CT-DNA (Circulating Tumor DNA Test)

What is a CT-DNA test?

Most people with cancer have DNA derived from cancer cells circulating in their blood. In this Circulating Tumor DNA (CT-DNA) gene variants can occur that cause the tumor.

The CT-DNA test (also referred to as Liquid Biopsy) can be used in the follow-up of a patient-specific cancer treatment with designer molecules (personalized medicine).

The CT-DNA test can also diagnose many tumors in an early stage and is therefore recommended for people with an elevated risk to develop cancer.

GENDIA’s CT-DNA test detects +/- 2800 common gene variants in 50 oncogenes that cause many tumors (see Table 1).

The 50 cancer genes analysed in this test are (in alphabetical order): ABL1, AKT1, ALK, APC, ATM, BRAF, CDH1, CDKN2A, CSF1R, CTNNB1, EGFR, ERBB2, ERBB4, EZH2, FBXW7, FGFR1, FGFR2, FGFR3, FLT3, GNA11, GNAQ, GNAS, HNF1A, HRAS, IDH1, IDH2, JAK2, JAK3, KDR, KIT, KRAS, MET, MLH1, MPL, NOTCH1, NPM1, NRAS, PDGFRA, PIK3CA, PTEN, PTPN11, RB1, RET, SMAD4, SMARCB1, SMO, SRC, STK11, TP53, VHL.

Table 1: Frequency of gene variants in different cancers (%)

GENE	Lung		Intestine		Breast		Ovaria		Skin		Prostate		Pancreas
EGFR		30		50								3
TP53		34		45		23		46		12		14		36
KRAS		17		36				12				4		57
BRAF		1		11				7		45		1		2
PIK3CA		4		14		26		9				2		2
NRAS				4						18
CTNNB1				48				6		2-3		3		7
GNAS				2										16