Knowledge mapping and research trends of chimeric antigen receptor T-cell immunotherapy in breast cancer: A bibliometric and visual analytics study

Chimeric antigen receptor T cell (CAR-T) immunotherapy has achieved landmark success in hematologic malignancies and is being explored for breast cancer (BC) and other solid tumors, prompting research to improve efficacy and safety. We retrieved 894 related to CAR-T immunotherapy for BC from the Web of Science Core Collection and performed bibliometric analyses using CiteSpace and VOSviewer to map the research landscape, development trajectory, and key contributors. Joinpoint regression assessed temporal trends in annual publications using R 4.4.2. The USA led publication output. Institutional co-occurrence revealed the University of London and Technische Universität Dresden as central hubs. CANCER RES and FRONT IMMUNOL were identified as core journals. Darcy PK and Morgan RA were prominent authors by output and citations. Keyword clustering and timeline visualization indicated that the terms "in vivo," "tumor microenvironment (TME)," and "targeted therapy" have remained highly active in recent years. In addition, burst detection analysis revealed that keywords including TME, "epithelial-mesenchymal transition," and "mesothelin" have gradually emerged as research frontiers, suggesting increasing attention to resistance mechanisms and tumor immune regulation. These findings provide a systematic overview of the evolving research landscape and help identify emerging hotspots and future directions. BC remains the most frequently diagnosed malignancy among women worldwide and a major cause of cancer-related death. We systematically mapped the knowledge structure and development trends of CAR-T research in BC, identifying major research contributors and emerging research hotspots, which may provide valuable insights for future basic research and clinical exploration in this field.