P4-11-07: Feasibility and Acceptability of Offering Breast Cancer Risk Estimation in the Context of the UK National Health Service Breast Cancer Screening Programme: A New Paradigm for Cancer Prevention

Background: Currently there are no real attempts internationally to tailor breast screening programmes to individual risk Methods: We have assessed the feasibility of collecting breast cancer risk information during routine mammographic screening in the National Health Service Breast Screening Programme (NHSBSP) in England, in order to consider, ultimately, adapting the screening interval to risk of breast cancer and introducing preventive strategies in women at high risk. The study Predicting Risk Of Cancer At Screening (PROCAS) aims to recruit 60,000 women over 3 years. Results: 26,000 women (June 8th 2011) have so far given consent to join the study. Thirty six percent of the first 20,000 women in nineteen screening sites in Manchester consented to enter the study and completed a risk factor questionnaire. The median 10 year breast cancer risk was 2.65%, with 926 (9.26%) of the first 10,000 women having a 10 year risk of ≥5% and 92 (0.92%) having a 10 year risk of ≥8% (Tyrer-Cuzick), IQR:1.35. 832 (8.32%) women had a mammographic density of 60% or greater (Visual Analogue Scale). We collected saliva samples from 1019 women for genetic analysis and will extend this to 18% of participants. Of those who agreed to participate in the study, 94% indicated that they wished to know their breast cancer risk. Women with a 10-year risk of ≥8%, and women with a 10-year risk of ≥5% and mammographic density ≥60% were invited to attend or be telephoned to be counselled. To date 138 have accepted with 135, so far, having received risk counselling. Nineteen percent of the high-risk women identified subsequently decided to enter a randomised breast cancer prevention study with either a dietary or drug intervention (IBIS2, anastrazole vs placebo). Results from the first 1,000 women who provided DNA samples suggest that the risk information from the 18 validated SNPS may enhance existing risk models. Conclusion: This study demonstrates that it is feasible to determine individual breast cancer risk and offer women appropriate risk-reducing interventions within the context of a population-based mammographic screening programme. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-11-07.