Editor’s Note: In the treatment landscape of HR+/HER2- metastatic breast cancer (MBC), CDK4/6 inhibitors (CDK4/6i) combined with endocrine therapy (ET) have become a widely used first-line treatment. However, patients with symptomatic visceral metastases often opt for chemotherapy (CT). While some prospective studies suggest that CDK4/6i + ET may yield better outcomes even in patients with visceral metastases, no studies have explored these strategies in real-world settings.

To address this gap, Dr. Biyun Wang from Fudan University Shanghai Cancer Center spearheaded a multicenter real-world study, the YOUNGBC-30 trial, to retrospectively analyze data from six institutions between 2020 and 2023. The study compared the efficacy and safety of CDK4/6i + ET and CT in HR+/HER2- MBC patients, providing valuable real-world evidence to guide clinical decision-making. This research was accepted for presentation at the 2024 SABCS (Abstract No. P4-07-16).

Oncology Frontier: Dr. Wang, what were the key findings of the YOUNGBC-30 study, and how do they impact clinical practice?

Dr. Biyun Wang:This study generated significant discussion among experts at SABCS. Traditionally, it has been assumed that patients with rapidly progressing, high-burden tumors might respond better to chemotherapy. However, in the visceral crisis subgroup of this study, the efficacy of chemotherapy and CDK4/6i + ET was comparable.

Some experts noted that the lack of a statistical difference in this subgroup may be due to the limited sample size. Additionally, a few patients in the chemotherapy group, who responded exceptionally well, achieved progression-free survival (PFS) of over two years, significantly extending the PFS data for the chemotherapy group. This could explain why no significant differences were observed.

Future research on maintenance therapy strategies following chemotherapy is also eagerly anticipated to provide further guidance.

Dr. Biyun Wang

• Director, Breast and Genitourinary Oncology Department, Fudan University Shanghai Cancer Center
• Chief Physician and Master’s Supervisor
• Executive Member, Chinese Society of Clinical Oncology (CSCO)
• Chair, CSCO Youth Committee
• Secretary-General, CSCO Patient Education Expert Committee
• Member, CSCO Breast Cancer Expert Committee
• Chair, CRPC Committee, Shanghai Anti-Cancer Association
• Standing Committee Member, Breast Cancer Professional Committee, Shanghai Anti-Cancer Association

Dr. Yizhao Xie

• PhD in Oncology
• Resident Physician, Department of Oncology, Fudan University Shanghai Cancer Center
• Member, Youth Committee of the Shanghai Anti-Cancer Association for Cancer Rehabilitation and Palliative Care

Yifan Chen

• Master’s Student, Fudan University Shanghai Cancer Center
• Research Focus: Chemotherapy and Multimodal Treatment of Breast Cancer