DNA: A New Research Frontier in Urological Oncology from Localized to Metastatic Disease

Background and objective: Circulating tumor DNA (ctDNA) testing provides valuable prognostic and predictive information for guiding therapeutic choices and monitoring disease progression and drug resistance for urological tumors. Our review focuses on emerging opportunities for ctDNA analysis in urological tumors and the development of potential circulating biomarkers within a multidisciplinary framework to improve personalized treatment. Methods: A nonsystematic literature review was conducted in the PubMed and MEDLINE databases. Prospective and retrospective peer-reviewed studies, review articles, and research abstracts on the use of ctDNA for urological tumors were included. Key findings and limitations: Several studies have demonstrated that ctDNA analysis is a promising tool that can help clinicians in the diagnosis and clinical management of urological tumors. In prostate and urothelial cancers, the ctDNA fraction increases proportionally from localized to metastatic disease, indicating a higher tumor burden and more aggressive behavior. Thus, ctDNA seems to be a useful tool for improving prognostic risk stratification and treatment selection. Data on the use of liquid biopsy in renal cell carcinoma are still limited, and assessment of prognostic and predictive biomarkers is a critical unmet need. Conclusions and clinical implications: ctDNA analysis promises to revolutionize the management of urological tumors in different disease settings. Integration of ctDNA testing in routine clinical practice will require a multidisciplinary approach that involve patients, clinicians, and molecular biologists. Patient summary: We reviewed how testing for tumor DNA in blood (circulating tumor DNA, ctDNA) is used in urological cancers. A great deal of evidence supports the usefulness of this noninvasive test. However, further research via a multidisciplinary approach is needed before ctDNA testing becomes part of routine patient care.