Hormone Receptor Positive Breast Cancer

P2, N=60, Recruiting, University of Texas Southwestern Medical Center | Trial primary completion date: Apr 2026 --> Apr 2027

P1/2, N=1132, Recruiting, Hoffmann-La Roche | N=792 --> 1132

P2, N=43, Active, not recruiting, Memorial Sloan Kettering Cancer Center | Trial completion date: Mar 2026 --> Mar 2027 | Trial primary completion date: Mar 2026 --> Mar 2027

HER2-low status was associated with worse OS in breast cancer patients with certain negative prognostic factors compared with HER2-zero status. Additionally, HER2-low1+ and HER2-low2+/ISH(-) subgroups predominantly exhibited HR+ status.

Antibody-drug conjugates (ADCs), such as trastuzumab deruxtecan (T-DXd) and sacituzumab govitecan (SG) offer new and potent options for curing for curing hormone receptor-positive (HR+)/human epidermal growth factor receptor 2 (HER2)-low advanced breast cancer; however, comparisons in terms of their relative effectiveness and safety concerns are lacking. Compared with other ADC drugs, T-DXd showed relatively better treatment characteristics, better PFS benefit, and relatively low incidence of serious AEs (SAEs). Combined with RCTs and real-world data, T-DXd has potential advantages in this population.

Utidelone plus capecitabine has brought therapeutic and survival benefits in the second-line treatment of patients with advanced breast cancer (ABC). Utidelone demonstrates favorable efficacy and safety in patients with refractory ABC, particularly in HR+/HER2- patients. The combination of utidelone with anti-angiogenic therapy shows promising intracranial anti-tumor activity and is expected to be a preferred option for ABC in subsequent lines of treatment.

We recommend a tiered approach of CAB testing in patients with MF/MC BC, whereby, if the first tumor shows CAB-low risk, testing of additional tumor foci is recommended. This approach improves risk stratification and enables tailored adjuvant treatment planning, while minimizing the risk of undertreatment.

Postoperatively, he received adjuvant stereotactic radiosurgery (30-35 Gy in five fractions) to the resection cavity and was transitioned from tamoxifen to trastuzumab deruxtecan (T-DXd) for improved CNS-directed systemic therapy. Surveillance imaging at 6 months demonstrated no intracranial recurrence, and systemic restaging showed no extracranial disease progression. This case highlights the importance of prompt neuroimaging for new neurological symptoms in male breast cancer patients and supports a multimodal strategy, including surgical resection, focal radiation, and CNS-penetrant HER2-targeted therapy, for achieving durable intracranial control in select patients with isolated brain metastasis.

We identified several factors associated with LR rates after mastectomy. Despite the observational character of our study, these factors could be considered in future treatment decision-making.

Baseline 18 F-FDG PET/CT may provide prognostic insights in HR+/HER2- metastatic breast cancer. High MTV and TLG are associated with poorer OS in univariate analyses but not in multivariable analyses. ECOG score > 0 and age ≥ 60 years are independent predictors of PFS.

These results demonstrate that both dPCR and NGS-based liquid biopsy workflows can be successfully implemented for ESR1 mutation testing in routine clinical practice using locally validated assays. This multicentre verification study provides practical guidance on assay verification, DNA input requirements, and key analytical parameters required to ensure reliable ESR1 mutation detection across different European laboratories. Robust analytical verification of ESR1 testing may improve diagnostic reliability and support personalized treatment strategies for patients with hormone receptor-positive, HER2-negative metastatic breast cancer.

Transcriptomic analysis in 19 patients indicates that high MuS is associated with immune activation and enrichment of cell-cycle and purine-metabolism pathways. The Mu-model provides non-invasive DFS prediction and recurrence risk stratification, while preliminarily exploring its potential to identify patients who may derive differential benefits from adjuvant therapy.