Targeted and Chemo-Free Approaches in HER2-Positive Early Breast Cancer: A Systematic Review and Meta-Analysis

Area of Science:

• Oncology
• Clinical Research
• Pharmacology

Background:

• HER2-positive breast cancer presents aggressive growth and poor prognosis without treatment.
• Chemotherapy-free regimens are emerging as a strategy to improve outcomes in early HER2-positive breast cancer.
• Assessing the efficacy and safety of these novel regimens is crucial for treatment optimization.

Purpose of the Study:

• To evaluate the efficacy and safety of chemotherapy-free regimens in patients with HER2-positive early breast cancer.
• To compare treatment outcomes between chemotherapy-free and conventional chemotherapy regimens.
• To analyze pathologic complete response (pCR), invasive disease-free survival (iDFS), and event-free survival (EFS).

Main Methods:

• A systematic literature search was performed across major databases (PubMed, CENTRAL, Google Scholar, Embase) up to July 2024.
• Included five randomized trials involving 1489 patients with early-stage HER2-positive breast cancer.
• Meta-analysis was used to pool data on treatment efficacy and safety outcomes.

Main Results:

• Approximately 26.1% of patients on chemotherapy-free regimens achieved pCR.
• Chemotherapy-free regimens showed high 3-year and 5-year iDFS (95.40%, 85.71%) and 5-year EFS (81.13%).
• Discontinuation rates due to adverse events were similar between chemotherapy-free and conventional groups (OR: 0.29, P=0.18), but pCR was inferior compared to chemotherapy plus anti-HER2 drugs.

Conclusions:

• Chemotherapy-free regimens demonstrate encouraging efficacy and survival benefits for HER2-positive early breast cancer.
• Despite promising safety, chemotherapy combined with anti-HER2 drugs remains superior in achieving overall clinical outcomes.
• Further research may refine chemotherapy-free strategies for specific patient populations.