Challenges and proposed solutions to the adoption of cell free DNA in screening, detecting and prognosticating colorectal cancer

Table 1 Liquid biopsy kits analyzing cell free DNA

Name	Company	CfDNA source	Function	Detection of CRC sensitivity	Main limitation	Price per kit (dollar)
CancerSEEK	Thrive Earlier Detection Corp (Cambridge, Massachusetts, United States)	Plasma	Detection of 8 different cancers	64.0%	Low sensitivity for CRC detection	500
ColoAlert®	Pharm Genomics (Mainz, Germany)	Stool	Detection of CRC	84.6%	Low to very low certainty of reliable evidence available	151
Guardant360® CDx	Guardant Health (Palo Alto, California, United States)	Plasma	Genome profiling	NIL	Only some tumours shed detectable ctDNA into circulation	5000
FoundationOne® Liquid CDx	Foundation Medicine (Ontario, Canada)	Plasma	Genome profiling	NIL	Majority of the mutations detected are non-actionable	5800
Oncomine™ Colon cfDNA Assay	Thermo Fisher (Yokohama, Japan)	Plasma	Prognostication	78.6%	Low feasibility in clinical practise	12000
Signatera™	Natera (Austin, Texas, United States)	Plasma	Surveillance of MRD	99.9%	Not as sensitive as standard-of-care imaging surveillance	1750

cfDNA: Cell free DNA; CRC: Colorectal cancer; MRD: Minimal disease recurrence; ctDNA: Circulating tumour DNA.

Table 2 Liquid biopsy kits analyzing epigenetic changes

Name	Company	cfDNA source	Function	Detection of CRC sensitivity	Main limitation	Price per kit (dollar)
Cologuard®	EXACT Sciences Corporation (Madison, Wisconsin, United States)	Stool	Detection of CRC	92.3%	Poor compliance rate due to the inconvenience of collecting stool sample	649
Epi proColon®	Epigenomics AG (Berlin, Germany)	Plasma	Detection of CRC	74.0%	Large amount of blood plasma (> 3.5 mL) is required	192
ColoProbe	NIL	Plasma	Detection of CRC	82.7%	Performance could exhibit variability since age was shown to be a confounding factor	NIL
ColonSecure	NIL	Plasma	Detection of CRC	85.3%	Performance could exhibit variability since age was shown to be a confounding factor	NIL
Guardant Reveal™	Guardant Health (Palo Alto, California, United States)	Plasma	Surveillance of MRD	91.0%	High false-negative and high false-positive rates	5000

cfDNA: Cell free DNA; CRC: Colorectal cancer; MRD: Minimal disease recurrence.