Endocrine Therapy for Breast Cancer

Published:November 29, 2020DOI:https://doi.org/10.1016/j.nurpra.2020.10.015


      • Endocrine therapy is commonly used to treat breast cancer.
      • The duration of endocrine therapy is usually at least 5 years.
      • Side effects relate to estrogen inhibition.
      • Knowledge about endocrine therapy is important for primary care providers.


      Endocrine therapy is the primary treatment for the most common types of breast cancer. Endocrine agents work by inhibiting the tumor-stimulating effects of estrogen in hormone-sensitive tumors. A new class of targeted drugs synergize with endocrine agents to improve survival for patients with metastatic disease. Endocrine therapy is continued for years, and long-term survival is common, although toxicities often occur due to the alteration of the physiologic effects of estrogen. It is important, therefore, that primary care providers remain knowledgeable about patient needs during and after treatment.


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      Jeanne F. Noe, PharmD, BCOP, is an independent consultant pharmacist, Chapel Hill, NC.


      Margaret A. Bush, PhD, BCOP, is an associate professor, Duke University School of Nursing, Durham, NC. She can be contacted at [email protected] .