Subbu Sundries — Recapping Recent Observations and Setting the Stage for This Week

Research evidence excerpt

Subbu Sundries — Recapping Recent Observations and Setting the Stage for This Week

DIAGNOSTICS & LIFE SCIENCES TOOLS

June 8, 2026

higher TF estimates predicting worse outcomes. The authors highlight that joint modeling

enables patient-specific, dynamically updated predictions that could support real-time

treatment decisions in mBC.

• 6/4: Methylation-based ctDNA monitoring in metastatic breast cancer during CDK4/6

inhibitor therapy; published in Nature Communications. In this analysis, GH investigators

and Princess Margaret Cancer Centre collaborators applied methylation-based tumor

fraction (mTF) measurement via Reveal across 350 serial plasma timepoints from 57

HR+/HER2- mBC patients on CDK4/6 inhibitor therapy. Baseline ctDNA was detected

in 94.7% of patients. mTF clearance on treatment was associated with prolonged

time to treatment discontinuation (HR=0.17, p<0.0001), and a rise in mTF (molecular

progression) preceded clinical treatment discontinuation by a median of 5.8 months.

Resistance-associated ESR1 and RB1 alterations frequently emerged at the time

of molecular progression. The mTF metric outperformed mutation-based tracking,

supporting prospective evaluation of mTF-guided treatment adaptation.

• 6/5: Donor-Derived Cell-Free DNA as a Prognostic Biomarker After Heart

Transplantation: The DEFINE-HT Study; published in JACC: Heart Failure. In this

prospective, observational study, NTRA and academic collaborators evaluated the

Prospera Heart assay in 110 heart transplant recipients across 10 US centers, following

patients for one year with dd-cfDNA collected during surveillance and during "for-cause

evaluations independent of clinical decision-making". The composite endpoint (treated