Multiplex RT-PCR-based detections of CEA, CK20 and EGFR in colorectal cancer patients

Table 4 Analysis of the clinical and pathological characteristics in relation to the detection pattern of circulating tumor cells using the carcinoembryonic antigen, cytokeratin 20 and epidermal growth factor receptor multiplex assay n (%)

Parameter	No. of positive markers in each blood sample				P-value
	0	1	2	3
Age (yr)
< 69	1 (2.4)	7 (17.1)	26 (63.4)	7 (17.1)
≥ 69	3 (6.4)	8 (17)	26 (55.3)	10 (21.3)	0.963
Sex
Male	3 (5.4)	8 (14.3)	32 (57.1)	13 (23.2)
Female	1 (3.1)	7 (21.9)	20 (62.5)	4 (12.5)	0.294
Stage (Astler-Coller)
A + B	4 (13.3)	7 (23.3)	17 (56.7)	2 (6.7)
C	0 (0)	6 (22.2)	17 (63)	4 (14.8)
D	0 (0)	2 (6.5)	18 (58.1)	11 (35.5)	< 0.001
Lymph node involvement1
≤ 3	4 (7.1)	11 (19.6)	35 (62.5)	6 (10.7)
> 3	0 (0)	4 (16)	14 (56)	7 (28)	0.055
Tumor size (cm)2
< 3	2 (10.5)	2 (10.5)	15 (79)	0 (0)
3-5	1 (2.5)	8 (20)	21 (52.5)	10 (25)
> 5	1 (4.8)	5 (23.8)	11 (52.4)	4 (19)	0.774
Differentiation3
Well + moderate	4 (6.8)	10 (17)	36 (61)	9 (15.2)
Poor + no	0 (0)	4 (22.2)	10 (55.6)	4 (22.2)	0.560
Serum CEA (ng/mL)4
< 5	3 (10)	9 (30)	12 (40)	6 (20)
5-10	0 (0)	1 (7.1)	11 (78.6)	2 (14.3)
> 10	0 (0)	4 (13.3)	17 (56.7)	9 (30)	0.029

P-values were calculated by Spearman’s test.

¹P-value calculation using data from 81 patients (7 missing values);

²P-value calculation using data from 80 patients (8 missing values);

³P-value calculation using data from 77 patients (11 missing values);

⁴P-value calculation using data from 74 patients (14 missing values). CEA: Carcinoembryonic antigen.