Table 2. Detection platforms for tumor-derived cfDNA in liquid biopsy.

Platforms	Advantage	Disadvantage	References
Single gene platform
Real-time PCR	Fast turn-around-time	Fairly sensitive. Difficult to detect <1% mutation level	(14-16,32,33)
	Streamlined workflow on validated platform	Only detect limited targets per assay
Digital PCR	Highly sensitive	In house-developed assay needs full validation	(17,18)
	Low running cost	Only detect limited targets per assay
Panel-based platform
Next-generation sequencing	Cost-effective. Screen of mutations in a panel of genes in a single assay	Long turn-around-time due to complex procedure	(34-36)
	Highly sensitive	Need to develop special data analysis pipeline for variant calling
		High running cost