HER2 Negative Breast Cancer

With this technology, we developed trastuzumab deruxtecan, the first DXd-ADC directed toward HER2. Additionally, Dato-DXd showed TROP2-dependent antitumor activity in multiple human cancer cell line-derived and patient-derived xenograft mouse models. Clinically, the global phase III trial targeting hormone receptor-positive, HER2-negative, unresectable or recurrent breast cancer led to its first approval in Japan in December 2024, followed by the approvals in the US and Europe later.

Present findings are from a small sample cohort and need further validation from a larger cohort. The online version contains supplementary material available at 10.1007/s13193-025-02427-0.

Rhabdomyolysis due to CDK4/6 inhibitor-statin interactions is a rare but potentially life-threatening complication. Vigilant monitoring, timely intervention, and tailored treatment strategies are essential for preventing complications and improving patient outcomes.

Disparities between Argentina's health subsystems significantly affect the BC stage at diagnosis and treatment timelines, influencing therapeutic pathways and associated costs. These findings highlight the need for targeted, system-level interventions. While further research is needed to confirm their long-term impact, such efforts may contribute to more equitable care and improved outcomes in LMICs.

In the context of contemporary adjuvant treatment, with patients diagnosed within three years postpartum more likely to receive chemotherapy, ovarian function suppression, and CDK4/6 inhibitors, differences in IDFS associated with time since last childbirth did not result in significantly worse IDFS within the follow-up period (89.0% in patients with PPBC up to 3 years vs. 93.7% in all other patients p = 0.39). These findings indicate that tumors diagnosed within the first year postpartum have significantly elevated RS, and that the period of most aggressive PPBC, as reflected by gene expression profiles, may arise in the more recently postpartum period, in the first 0-3 years postpartum.

P4, N=10, Recruiting, City of Hope Medical Center | Trial completion date: May 2026 --> Apr 2027 | Trial primary completion date: May 2026 --> Apr 2027

P1, N=330, Recruiting, Pyxis Oncology, Inc | Trial completion date: May 2027 --> Jun 2028 | Trial primary completion date: Jul 2026 --> Apr 2027

Culturally sensitive efforts are needed to promote awareness and increase breast cancer screening in distinct ethnic groups. The rapid recent increases in breast cancer incidence in Asian American, Native Hawaiian, and Pacific Islander women, especially early-onset disease, warrant urgent attention.

Younger patients with breast cancer exhibited a higher frequency of high-grade tumors, although no differences were observed in RFS and DRFS. However, locoregional recurrence was more common among younger patients, especially HR-positive/HER2-negative breast cancer.

This case highlights a rare but severe complication of ABE treatment. While CDK4/6 inhibitors are widely used as first-line agents in advanced breast cancer due to their high efficacy and generally favorable side-effect profile, clinicians should remain vigilant for NE, which requires prompt intervention.

P2, N=48, Active, not recruiting, City of Hope Medical Center | Trial completion date: Jun 2026 --> May 2027 | Trial primary completion date: Jun 2026 --> May 2027

We discuss the case literature on the management of ophthalmic and eyelid metastases, including the role of radiotherapy. We outline the multi-disciplinary team (MDT) discussions and recommendations made in the present case, which ultimately found that the risks of radiation toxicity would outweigh the benefits. Adjuvant therapy with fulvestrant and palbociclib was recommended, with future consideration of a CDK 4/6 inhibitor in the event of metastatic recurrence.