Cancer Res Treat.  2023 Oct;55(4):1065-1076. 10.4143/crt.2023.846.

Recent Developments in the Therapeutic Landscape of Advanced or Metastatic Hormone Receptor–Positive Breast Cancer

• Lee EY
• Lee DW
• Lee KH
• Im SA

• KMID: 2547781
• DOI: http://doi.org/10.4143/crt.2023.846

Abstract

Hormone receptor–positive (HR+) disease is the most frequently diagnosed subtype of breast cancer. Among tumor subtypes, natural course of HR+ breast cancer is indolent with favorable prognosis compared to other subtypes such as human epidermal growth factor protein 2–positive disease and triple-negative disease. HR+ tumors are dependent on steroid hormone signaling and endocrine therapy is the main treatment option. Recently, the discovery of cyclin-dependent kinase 4/6 inhibitors and their synergistic effects with endocrine therapy has dramatically improved treatment outcome of advanced HR+ breast cancer. The demonstrated efficacy of additional nonhormonal agents, such as targeted therapy against mammalian target of rapamycin and phosphatidylinositol 3-kinase signaling, poly(ADP-ribose) polymerase inhibitors, antibody-drug conjugates, and immunotherapeutic agents have further expanded the available therapeutic options. This article reviews the latest advancements in the treatment of HR+ breast cancer, and in doing so discusses not only the development of currently available treatment regimens but also emerging therapies that invite future research opportunities in the field.

Keyword

Breast neoplasms; Endocrine therapy; Hormone receptor positive; CDK4/6 inhibitor

Figure

• 

  Fig. 1. Treatment of advanced/metastatic hormone receptor (HR)–positive, human epidermal growth factor protein 2 (HER2)–negative breast cancer. ESR1, estrogen receptor 1; ET, endocrine therapy; OFS, ovarian function suppression; PD, progressive disease; SERD, selective estrogen receptor degrader; T-Dxd, trastuzumab-deruxtecan; ULN, upper limit of normal.

Reference

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