Intensified Surveillance for Early Detection of Breast Cancer in High-Risk Patients

Efforts for early detection of breast cancer play an important role in the care of high-risk women. This will include both women with a pathological mutation in one of the known breast cancer susceptibility genes as well as women with a high breast cancer risk based on family history only. Due to the much higher incidence of breast cancer in premenopausal women with a genetic predisposition or a familial background, to be most effective, imaging-based breast surveillance should start at an age as early as 25-30 years. There is now ample evidence that magnetic resonance imaging (MRI) is by far the most sensitive imaging modality in young high-risk women. With high-risk multimodality screening at least 30% of breast cancers will be detected primarily by MRI and would have been missed at regular screening without MRI. Therefore, most high-risk breast surveillance programs now offer annual MRI to eligible high-risk women from age 25 to 30, usually supplemented by regular mammography starting at least from age 40. The inclusion of clinical breast exam (CBE) and/or ultrasound in the high-risk surveillance has little impact on the detection of additional cancers, but may improve compliance and reduce unnecessary callbacks for nonspecific findings on MRI. To reduce advanced stage interval cancers, especially in BRCA1/2 mutation carriers, some programs offer additional semiannual CBE and/or ultrasound or alternate MRI and mammography every 6 months. How long regular MRI should be continued in high-risk women is a matter of considerable debate. It appears feasible that MRI can safely be discontinued even in BRCA1/2 mutation carriers between the age of 60 and 70, especially if mammographic breast density is low. Even though several cohort studies have now demonstrated a very favorable stage distribution of breast cancers found in women undergoing high-risk surveillance with MRI, data on long-term survival and mortality in these patients is still rare.