Saga Diagnostics' Pathlight molecular residual disease (MRD) assay received positive Medicare reimbursement coverage through the MolDx program, allowing surveillance in stage II-III breast cancer patients with all subtypes, including HR+/HER2-, HER2+, and triple-negative disease. The blood-based test, launched in May 2025, employs whole-genome sequencing of tumor tissue to identify personalized structural variant signatures detected via digital PCR in circulating tumor DNA, achieving high sensitivity, specificity, and early recurrence detection compared to conventional imaging. This decision marks a significant step toward wider clinical adoption of MRD testing for personalized cancer management.