Identification of serum proteins discriminating colorectal cancer patients and healthy controls using surface-enhanced laser desorption ionisation-time of flight mass spectrometry

Table 1 Classification trees generated with the Biomarker Patterns Software

Tree	Included m/z’s (×103 Da): cut-off intensity values and class assignment				Sensitivity (%)	Specificity (%)
	Node 1	Node 2	Node 3	Node 4
I	3.3 ≤ 15.035 Colorectal cancer	-	-	-	77.8	73.3
II	28 ≤ 1.558 Colorectal cancer	4.5 ≤ 29.791 to Node 3	3.1 ≤ 9.866 to Node 4	6.6 ≤ 33.233 Colorectal cancer	77.8	73.3
III	3.3 ≤ 12.757 Colorectal cancer	-	-	-	66.7	83.3
IV	3.3 ≤ 12.757 Colorectal cancer	28 ≤ 1.285 Colorectal cancer	-	-	75.0	83.3
V	3.3 ≤ 12.981 Colorectal cancer	4.5 ≤ 28.599 Healthy control	-	-	84.2	83.3
VI	28 ≤ 1.529 Colorectal cancer	4.5 ≤ 28.577 to Node 3	6.6 ≤ 44.685 Colorectal cancer	-	89.5	88.9

Sensitivities and specificities for trees I to IV were obtained by blinded testing with data from the remaining sample set.

Table 2 BMW expression differences of colorectal cancer biomarkers in other tumors

Group	3.1×103 Da		3.3×103 Da		4.5×103 Da		6.6×103 Da		28×103 Da		5.9×103 Da
	Intensity	P (×10-3)	Intensity	P (×10-3)	Intensity	P (×10-3)	Intensity	P (×10-3)	Intensity	P (×10-3)	Intensity	P (×10-3)
HC (n = 20)	5.51 (2.4)		14.9 (4.73)		20.6 (9.16)		52.1 (7.4)		2.73 (1.25)		7.26 (4.23)
CRC (n = 17)	7.95 (4.64)	211	9.05 (3.81)	1.11	25.5 (5.99)	12.4	37.6 (9.17)	0.0388	1.44 (0.65)	0.801	10.84 (7.66)	161
BC (n = 10)	8.87 (2.59)	1.13	11.51 (3.4)	103	19.44 (8.16)	538	42.7 (7.58)	5.59	1.44 (0.59)	3.69	4.51 (2.55)	43.0
NSCLC (n = 8)	5.00 (2.93)	508	7.93 (3.38)	2.27	25.1 (7.93)	93.3	30.9 (11.2)	0.205	0.942 (0.45)	0.450	1.91 (2.13)	0.305
OC (n = 10)	7.29 (3.77)	218	9.89 (2.52)	3.69	27.7 (8.67)	27.8	40.6 (8.65)	2.07	1.31 (0.45)	0. 968	2.98 (1.47)	1.32
PC (n = 10)	7.65 (3.25)	131	9.59 (4.35)	7.21	29.6 (10.1)	18.4	36.5 (11.5)	0.967	1.26 (0.56)	1.35	2.73 (2.01)	1.86

For each m/z value, mean peak intensities (SD) are given with their P-values for the intensity difference with healthy controls (HC). BC: breast cancer; NSCLC: non-small cell lung cancer; OC: ovarian cancer; PC: prostate cancer.