Cancer Res Treat.  2024 Jul;56(3):700-720. 10.4143/crt.2023.1138.

HER2-Low Breast Cancer: Now and in the Future

• Kang S
• Kim SB

• KMID: 2557659
• DOI: http://doi.org/10.4143/crt.2023.1138

Abstract

Breast cancer is a heterogeneous disease, and its subtypes are characterized by hormone receptor and human epidermal growth factor receptor 2 (HER2) expression status. “HER2-low” tumors, which exhibit a low level of HER2 expression (immunohistochemistry 1+ or 2+ without gene amplification), were conventionally considered not amenable to anti-HER2 targeting agents based on the results of a phase III trial of trastuzumab. However, this perspective is being challenged by the emergence of novel anti-HER2 antibody-drug conjugates, such as trastuzumab-deruxtecan. These innovative therapies have demonstrated remarkable efficacy against HER2-low breast cancer, shedding new light on a previously overlooked category of breast cancer. Such promising results highlight the need for in-depth investigations of the biology and prognostic implications of HER2-low tumors. In this review, we comprehensively summarize the current evidence surrounding this topic and highlight areas that warrant further exploration and research in the future.

Keyword

Breast neoplasms; HER2-low; DS-8201a

Reference

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