Table 1. Distributions of select variables in breast cancer cases and cancer-free controls.
| Characteristics | Cases | Control | P value* | |
|---|---|---|---|---|
| Number | 560 | 583 | ||
| Age (mean ± SD) | 49.09 ± 11.02 | 48.80 ± 8.28 | 0.612 | |
| Menopausal status | ||||
| Premenopausal | 264 | 281 | ||
| Postmenopausal | 296 | 302 | 0.716 | |
| Body mass index (kg/m2) | ||||
| (mean ± SD) | 22.52 ± 2.84 | 22.95 ± 3.21 | 0.038 | |
| Tumor size | < 2 cm | 188 | ||
| ≥ 2 cm | 372 | |||
| LN metastasis | Negative | 236 | ||
| Positive | 324 | |||
| ER | Negative | 247 | ||
| Positive | 313 | |||
| PR | Negative | 255 | ||
| Positive | 305 | |||
| Her-2 | Negative | 389 | ||
| Positive | 171 | |||
| Ki67 | < 14% | 195 | ||
| ≥ 14% | 365 | |||
*
T-test or two-sided χ2-test.
LN: Axillary lymph node; ER: Estrogen receptor; PR: Progesterone receptor; HER-2: human epidermal growth factor receptor 2.