Cancer monitoring and stratification: Enhancing the sensitivity of detection of ctDNA in early and late-stage disease

Recent studies have shown that circulating tumour DNA (ctDNA) can be used as a non-invasive liquid biopsy to monitor tumour dynamics, detect minimal residual disease, and stratify patients to targeted treatment. This talk will focus on the development and application of methods for ctDNA analysis ranging from digital PCR through shallow whole genome sequencing (sWGS) and ultrasensitive targeted sequencing approaches. These have been applied to detect and characterise ctDNA and to monitor disease burden in advanced and early stage cancer, including in high-grade serous ovarian, melanoma, breast and non-small cell lung cancer (NSCLC). Methods have been validated for clinical application for molecular stratification and therapy selection in patients with advanced cancers. In addition, work will be presented demonstrating that incorporation of ctDNA size fragmentation features can enhance sensitivity of detection.