Table 1 Population characteristics
Characteristic | Category | Proportion (%) | Number of subjects |
|---|---|---|---|
Race | Caucasian | 84.3 | 177 |
African-American | 11.9 | 25 | |
Other | 3.8 | 8 | |
Age at menarche (years) (mean [standard deviation]) | Known | 12.7 [1.6] | 208 |
Unknown | 3 | ||
Use of oral contraceptives | Ever | 50.0 | 105 |
Never | 50.0 | 105 | |
Pregnancy history | ≧1 full term pregnancy | 88.6 | 186 |
No full term pregnancies | 11.4 | 24 | |
Age at first full term birth (years) (mean [standard deviation]) | Known | 24.9 [5.8] | 183 |
Unknown | 3 | ||
Menopausal status | Premenopausal | 11.9 | 25 |
Perimenopause | 5.2 | 11 | |
Postmenopausal | 76.2 | 160 | |
Unknown | 6.7 | 14 | |
Age at menopause (years) (mean [standard deviation]) | 48.8 [6.2] | 160 | |
Age at diagnosis | ≤60 years | 62.8 | 132 |
>60 years | 34.8 | 73 | |
Unknown | 2.4 | 5 | |
Tumor size | ≤2 cm | 47.1 | 99 |
>2 and ≤4 cm | 16.7 | 35 | |
>4 cm | 10.9 | 23 | |
Unknown | 25.2 | 53 | |
Tumor grade | 1 | 21.4 | 45 |
2 | 36.2 | 76 | |
3 | 23.8 | 50 | |
Unknown | 18.6 | 39 | |
Estrogen receptor status | Positive | 42.4 | 89 |
Negative | 22.9 | 48 | |
Unknown | 34.8 | 73 |