Breast cancer risk factors used for 10-year breast cancer risk calculation with S-IBIS software
| Risk factor |
|---|
| Age (years) |
| Height |
| Weight |
| Age at menarche (years) |
| Age at first childbirth |
| Menopausal status |
| Hormone replacement therapy use |
| Benign breast disorder |
| Family history of breast cancer (breast cancer in first-and second-degree relatives and age at presentation) |
| Family history of ovarian cancer (ovarian cancer in first-degree relatives and age at presentation) |
Baseline characteristics of participants
| Breast cancer | Breast Centre | |
|---|---|---|
| group | group | |
| Age (yaars, mean)* | 45.6 | 44.8 |
| BMI, mean (kg/m2)* | 24.3 | 24.8 |
| Age at menarche (years, mean) | 13.0 | 13.0 |
| Nulliparity | 10.5% | 11.1% |
| Age at first childbirth (years, mean) | 23.0 | 23.4 |
| Positive family history for breast and/or ovarian cancer* | 48.8% | 56.6% |
Risk stratification for all participants and for age subgroups 40–44 years and 45–49 years based on S-IBIS calculation for breast cancer patients and women screened in Breast centre; risk categories for women aged 40 to 49 as in 2018 Slovenian guidelines
| Population risk (< 2 %) | Moderately increased risk (2–6.5 %) | High risk (> 6.5 %) | |
|---|---|---|---|
| Breast cancer group - 10-year breast cancer risk (age 40–49) | 60.8 % | 37.8 % | 1.4 % |
| Breast centre group - 10-year breast cancer risk (age 40–49) | 51.3 % | 47.6 % | 1.1 % |
| Breast cancer group - 10-year breast cancer risk (age 40–44) | 64.0 % | 34.4 % | 1.6% |
| Breast centre group - 10-year breast cancer risk (age 40–44) | 58.2% | 41.8 % | 0.0% |
| Breast cancer group - 10-year breast cancer risk (age 45–49) | 59.1 % | 39.7 % | 1.2 % |
| Breast centre group - 10-year breast cancer risk (age 45–49) | 46.1 % | 51.9% | 2.0% |