Minimal Residual Disease (MRD) is the presence of a small number of malignant cancer cells that remain in the body after successful therapeutic intervention. MRD can persist at low levels in patients who may be in remission or not show any phenotypic symptoms. Detectable levels of MRD are a risk factor for recurrence, as the remaining cancer cells in the body can metastasize and proliferate over time. Although conventional surveillance technologies, such as radiographic imaging, are highly sensitive methods, the number of remaining cancer cells may be so small that they cannot be detected until symptoms of recurrence appear.
Monitoring MRD can be achieved with liquid biopsy, which enables diagnostic testing of blood or other bodily fluids. This approach has the potential to detect residual cancer cells earlier than standard surveillance methods, allowing for earlier therapeutic intervention. To do this, circulating tumor DNA (ctDNA) is utilized as a biomarker for liquid biopsy MRD testing. A common approach is to generate a variant profile of a patient’s primary tumor through whole-genome or whole-exome sequencing just prior to therapy. A subset of patient-specific variants is then selected from this primary tumor and a small target enrichment panel (MRD panel) is designed against these variants of interest. After treatment, repeated MRD testing will be used to monitor the disease recurrence of the patient at set time-intervals, so that a re-appearance of the selected ctDNA biomarkers in the blood can be evaluated.
The Twist Bioscience MRD Rapid 500 Panel is a scalable target enrichment solution for monitoring minimal residual disease that leverages Twist’s silicon based DNA synthesis platform to design and manufacture capture panels for personalized medicine. Twist’s proprietary design algorithms and a streamlined manufacturing pipeline enable design automation, synthesis, and rapid turnaround time of as few as 6 business days from the time of order. Cast a broader net to fully characterize adjuvant response at a genomic level with MRD panels ranging from 50 to 500 probes per panel and are compatible with Twist’s existing NGS library preparation and hybrid capture workflow.



