Work

Breast Cancer Evaluation and Targeted Investigational Therapy (BEAT-IT): A Pilot Prospective Tissue-Testing Study for Breast Cancer Clinical Trial Enrollment

Year: 2026

Type: preprint

Abstract: Background Metastatic breast cancer (mBC) is heterogeneous not only clinically but genomically. Beyond 2–3 lines of therapy, many patients lack access to rationally selected investigational therapies. We evaluated whether a prospective, multi-omics assay from obtained tissue could 1) identify actionable alterations with rapid turnaround and 2) channel patients to biomarker-matched clinical trials, while maintaining procedural safety. Methods BEAT-IT was a prospective study in which core biopsies from patients with mBC (primary and metastatic lesions) were evaluated using immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and next-generation sequencing (NGS). Primary endpoint was the proportion of patients bearing actionable alterations and the proportion referred to biomarker-matched trials. Secondary endpoints included turnaround time (TAT) and biopsy-related morbidity. Proportions are reported with Wilson 95% confidence intervals (CIs). Exploratory subgroup comparisons including molecular subtype comparison were planned with chi-square or Fisher's exact tests. Results Among the 157 enrolled participants, the median TAT from biopsy to finalized report was 20 days. Actionable alterations were identified in 49.0% (77/157; 95% CI 41.3–56.8%). Overall, 49 of 157 patients (31.2%; 95% CI 24.5–38.8%) enrolled in at least one therapeutic clinical trial after profiling. A single grade 1 pneumothorax (1/162 biopsied patients, 0.6%) was the only biopsy-related complication. Retrospective annotation using current ESCAT criteria identified a tier I alteration in 20% of patients with tumor-informative DNA results. Conclusions Prospective, biopsy-triggered multi-omics profiling in mBC is feasible, safe, and delivers clinically actionable results within approximately 3 weeks. Our approach identified actionable alterations in approximately half of patients and supported enrollment in therapeutic clinical trials for nearly one-third. Trial registration: This study evaluated a diagnostic/implementation strategy without assignment to a therapeutic intervention; clinical-trial registration was not required.

Source: Research Square

DOI: 10.21203/rs.3.rs-10936036/v1