Abstract

The Promise of Liquid Biopsies to Precision Medicine

Richie Soong, Senior Principle Investigator, National University of Singapore

Precision medicine is an emerging healthcare model of providing person-centred care based on an understanding of individual predisposition and specific features of their health condition. Evidence is accumulating that suggests that precision medicine can provide health benefits beyond conventional ‘one-size-fits-all’ healthcare approaches. Prominent examples including the testing for BRCA1/BRCA2 mutations for predicting breast and ovarian cancer risk, tumour HER2 amplification for predicting response to anti-HER2 antibodies, tumour EGFR sequencing for predicting response to EGFR tyrosine kinase inhibitors, and tumour PD-L1 expression for immune checkpoint inhibitors. Liquid biopsies - the analysis of bodily fluids, such as blood, to detect condition-specific features, such as DNA mutations - has emerged as a promising new tool for precision medicine. Of new value, liquid biopsies present the possibility of being able to monitoring the progress of a condition or treatment response through multiple sampling over time. They also provide the opportunity to gain insights into the condition where conventional tissue biopsies are difficult to obtain. The leading example of this is the detection of EGFR T790M mutations to assess likely response to third-generation EGFR inhibitors in non-small cell lung cancer (NSCLC) patients that have experienced disease recurrence following treatment with first-generation EGFR inhibitors. Recently, liquid biopsies have also started to be used to expediently detect EGFR mutations predictive of first-generation EGFR inhibitor response at NSCLC diagnosis while tissue assessment proceeds. This presentation will cover our experience in implementing precision medicine in Asia, and systematically assessing the analytical and pre-analytical steps in digital droplet PCR and next generation sequencing analysis of liquid biopsies.