Together, we can transform the future of cancer care.
Tracking early stage breast cancer with ultrasensitive ctDNA
Information for patients with breast cancer
Monitoring therapy response with ultrasensitive ctDNA across cancer types
Ultrasensitive ctDNA detection in early-stage lung cancer
Personalis is transforming the development of next-generation therapies.
Detection of residual cancer via liquid biopsy is an essential part of the next generation of cancer management. Personalis has developed a whole-genome based, patented-approach to highly sensitive molecular residual disease (MRD) detection and quantification. As shown in Figure 1, higher sensitivity is essential for detection of disease in indications where ctDNA or tumor-variant levels are limited such as low shedding or low TMB cancers.
Figure 1: Post-baseline plasma samples across different cancer types and stages demonstrates range of tumor signal. LOD at 100 PPM excludes 48% of cases in cohort. LOD at 10 PPM excludes 20% of cases in cohort.
The key to our industry-leading sensitivity is our patented whole-genome-powered tumor-informed approach to detecting MRD. Our proprietary methods involve sequencing up to 1,800 variants of the highest value specific to each patient, enabling us to detect infinitesimal traces of residual cancer.
Figure 2: Tumor and normal (T/N) whole genome sequencing (WGS) unlocks the entire genomic footprint, enabling inclusion of a greater number of variants in the panel vs. T/N whole exome sequencing (WES) approaches.
More specifically, this approach leverages the broad array of SNVs detected with >30x WGS coverage of a patient’s tumor (and accompanying normal) as shown in Figure 3. Going beyond whole-exome based approaches, we utilize patient specific SNVs from non-coding regions of the genome to increase the number of variants included in making MRD calls. This enables higher sensitivity to detect MRD at nascent stages.
Figure 3: The panel design and plasma sequencing process leverages tumor and normal samples from a patient to build a highly personalized panel for longitudinal tracking.
Note: T = sampling timepoint
Tissue WGS often yields tens of thousands of mutations, many in inherently noisy regions. Personalis has extensive experience with WGS and is uniquely positioned to maximize genomic data while cutting through the noise. Our advanced, proprietary statistical analyses distinguish signal from noise for each individual patient panel and sample. The powerful combination of WGS to enable target breadth, coupled with robust error and noise reduction algorithms, results in industry-leading MRD sensitivity in the 1 – 3 parts-per-million (PPM) range with ≥99.99% specificity.
