Is it time to add liquid biopsy to imaging based response assessment?
Early identification of metastatic cancer response is critical for optimizing therapy and accelerating drug development, yet RECIST imaging-based criteria typically require 6–12 weeks and measurable disease. Emerging evidence shows that on-treatment changes in circulating tumor DNA (ctDNA) could help detect response or resistance earlier. To address this, the RECIST Working Group has reviewed current data and outlined priorities for integrating ctDNA into response evaluation, including standardized datasets, timing, assay thresholds, and regulatory considerations. Clinically meaningful ctDNA changes vary by cancer type and therapy, requiring rigorous validation before pan-cancer adoption. Despite these challenges, ctDNA offers a minimally invasive, promising complement to RECIST and a potential early endpoint for modern trials. Therefore, the RECIST Working Group is evaluating the available and required evidence to update RECIST.
Project leaders:
- Elena Garralda, VHIO, SE
