Promoter hypermethylation of the tumor-suppressor genes ITIH5, DKK3, and RASSF1A as novel biomarkers for blood-based breast cancer screening

Table 1 Clinicopathologic parameters of patients with breast cancer in the test and validation sets

Categorization	Test set (n^a = 112)	%	Validation set (n^a = 138)	%	Pvalue^b
Age at diagnosis					0.327
Median	60 years (range, 36-87 years)		63 years (range, 33-86 years)
Menopausal status					0.791
Premenopausal	22	19.6	21	15.2
Postmenopausal	90	80.4	117	84.8
Tumor size^c					0.337
pT1	49	43.8	67	48.6
pT2	51	45.5	59	42.8
pT3	8	7.1	8	5.9
pT4	2	1.8	2	1.4
Unknown	2	1.8	2	1.4
Lymph node status^c					0.997
pN0	55	49.1	77	55.8
pN1	38	33.9	42	30.4
pN2	9	8.0	10	7.2
pN3	7	6.3	6	4.3
Unknown	3	2.7	3	2.2
Histologic type					0.617
Invasive ductal	89	79.5	115	83.3
Invasive lobular	15	13.4	17	12.3
Other	8	7.2	6	4.2
Tumor grade^d					0.175
G1	6	5.4	14	10.1
G2	62	55.4	76	55.1
G3	44	39.3	48	34.8
Estrogen-receptor status^e					0.293
Negative (IRS0-2)	22	19.7	27	19.5
Positive (IRS3-12)	84	75.0	109	78.9
Unknown	6	5.4	2	1.4
Progesterone-receptor status^e					0.112
Negative (IRS0-2)	30	26.8	39	28.2
Positive (IRS3-12)	76	68.0	96	69.3
Unknown	6	5.4	3	2.2
HER2 status^f					0.112
Negative (0; 1+; 2+)	90	80.4	114	82.6
Positive (3+)	14	12.5	20	14.9
Unknown	8	7.1	4	2.9

^aOnly female patients with primary, unilateral, invasive breast cancer were included. ^bFisher Exact test at a two-sided significance level of 0.05. ^cAccording to TNM classification by Sobin and Wittekind [41]. ^dAccording to Bloom and Richardson, as modified by Elston and Ellis [42]. ^eIRS, immunoreactive score according to Remmele and Stegner [43]. ^fOverexpression for the HER2/neu gene was diagnosed analogous to the threshold of the DAKO-Score system based on IHC assay. Percentages may not sum to 100% because of rounding.