Prognostic potential of ultrasensitive analysis of ctDNA dynamics across 24 solid cancer types treated with immunotherapy

A study at Vall d’Hebron Institute of Oncology (Barcelona, Spain) investigated the ability of ctDNA to predict progression-free and overall survival in a cohort of patients receiving immunotherapy for advanced cancer. Ultrasensitive ctDNA analysis, tracking approximately 1,800 tumor-specific mutations per patient, was carried out in a retrospective cohort (n=136) and a prospective validation cohort (n=66) across 24 cancer types. Analysis of 1,455 longitudinal samples revealed that ctDNA molecular response measured as early as 3 weeks after treatment initiation correlated with improved progression-free and overall survival, whereas ctDNA clearing at any time correlated with radiological response and prolonged survival. Additionally, ctDNA dynamics distinguished true progression from pseudoprogression and predicted outcomes in patients receiving continued immunotherapy beyond initial progression. The authors conclude that this study highlights the applicability of ultrasensitive DNA analysis across cancer types and immunotherapy modalities.