Minimal Residual Disease (MRD) has emerged as a key focus in precision oncology. MRD refers to residual cancer cells or biomarkers remaining after treatment, often too few to detect using traditional methods. Circulating tumor DNA (ctDNA) is the most widely used biomarker for solid tumors, and ctDNA-MRD is rapidly gaining traction in cancer diagnostics and treatment.
Clinical applications of ctDNA-MRD now include postoperative treatment guidance and prognosis assessment for early- and mid-stage cancer patients. In November 2021, Professor Liu Lunxu’s team at West China Hospital of Sichuan University, in collaboration with Genecast Biotechnology, showed in the LUNGCA-1 study (330 NSCLC patients) that perioperative ctDNA can predict postoperative relapse, with ctDNA-MRD positivity serving as an independent risk factor for reduced recurrence-free survival. Adjuvant therapy improved outcomes in MRD-positive patients.
On May 14, a large-scale prospective MRD study in lung cancer led by Professor Wu Yilong, with Guangdong Provincial People’s Hospital and Geneplus-Beijing Institute, was published in Cancer Discovery. The study defined a potentially cured population with high negative predictive value and identified a high-risk period (12–18 months post-surgery) for conversion to MRD-positive status in stage II/III lung cancer patients.
The FDA has issued draft guidance on using ctDNA for early-stage solid tumor drug development, enabling ctDNA to serve as a stratification factor or early endpoint in clinical trials.
Two main ctDNA-MRD assay approaches exist: tumor-informed assays, which sequence tumor tissue and track specific variants, and tumor-naïve/agnostic assays, using fixed panels often combined with multi-omics techniques. In China, population-based fixed panels are increasingly applied for clinical companion diagnostics and MRD monitoring. Sequencing can be performed with MGI’s DNBSEQ-400* and DNBSEQ-T7*.
MGI’s DNBSEQ™ technology is particularly suitable for high-depth sequencing of low-concentration and complex samples like ctDNA. It reduces costs, ensures high data utilization, and supports a complete workflow from whole exome sequencing (WES) to customized panels and MRD monitoring. The ATOPlex Platform enables tumor WES, personalized panel design, production, quality inspection, and ctDNA-MRD tracking.
MGI continues to collaborate with partners to develop innovative MRD products and expand clinical adoption. On May 19, MGI and Genecast Biotechnology hosted an expert seminar in South China on ctDNA-MRD, discussing postoperative treatment guidance, early-stage NSCLC screening, and clinical application strategies.
StandardMPS and CoolMPS sequencing reagents and sequencers may be unavailable in certain countries.
