Abstract P2-02-04: Feasibility of breast cancer risk assessment during check-up in the general population for personalized screening and prevention recommendations: Preliminary results from a dedicated risk clinic

Abstract

Abstract Background: For women without specific high-risk, current breast cancer screening recommendations are based on age only, although the risk of developing cancer varies among women. While mammography screening reduces death from breast cancer, personalized screening strategies based on individual risk should improve the efficiency of screening programs and reduce overdiagnosis. However, data is limited on the feasibility of risk assessment in the general population of women undergoing routine screening mammography. Patients and Methods: Women, aged 35 or older and not previously identified as high risk, who scheduled an appointment at the Women's Risk Institute at the American Hospital of Paris underwent a complete breast cancer assessment including a questionnaire on personal and family history, mammogram with evaluation of breast density, collection of saliva sample, and consultation with a radiologist. DNA was extracted from saliva samples for genotyping of 76 single nucleotide polymorphisms (SNPs) using TaqMan® SNP Genotyping Assay. The polygenic risk score (PRS) was calculated using published per-allele odds ratio corresponding to the SNP associations with breast cancer. Breast density was estimated using a software tool, DenSeeMammo®. Women with 0 or 1 first-degree relative with breast cancer, diagnosed after the age of 40, were eligible for risk assessment using MammoRisk®, based on patient data, breast density, with or without PRS. For those with a strong family history of breast cancer, other risk assessment tools (Tyrer-Cuzick, Boadicea) were used. The visit concluded with a consultation with a breast cancer specialist to discuss the personalized screening and prevention plan based on the individual 5-year estimated risk. We compared the risk category assigned to each woman using MammoRisk® with and without PRS and analyzed whether the use of PRS modified clinical recommendations. Results: A total of 43 women underwent a breast cancer assessment between January and June 2019, with a median age of 52 (36-69). The entire assessment lasted approximately 2 hours including mammography exams. Thirty-two (74%) were eligible for MammoRisk® assessment: 13 (41%) were found to have moderate risk (5-year risk ≤1%), 13 (41%) intermediate risk (between 1 and 1.67%), and 6 (19%) high risk (≥1.67%). When using MammoRisk® with PRS, 14 (44%) were found to have moderate risk, 10 (31%) intermediate risk, and 8 (25%) high risk. The use of PRS changed the risk category for 14 women (44%): from moderate to intermediate (n=3), from intermediate to high (n=3), from moderate to high (n=1), from intermediate to moderate (n=5) and from high to intermediate (n=2). The use of PRS identified 3 (9%) women with a 5-year risk of ≥3%, who would be eligible for chemoprevention using Tamoxifen in the US. Results will be updated at presentation with data from over 100 patients. Conclusions: Breast cancer risk assessment is feasible in the general population. Risk assessment during check-up enabled the clinician to propose surveillance and shorter screening intervals to women at higher-than-average risk, and longer screening intervals to women at or below average risk. The use of PRS changed the risk score and the recommendations on monitoring and prevention in a subset of women. Results of ongoing large-scale studies will inform on the benefits of personalized screening strategies compared to the current age-based screening strategies for implementation by public health authorities in generalized breast cancer screening programs (Wisdom [NCT02620852], MyPEBS [NCT03672331]). <!–EndFragment→ Citation Format: Mahasti Saghatchian, Marc Abehsera, Marie-Laure Bara, Fabienne Lallouet, Tara Razani, Robert Sigal, Emilien Gauthier, Valerie Helin, David Gentien, Dominique Stoppa-Lyonnet. Feasibility of breast cancer risk assessment during check-up in the general population for personalized screening and prevention recommendations: Preliminary results from a dedicated risk clinic [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-02-04.