Assessing individual breast cancer risk within the UK National Health Service Breast Screening Programme: a new paradigm for cancer prevention.

Evans DG, Warwick J, Astley SM, Stavrinos P, Sahin S, Ingham SL, McBurney H, Eckersley B, Harvie M, Wilson M, Beetles UM, Warren RM, Hufton A, Sergeant J, Newman WG, Buchan I, Cuzick J, Howell A.

Source

1School of Medicine, University of Manchester.

Abstract

The aim of this study is to determine breast cancer risk at mammographic screening episodes and integrate standard risk factors with mammographic density and genetic data to assess changing the screening interval based on risk and offer women at high risk preventive strategies. We report our experience of assessing breast cancer risk within the UK NHS Breast Screening Programme using results from the first 10,000 women entered into the Predicting Risk Of breast Cancer At Screening (PROCAS) study. Of the first 28,849 women attending for screening at fifteen sites in Manchester 10,000 (35%) consented to study entry and completed the questionnaire. The median 10-year Tyrer-Cuzick breast cancer risk was 2.65%(IQR range 2.10-3.45). 107 women(1.07%) had 10-year risks ≥8% (high breast cancer risk) with a further 8.20% having moderately increased risk (5-8%). Mammographic density (percent dense area) was ≥60% in 8.3% of women. We collected saliva samples from 478 women for genetic analysis and will extend this to 18% of participants. At time of consent to the study, 95.0% of women indicated they wished to know their risk. Women with a 10-year risk of ≥8% or 5-8% and mammographic density of ≥60% were invited to attend or be telephoned to receive risk counselling; 81.9% of those wishing to know their risk have received risk counselling and 85.7% of these were found to be eligible for a risk reducing intervention. These results confirm the feasibility of determining breast cancer risk and acting on the information in the context of population-based mammographic screening.