RaDaR is a tumor-informed liquid biopsy test for the detection of minimal or molecular residual disease (MRD). RaDaR can be utilized for patients with lung cancer, breast cancer, colon cancer and head and neck squamous cell carcinoma (HNSCC).
A unique RaDaR panel is built for each patient, specific to their tumor’s mutation profile, as determined by tumor tissue whole exome sequencing. Each panel includes up to 48 tumor-specific variants. A patient’s RaDaR panel can be utilized repeatedly over time to test for the presence or absence of tumor DNA (ctDNA) in a peripheral blood sample.
Studies in lung cancer, breast cancer, colon cancer and head and neck squamous cell carcinoma (HNSCC) have demonstrated that ctDNA detection following surgery or therapy is associated with increased risk of disease relapse in the absence of further treatment. Patients for whom ctDNA is not detected are at lower risk for relapse.
Serial sampling has been shown to improve clinical sensitivity for ctDNA recurrence detection as disease burden and associated ctDNA levels rise approaching clinical recurrence. Studies in lung cancer, breast cancer, colon cancer and HNSCC have indicated through serial sampling of patient plasma that ctDNA can be detected in advance of clinical relapse detected by radiographic imaging/scanning. However, a negative ctDNA result does not definitively indicate the absence of cancer as not all recurrences shed sufficient ctDNA to be detected.
Studies across multiple tumors have also demonstrated that ctDNA dynamics correlate with response to therapy and disease burden and can be predictive of patient outcomes.
References: PMIDs: 35306155, 26311728, 27384348, 31621801, 35132238, 3565732, 34001194, 35658506, 31369045, 34505064 and 36732628
RaDaR panel design and development:
- FFPE solid tumor tissue: Minimum surface area 20mm2 with ≥20% tumor content. Tissue depth should be ≥50 microns. Please use positively-charged slides and 10% NBF fixative. Do not use zinc fixatives.
- Paraffin block: Preferred
- Cut slides: Send ≥10 unstained sections cut at 5-10 microns plus one H&E slide
RaDaR plasma cfDNA analysis:
- Peripheral blood: two x 10 mL Streck Cell-Free DNA BCT® tubes
- RaDaR panel design and development: 4 weeks
- RaDaR plasma cfDNA analysis: 7 days