High levels of serum platelet-derived growth factor-AA and human epidermal growth factor receptor-2 are predictors of colorectal cancer liver metastasis

Table 1 Patient clinical and pathological characteristics n (%)

Clinical variable	Group A (n = 10)	Group B (n = 10)	P value
mean age (yr)	68 (41-79)	60 (30-73)	0.150
Male	6 (60)	4 (40)	0.625
pT stage			1.000
pT3	6 (60)	6 (60)
pT4	4 (40)	4 (40)
pN stage			0.168
pN0	0	1 (10)
pN1	0	3 (30)
pN2	4 (40)	6 (60)
Location			1.000
Right colon	4 (40)	4 (40)
Left colon/rectum	6 (60)	6 (60)
Histology differentiation			1.000
Well	2 (20)	2 (20)
Moderately	4 (40)	4 (40)
Poorly/mucinous	4 (40)	4 (40)
Lymphovascular invasion	6 (60)	4 (40)	0.625
Preoperative CEA (median, range)	1.74 (1.18-11.0)	9.64 (1.12-512.9)	0.017

Quantitative variables are represented as median (range); qualitative characteristics are represented as n (%). CEA: Carcinoembryonic antigen.

Table 2 Analyses of serum levels of factors between group A and group B in tumor drainage and peripheral veins

	Drainage blood			Peripheral blood
	Group A (non-metastatic)	Group B (metastatic)	P value	Group A (non-metastatic)	Group B (metastatic)	P value
RANTES (ng/mL)	52.61 ± 35.37	95.17 ± 70.21	0.104	36.34 ± 23.64	66.60 ± 25.55	0.013
EGF (pg/mL)	150.09 ± 70.40	270.67 ± 163.70	0.053	135.16 ± 67.01	289.36 ± 147.24	0.007
PDGFAA (ng/mL)	2.30 ± 0.80	4.62 ± 1.60	0.001	2.38 ± 0.85	3.99 ± 1.46	0.007
HER2 (ng/mL)	2.54 ± 0.68	2.95 ± 1.02	0.296	2.01 ± 0.55	2.91 ± 0.49	0.001
MMP7 (ng/mL)	2.77 ± 1.47	4.57 ± 2.70	0.080	2.20 ± 1.08	3.98 ± 2.10	0.028

Values are presented as mean ± SD. RANTES: Regulated on activation normal T cell expressed and secreted; EGF: Epidermal growth factor; PDGFAA: Platelet-derived growth factor AA; HER2: Human epidermal growth factor receptor 2; MMP7: Matrix metalloproteinase 7.

Table 3 Correlation between factor levels in peripheral and tumor drainage venous blood

Correlation	r	P value
dPDGFAA-pPDGFAA	0.794	< 0.001
dHER2-pHER2	0.189	0.424
dRANTES-pRANTES	0.705	0.001
dEGF-pEGF	0.605	0.005
dMMP7-mMMP7	0.863	< 0.001
pEGF-dPDGFAA	0.678	0.001
pEGF-pPDGFAA	0.887	< 0.001
pEGF-pHER2	0.489	0.029
pHER2-pMMP7	0.529	0.016

d means factors in drainage vein blood; p means factors in peripheral vein blood. RANTES: Regulated on activation normal T cell expressed and secreted; EGF: Epidermal growth factor; PDGFAA: Platelet-derived growth factor AA; HER2: Human epidermal growth factor receptor 2; MMP7: Matrix metalloproteinase 7.