Table 1.

Definition of high risk

Risk factor	Defining high risk
First-degree family member diagnosed at <50 years of age	Twofold risk
Atypical hyperplasia	Cumulative absolute risk is 30 % at 25-year follow-up
Chest radiation between 10 and 30 years of age	40 % lifetime risk
Gail model 5-year risk	Five-year risk ≥1.7 %
Breast density (BI-RADS, D3 or D4)	Women with extremely dense breasts have a twofold increased risk compared with average women
Lobular carcinoma in situ	25 % lifetime risk
International Breast Cancer Intervention Study model (Tyrer–Cuzick model) life-time risk	≥20 % lifetime risk

BI-RADS Breast Imaging Reporting and Data System, D3 the breast tissue is heterogeneously dense, D4 the breast tissue is extremely dense