Table 1.
Characteristics of study participants in a nested biopsy study within the Karolinska mammography project for risk prediction for breast cancer (Karma) (N = 153)
| Characteristics or histological markers | N | Mean (SD), range, or number (%) |
|---|---|---|
| Characteristic | ||
| Age at biopsy (y) | 153 | 57.2 (9.0), 41–76 |
| BMI (Kg/m2) | 151 | 25.5 (4.4), 18.9–44.8 |
| Age at menarche (y) | 145 | 13.1 (1.4), 9–17 |
| Age at first birth (y) | 126 | 26.3 (5.2), 17–46 |
| Age at menopause (y) | 79 | 50.6 (4.7), 35–59 |
| Parous status | 146 | |
| Nulliparous | 20 (13.7) | |
| Parous | 126 (86.3) | |
| Pregnancies (number) | 146 | 2.4 (1.6), 0–8 |
| Births (number) | 146 | 1.8 (1.1), 0–5 |
| Breastfeeding (months)a | 125 | 17.1 (10.1), 0–53 |
| Ever taken oral contraceptives | 144 | |
| No | 24 (16.7) | |
| Yes | 120 (83.3) | |
| Postmenopausal status | 150 | |
| Premenopausal | 55 (36.7) | |
| Postmenopausal | 95 (63.3) | |
| Ever taken hormone replacement therapy | 148 | |
| No | 106 (71.6) | |
| Yes | 42 (28.4) | |
| Benign breast disorder | 151 | |
| No | 111 (73.5) | |
| Yes | 40 (26.5) | |
| Tissue distribution and proteins markers | ||
| Epithelial area (%) | 153 | 3.7 (6.0), 0.0–34.2 |
| Stromal area (%) | 153 | 45.9 (28.9), 1.6–100 |
| Adipose area (%) | 153 | 50.4 (30.9), 0.0–98.4 |
| Epithelial Ki-67 (%) | 111 | 2.4 (2.6), 0.0–17.0 |
| Epithelial ER (%) | 110 | 30.4 (11.2), 4–56.8 |
| Epithelial PR (%) | 114 | 16.1 (12.9), 0–57.9 |
| Stromal Ki-67 | 112 | |
| Negative | 78 (69.6) | |
| Positive | 34 (30.4) | |
| Stromal ER | 112 | |
| Negative | 22 (19.6) | |
| Positive | 90 (80.4) | |
| Stromal PR | 122 | |
| Negative | 20 (16.4) | |
| Positive | 102 (83.6) | |
BMI body mass index, ER oestrogen receptor, IHC immunohistochemical, PR progesterone receptor, SD standard deviation, y years
aMinimum total duration of breastfeeding (months)