AnteBC is a personalised breast cancer risk prediction test. This comprehensive test combines genetics, a polygenic risk score and high-risk monogenic variants with reproductive factors, familial and lifestyle data. It provides personalised medical information of the risk of breast cancer and offers recommendations for prevention and early detection.

Who can benefit from AnteBC?

AnteBC is suitable for women aged 25–80 who have European ancestry.

How frequent is breast cancer?

Breast cancer is the most common form of cancer in women. In the 28 European Union (EU) member states, more than 400,000 diagnoses are expected in 2018. These diagnoses account for 13.5% of all new cancer cases, and 29% of cases among women. Breast cancer is also one of the leading causes of cancer morbidity among women with around 100,000 yearly events that account for 16% of all female cancer deaths.

Genetics behind breast cancer?

Hereditary factors explain around a third of the risk of breast cancer. Genetic and biological factors underpin the familial clustering of breast cancer cases. The presence of a BRCA1 or BRCA2 mutation accounts for the majority of hereditary breast cancer cases. Genetic susceptibility to breast or ovarian cancer is also associated with mutations in other genes, such as ATM, CHEK2, TP53, PTEN, STK11, CDH1, PALB2, NBN, NF1 and BARD1.

Currently the largest genome-wide association study for breast cancer, which includes hundreds of thousands of people of European ancestry, has identified almost 180 single-nucleotide polymorphisms (SNPs) that are considered to describe around 18% of the familial relative risk. The polygenic risk score (PRS), part of the AnteBC test, includes these associated SNPs. Although individually associated SNPs may confer only a moderate risk of disease, the combined effect of all known associated SNPs can substantially influence breast cancer risk. Women can be divided into different risk categories for breast cancer based on polygenic risk score values.

What are the other risk factors for breast cancer?

The primary risk factor for breast cancer is age, as disease incidence begins to increase rapidly from the age of 45. Other important risk factors are genetic predisposition, family history, reproductive history, menstrual and childbearing history, breast density, oestrogen replacement therapy, race/ethnicity, and lifestyle factors, including obesity, physical inactivity, nutrition habits and alcohol consumption. In Europe, the probability of a woman developing breast cancer over her lifetime is approximately 1 in 8. An individual’s risk of breast cancer may be higher or lower than the average in view of the factors mentioned above. 15–40% of breast cancer cases may be prevented by lifestyle changes: weight control, exercise and reduced alcohol intake.

Breast cancer prevention and early detection

Most European countries have adopted breast cancer screening programmes for early disease detection. WHO recommends age-based screening for all women in EU countries aged between 50 and 69. In women over 50 years old, a well-organised, mammography-based programme with good compliance can reduce breast cancer mortality by at least 20%. However, current mammography screening systems have been associated with a number of highly debated limitations. In large part, their recommendations are based only on age. More precise patient selection methods could increase screening efficacy by detecting a larger number of cases from fewer patients.

Only about 10% of women with a family history of breast cancer have one of the deleterious single-gene mutations associated with the disease. Therefore, a risk prediction method that includes a polygenic component can assess the risks of the remaining 90% by combining genetics, family history and lifestyle factors.

Breast cancer risk can be explained, in part, using genetics. The breast cancer polygenic risk score (PRS), a major component in AnteBC, discriminates between different genetic risk levels and provides a more personalised approach to risk-stratified screening.

AnteBC will be available in the second half of 2019.