Functional promoter -765 G > C variant in COX-2 gene is associated with the susceptibility of breast cancer in Chinese Han women

Table 1 Distributions of select variables in breast cancer cases and cancer-free controls

Variables	Case (N = 465), %		Control (N = 799), %		P*
Age at diagnosis or recruitment (year)
Mean ± SD	52.0 ± 11.0		50.8 ± 13.2		0.110
<52	239	51.4	437	54.7	0.257
≥52	226	48.6	362	45.3
Age at menarche (year)
Mean ± SD	14.55 ± 1.84		14.89 ± 1.76		0.002
<14	136	29.3	183	22.9	0.012
≥14	329	70.7	616	77.1
Tumor size
Less than 2 cm	126	27.1
2 to 5 cm	310	66.7
More than 5 cm	29	6.2
LN involvement
Negative	251	54.0
Positive	214	46.0
ER
Negative	162	34.8
Positive	303	65.2
PR
Negative	209	44.9
Positive	256	55.1
HER-2
Negative	309	66.4
Positive	156	33.6

ER, estrogen receptor; PR, progestin receptor; LN, lymph node; HER-2, human epidermal growth factor receptor 2; *T-test or two-sided χ²-test.

ISSN: 1475-2867