Abstract PS5-12-10: Impact of KEYNOTE-522 on BneoCT: An Institutional Quality Measure Improvement Analysis

Abstract Background: Early stage HER2-positive breast cancer (HER2+) and triple-negative breast cancer (TNBC) are associated with a high recurrence risk. In 2022, BneoCT was formally introduced as a Commission on Cancer (CoC) breast quality measure. The metric focuses on the timely initiation of neoadjuvant therapy in eligible patients. More specifically, BneoCT is a measure of patients 75 years of age or younger, with early stage HER2-positive breast cancer or TNBC, for whom neoadjuvant chemotherapy, targeted therapy, and/or immunotherapy is initiated within 60 days of diagnosis. Methods: We evaluated annual BneoCT performance rates from 2021 to June 2025 at 4 Icahn School of Medicine/Mount Sinai campuses: Mount Sinai Downtown, Mount Sinai Brooklyn, Mount Sinai West, and Mount Sinai Morningside, as reported in institutional quality dashboards. The benchmark for BneoCT is 95%. Results: At our institutions, performance on the BneoCT measure improved steadily over 4 consecutive years (Table 1). This upward trend reflects a 6.25% absolute increase from 2021 to 2024, and a 10.31% absolute increase from 2021 to 30th June 2025. While multiple factors likely contributed, we believe that results from the KEYNOTE-522 trial, which demonstrated that the addition of pembrolizumab to neoadjuvant chemotherapy in high-risk early-stage TNBC significantly improved pathologic complete response (pCR) rates and event-free survival, followed by the National Comprehensive Cancer Network’s (NCCN) endorsement of KEYNOTE-522 in May 2021 (NCCN Version 4.2021), was a critical driver for earlier multidisciplinary coordination and greater utilization of neoadjuvant therapy pathways. The inclusion of pembrolizumab in NCCN Version 4.2021 marked a pivotal shift in practice standards for TNBC, prompting widespread institutional adoption of this immunotherapy-based neoadjuvant regimen. This facilitated earlier referrals and systemic therapy initiation, directly improving adherence to the BneoCT benchmark. Although HER2+ breast cancer cases were not directly affected by KEYNOTE-522, the broader trend toward aggressive, guideline-aligned neoadjuvant therapy likely enhanced care timeliness across both TNBC and HER2+ populations included in BneoCT. Conclusion: The integration of KEYNOTE-522 into the NCCN Guidelines in May 2021 played a substantial role in driving improvements in the BneoCT quality measure over the subsequent years. This quality measure improvement analysis illustrates how high-impact clinical trial data, when rapidly translated into national guidelines, can meaningfully influence patient care outcomes and institutional quality metrics. Sustained performance improvement at or above benchmark levels will require continued investment in multidisciplinary coordination, treatment pathway optimization, and early diagnosis-to-therapy transitions. Citation Format: K. Rupani, C. Williams, P. Klein. Impact of KEYNOTE-522 on BneoCT: An Institutional Quality Measure Improvement Analysis [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 PS5-12-10.