ctDNA Monitoring Provides PFS Data for Patients With Metastatic RCC

Previous studies have shown that tumor-informed circulating tumor DNA (ctDNA) can improve clinical outcomes as an effective biomarker for treatment response monitoring (TRM) across various tumor types. 

A recent retrospective analysis has longitudinally examined ctDNA status and dynamics throughout surveillance and during TRM in patients with metastatic clear cell renal cell carcinoma (ccRCC) and non-clear cell RCC (nccRCC) treated with immunotherapy or targeted therapies. 

The multicenter study used real-world data from commercial ctDNA testing, and clinical data were collected on International Metastatic RCC Database Consortium (IMDC) risk category, pathologic subtype, and grade. 

The study analyzed 92 patients and 490 plasma samples of clear cell and non-clear cell histologic subtypes (ccRCC: 79.3%; nccRCC: 14.1%; unclassified: 6.5%). The majority of patients were grouped into the IMDC intermediate-risk category (69 of 92, 75%). 

With a median follow-up of 10 months (range, 4.2–25.8), ctDNA dynamics were analyzed in 56 patients during treatment. Circulating tumor DNA status was analyzed in a surveillance cohort consisting of 32 patients. 

Serial ctDNA negativity or clearance was linked to improved progression-free survival (PFS) compared with persistent ctDNA positivity during treatment (hazard ratio [HR], 3.2; P=.012). 

In the surveillance cohort, patients with positive ctDNA longitudinally experienced significantly inferior PFS (HR, 18; P=.00026) compared with patients who were serially negative. 

Serial ctDNA monitoring can provide important prognostic data for patients undergoing treatment or surveillance. These findings show high concordance between ctDNA status and resulting clinical outcomes.