Clinical pilot for personalized risk-based breast cancer sceening

We will investigate whether women with an increased breast cancer risk will benefit from more personalized mammographic screening. In Norway, all women aged 50-69 are offered mammographic screening every second year. Women with an increased genetic risk might benefit from more frequent screning, and/or start screening at an earlier age. We will include women aged 40-49 with either low or high mammographic denisty, and offer a genetic test investigating their polygenetic risk score for breast cancer. A polygenetic risk score is a combined risk score including alterations in a large number of genes, that individully are not affecting breast cancer risk but that combined might increase the risk. If the genetic test does not show an increased risk, the woman will be offered standard mammographic screening. If an increased risk is detected, the woman will be offered a more personalized mammographic screening. THe women will be followed for 10 years.

The primary objective of the study is to evaluate the impact of implementing population-based genetic testing strategy for breast cancer precision prevention using the polygenic risk score and monogenic pathogenic variant (MPV) testing the Norwegian health care setting. 

Women aged 40-49 referred for clinical mammography with mammographic density BI-RADS a or d will be invited to participate in this prospective study. The included women will be offered genetic testing assessing their polygenic risk score (PRS) for breast cancer, and will be offered a personalized mammographic screening regime. Women with average or slightly elevated risk for breast cancer will be recommended standard mammography screening i BreastScreen Norway, whereas women with increased risk may be offered a personalized screening regime that may include more frequent screening or starting screening at an earlier age. We will collect data on family cancer history, and the women  will be offered genetic counselling/testing if indicated. We will follow the women for 10 years.

Inclusion criteria:  Women aged 40-49, referred for clincial mammography in Vestre Viken, with mammographic density BI-RADS a or b. 

Exclusion criteria: Prior history of malignant/premalignant breats disease. Alreadiy known familiar genetic predisposition for breast cancer.

PRS testing: Genotyping is performed using the AnteBC test (Antegenes, Estonia) with a non-invasive saliva-based method to collect and isolat a patient's DNA. 

Recommendation for mammpographic screening will be given based on the PRS-score. 

We will also collect patient information on life-style and medical history, as well as family history of cancer. Women considered having an increased familiar breast cancer risk based on family history will be offered genetic testing/counselling.