CHICAGO, United States – May 6, 2026
Belay Diagnostics has announced new peer-reviewed clinical data demonstrating that its Belay Summit™ cerebrospinal fluid (CSF)-based liquid biopsy test informed clinical decision-making in 93% of cases involving suspected or confirmed central nervous system (CNS) cancers. The real-world study, conducted at UT Southwestern Medical Center and published in the journal Cancers, evaluated Summit across 123 specimens from 120 patients and showed that the test identified clinically significant molecular variants even in cases where standard cerebrospinal fluid cytology failed to detect malignancy. The findings highlight the growing importance of advanced liquid biopsy technologies in improving diagnosis, treatment selection, and disease monitoring for patients with complex CNS malignancies, including leptomeningeal disease.
Summit Detected Variants Missed by Standard Cytology
According to the study, standard CSF cytology was negative in 86% of patient specimens, underscoring the limitations of conventional diagnostic methods for CNS cancers. Despite negative cytology findings, Belay Summit identified clinically significant variants in 56% of cytology-negative cases, while also detecting variants in every cytology-positive sample. Researchers emphasized that Summit not only improved sensitivity but also provided molecular characterization capabilities unavailable through standard cytology.
This additional molecular information can help clinicians guide treatment decisions, select targeted therapies, and monitor disease progression more effectively. Importantly, the study also found that Summit’s performance appeared unaffected by corticosteroid use, a known factor that can interfere with traditional cytology accuracy in CNS cancer evaluations.
Quantitative Monitoring Supports Leptomeningeal Disease Management
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The study further demonstrated the value of Summit’s variant allele frequency (VAF) measurement capability, which provided quantitative insights into tumor burden and disease progression. All patient specimens with VAF levels above 5% were associated with confirmed leptomeningeal disease (LMD), including two cases initially believed to represent only parenchymal brain metastases.
Researchers also reported successful longitudinal monitoring in serial patient testing, where declining VAF levels corresponded with clinical improvement while stable VAF levels aligned with poor treatment response. These findings suggest that Summit could become an important tool not only for diagnosis but also for ongoing disease assessment and treatment monitoring in CNS oncology patients, an area where reliable biomarkers remain limited.
Summit 2.0 Expands Molecular Profiling Capabilities
Since completion of the study, Belay Diagnostics has launched Belay Summit™ 2.0, an expanded version of the platform designed to provide even broader molecular profiling for CNS malignancies. The updated assay evaluates 520 genes for SNVs and indels, 62 genes for copy number variants, and 28 genes for gene fusions, while also assessing tumor mutation burden (TMB) and microsatellite instability (MSI).
According to the company, Summit 2.0 delivers 96% clinical sensitivity and 98% specificity for CNS malignancies. The enhanced panel positions Belay Diagnostics competitively within the growing precision oncology and liquid biopsy market, particularly in neurologic cancers where tissue biopsies are often difficult or risky to obtain.
Growing Importance of Liquid Biopsy in CNS Oncology
Belay Diagnostics is part of a rapidly expanding segment of precision medicine focused on minimally invasive molecular diagnostics. The company’s CSF liquid biopsy platform, developed using technology licensed from Johns Hopkins University, aims to provide clinicians with comprehensive genomic insights using only a standard lumbar puncture, eliminating the need for invasive tissue sampling in many cases.
As CNS cancers remain among the most difficult malignancies to diagnose and monitor, technologies capable of improving early detection, molecular characterization, and treatment tracking are attracting increasing clinical and commercial attention. The latest study results strengthen the clinical value proposition for Summit and support broader adoption of liquid biopsy technologies in neuro-oncology practice.
Source: Belay Diagnostics press release
