Abstract PS3-01-19: Supplemental Imaging Improves Breast Cancer Early Detection but Remains Underutilized among High-Risk Women

Abstract Background: The MERIT (Mammography, Early Detection, Risk Assessment, and Imaging Technologies) cohort was established in 2017 at MD Anderson to integrate clinical, imaging, and blood biomarker data for personalized risk assessment of breast and other cancers. This analysis evaluates breast cancer detection rates and staging outcomes among women undergoing annual screening mammography with or without supplemental imaging. Methods: Between 2017 and the present, 8,099 women receiving annual screening mammograms were enrolled in the MERIT cohort. Participants were categorized based on imaging modality: mammography (MG) alone or MG with supplemental imaging, defined as receipt of breast MRI or CEM within two years of enrollment. Clinical data, imaging outcomes, and cancer diagnoses were collected. Follow-up time was calculated from enrollment to the date of the last breast imaging exam or breast cancer diagnosis. Cancers were classified as ductal carcinoma in situ (DCIS) or invasive, with staging and receptor subtype data collected when available. Results: Over 28,153 person-years of follow-up, 236 breast cancers were diagnosed. Women with cancer had a mean follow-up time of 2.30 years (SD = 1.86), compared to 3.51 years (SD = 2.19) among women without cancer. Among 1,505 women who underwent supplemental imaging, 61 breast cancers were identified, resulting in an incidence rate of 1,046 per 100,000 person-years. In this group, 38 percent of cancers were DCIS and 62 percent were invasive. No stage III or IV cancers were detected among women who received supplemental imaging.In contrast, among 6,594 women who received screening mammography alone, 175 breast cancers were diagnosed, yielding an incidence rate of 784 per 100,000 person-years. In this group, 28 percent of cancers were DCIS and 72 percent were invasive. Eleven late-stage cancers were identified in the mammography-alone group, including five stage IIB, three stage IIIB, one stage IIIC, and two stage IV cancers. Notably, eight of these were triple-negative, and two stage IV cases were hormone receptor-positive.MRI utilization varied by both breast density and Gail model risk classification. Among high-risk women with dense breasts, 37 percent received MRI, compared to 19 percent of high-risk women with non-dense breasts. Among low-risk women, MRI use was 16 percent for those with dense breasts and 9 percent for those with non-dense breasts. Conclusions: Supplemental imaging was associated with a higher breast cancer detection rate and a greater proportion of early-stage disease compared to mammography alone. The absence of late-stage cancers in the supplemental imaging group, in contrast to 11 advanced-stage cases in the MG-alone group, suggests a potential benefit for earlier detection through supplemental imaging. However, supplemental MRI remains underutilized among high-risk women. These findings support the need for personalized, risk-aligned screening strategies that integrate both breast density and formal risk assessment to improve early detection of clinically significant breast cancer. Citation Format: M. Imran, N. M. Kettner, S. Hanash, O. Weaver, J. Leung, J. Dennison. Supplemental Imaging Improves Breast Cancer Early Detection but Remains Underutilized among High-Risk Women abstract. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS3-01-19.