Abstract P6-03-01: The MERIT Cohort: An MD Anderson Initiative to Integrate Blood and Imaging Biomarkers to Personalize Breast Cancer Risk

Abstract Background: The MERIT cohort (Mammography, Early Detection, Risk Assessment, and Imaging Technologies, 2017-present) has enrolled women receiving annual screening mammograms (MG) at MD Anderson with a primary goal to integrate clinical data and imaging data with blood biomarker profiles to determine risk of developing breast and other cancers. Here we report interim results for breast cancers among post-menopausal women in the cohort categorized based on breast density and BMI and differences between participants who underwent MRI/MG screening vs standard annual MG screening. Methods: The study annually collects comprehensive health measurements, questionnaire information, imaging data, and blood specimens. Plasma is processed and frozen within 4 hours of collection (draw-to-freezer, >500,000 aliquots to date) for biomarker research. Part of the cohort also has MRI screening every 6 months alternating with standard mammography (MRI/MG). BI-RADS breast density was determined by radiologist scoring using the baseline mammogram. Self-reported post-menopausal status (12 months without a menstrual period) was used to classify participants. When not available, those participants older than 50 years were classified as post-menopausal. Results: 4,392 of the 6,222 eligible subjects from MERIT were post-menopausal and included in the analyses. The average follow up was 2.4 mammograms per participant. MRI/MG screening was used for 385 (8.8%) participants who were more likely to be younger (59.6 vs 62.1 years, P< 0.01), have lower BMI (27.9 vs 28.6, P = 0.02) and dense breasts (64% vs 50%, P< 0.01). The rates of breast cancer were overall higher for those screened by MRI/MG vs standard MG (13.9 vs 6.9 cases per 1,000 mammograms). A total of 79 breast cancers (7.6 cases per 1,000 mammograms) were diagnosed with the highest rate of breast cancers in high BMI participants with dense breasts (see table). A blood-based biomarker profile for risk of breast cancer with high BMI was developed using matched pre-diagnostic plasma by mass spectrometry metabolomic analyses. Conclusions: The MERIT cohort has a higher-than-average rate of breast cancers, in part explained by a high-risk MRI/MG screening group. High BMI and dense breasts were generally associated with higher rates of breast cancer. The differences in the rates of breast cancer incidence for the high BMI group between non dense and dense breasts is likely understated for the standard mammogram group because of the lower sensitivity of mammography in dense breasts. Interestingly, the rates of breast cancers in the low BMI/non dense breast group were almost equally high as the low BMI/dense breast group, likely a result of reduced sensitivity of mammography for dense breasts. For future work, we will integrate the blood biomarker profiles with the breast density and BMI information to develop a more personalized risk model. MERIT Cohort Breast Cancers Rates of diagnosed breast cancers per 1,000 mammograms for post-menopausal women (N = 79 breast cancers)*‡P<0.01, †P<0.05, Fisher’s exact test Citation Format: Jessica Leung, Olena Weaver, Samir Hanash, Jennifer Dennison. The MERIT Cohort: An MD Anderson Initiative to Integrate Blood and Imaging Biomarkers to Personalize Breast Cancer Risk [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-03-01.