A multicenter study published in Clinical Cancer Research shows Personalis’ NeXT Personal whole‑genome, tumor‑informed MRD assay predicted early immunotherapy responses and survival across metastatic solid tumors. Investigators found ctDNA drops of ~30% before cycle two correlated with improved progression‑free and overall survival; ctDNA clearance produced a median three‑fold PFS gain and durable MRD negativity portended 100% OS in a subset. Separately, Droplet Biosciences validated postoperative lymph fluid as a sensitive sample type for detecting molecular residual disease in head‑and‑neck cancer, outperforming same‑day plasma for locoregional relapse detection. Together the results strengthen ctDNA’s clinical utility for early response assessment and postsurgical MRD surveillance, potentially shifting sample collection strategies and monitoring timelines in oncology trials.