Liquid biopsy for gastric cancer: Techniques, applications, and future directions

Table 2 Liquid biopsy and early detection of gastric cancer. Summary of the main published studies[146-148]

Role	Structure	Approach	Accuracy	Findings/challenges
Diagnosis	CTCs	Count	S: 42-85%; E: 90%-99%	Low sensitivity; diverse cutoffs
		CD44+	S: 92%; E: 100%	Small sample size
	cfDNA/ctDNA	Methylation	S: 50%-69%; E: 75%-92%	Diverse markers
		Quantification	S: 79%-96%; E: 91%-94%	Diverse methodology
	RNA	MiRNA	S: 67%-99%; E: 66%-95%	Diverse markers
		CircRNA	S: 78%-89%; E: 45%-84%	Diverse markers
		LncRNA	S: 65%-84%; E: 53%-87%	Diverse markers
	EVs RNA	MiRNA	S: 26%-95%; E: 56%-100%	Up or down expression; diverse markers
		CircRNA	S: 41%-87%; E: 68%-98%	Down expression; diverse markers
		LncRNA	S: 70%-88%; E: 60%-98%	Up expression; diverse markers
	Proteins	TTF1-3, CDH17, TFF3, and TXNRD1	S: 62%-96%; E: 57%-83%	Diverse markers; panels

CTC: Circulating tumor cells; S: Sensitivity; E: Specificity; EV: Extracellular vesicle.