Future Directions for Circulating Tumor DNA Studies in Renal Cell Carcinoma

Circulating tumor DNA (ctDNA) is a minimally invasive biomarker that has attracted significant attention for its prognostic and predictive roles in oncology. In renal cell carcinoma (RCC), ctDNA profiling has revealed shorter ctDNA fragments and greater variability in ctDNA levels that are influenced by disease biology, tumor burden, timing, and tumor growth. Advanced detection methods, such as tumor-guided plasma analysis and methylation profiling, have enhanced sensitivity but require standardization. Emerging evidence highlights the prognostic potential of ctDNA, which correlates with worse outcomes in persistent or preoperative ctDNA positivity, advanced stage, and tumor burden. ctDNA dynamics align with therapeutic responses, and ctDNA profiling can reveal genomic alterations associated with resistance (eg, TP53, TERT) and responsiveness (eg, NF1, PIK3CA), and rare actionable mutations (eg, HER2, EGFR, BRCA1, ALK fusions). Despite limitations such as discordance in isolated intracranial progression, ctDNA complements tissue-based next-generation sequencing and facilitates real-time tumor monitoring and tracking of clonal evolution, and can guide personalized treatment strategies to improve patient outcomes. PATIENT SUMMARY: A blood test called circulating tumor DNA (ctDNA) can help doctors in monitoring cancer progression and predicting how well treatments might work. In kidney cancer, this test can detect tumor changes, guide personalized treatments, and predict outcomes earlier than traditional scans.