SAGA Diagnostics Launches Pathlight MRD Test with 100% Sensitivity for Early Breast Cancer Detection
Key Insights
SAGA Diagnostics (search) announced the U.S. commercial launch of Pathlight (search), a first-of-its-kind multi-cancer (search) molecular residual disease platform initially indicated for early breast cancer (search).
Clinical validation study published in Clinical Cancer (search) Research demonstrated 100% sensitivity and 100% specificity with a 13.7-month lead time to recurrence across all breast cancer (search) subtypes and stages I-III.
The test uses structural variants (search) as biomarkers and combines whole genome sequencing with proprietary digital PCR technology to detect circulating tumor DNA from blood samples.
SAGA Diagnostics (search) announced the U.S. commercial launch of its Pathlight (search) test at the 2025 American Society for Clinical Oncology (ASCO) Annual Meeting, marking a significant advancement in molecular residual disease (MRD) detection for breast cancer (search) patients. The blood-based test demonstrated unprecedented clinical performance with 100% sensitivity and 100% specificity in detecting cancer (search) recurrence.
Revolutionary Technology Platform
Pathlight (search) represents a first-of-its-kind, multi-cancer (search) MRD platform that uses structural variants (search) (SVs) as biomarkers for cancer detection. These genomic alterations are well-established hallmarks of cancer, arising from and contributing to genomic instability and oncogenesis. The structural variants, including breakpoints and rearrangements, are highly tumor- and patient-specific, making them informative biomarkers for tracking disease progression.
The technology combines whole genome sequencing with proprietary algorithms and informatics optimized for identifying stable SV breakpoints. This process generates a personalized genomic fingerprint for each tumor, which is subsequently validated and tracked using proprietary multiplex digital PCR to enable rapid, precise, and quantitative MRD detection from a simple blood draw.
Clinical Validation Results
The clinical validity of Pathlight (search) was established through the TRACER (cTdna evaluation in eaRly breAst canCER (search)) study, published in Clinical Cancer (search) Research in January 2025. This retrospective analysis examined 100 patients with stage I–III breast cancer of all subtypes receiving standard-of-care neoadjuvant and adjuvant therapy.
The study results demonstrated best-in-class clinical performance with 100% sensitivity and 100% specificity, along with a 13.7-month lead time to recurrence as confirmed by clinical presentation or imaging. Notably, Pathlight (search) achieved a 96% baseline detection rate overall and 94% in estrogen receptor-positive (ER+) breast cancer (search), suggesting clinical advantages over first-generation ctDNA assays.
The test's sensitivity breaks the 1ppm barrier, offering the potential to detect MRD at the earliest possible opportunity to support individualized intervention directed towards cure.
Addressing Critical Clinical Need
"The vast majority of breast cancer (search) patients are diagnosed with ER+ disease, and up to 25% will experience recurrence – often many years after completing curative-intent treatment," said David Cescon, MD, PhD, medical oncologist and clinician scientist at Princess Margaret Cancer Centre, University Health Network and senior author of the paper. "We know that continued improvement in outcomes for people diagnosed with early breast cancer will require a shift towards more individualized treatment. There is a critical need for MRD testing that is both ultra-sensitive and ultra-specific, to enable long-term surveillance and risk-aligned treatment decisions for each patient."
Market Access and Clinical Implementation
Pathlight (search) has been submitted for U.S. reimbursement via the MolDX Program and is analytically validated across multiple cancer (search) types. The test is already being utilized in clinical studies by top pharmaceutical companies and at preeminent academic institutions and national cancer centers.
"By tracking structural variants (search) — stable, unique, and tumor-defining fingerprints of each patient's cancer (search) — Pathlight (search) enables interception of recurrence at its most treatable and potentially curable stage," commented Roopom Banerjee, Executive Chairman of SAGA Diagnostics (search). "Our goal is to deliver the most accurate, trusted results that provide assurance and support confident, informed treatment decisions."
Expanding Research Applications
SAGA Diagnostics (search) and its collaborators are presenting three abstracts at ASCO highlighting Pathlight (search)'s performance across multiple cancer (search) types, including breast cancer (search), ovarian cancer (search), and soft-tissue sarcoma (search). These presentations demonstrate the platform's potential for broader oncological applications beyond its initial breast cancer indication.
The company's CLIA-certified laboratory is located in Research Triangle Park, North Carolina, positioning SAGA Diagnostics (search) at the center of the life science ecosystem as it continues to develop partnerships with pharmaceutical and biotechnology companies for early through late-stage cancer (search) development programs.