ENAR
Systemic drug therapies for metastatic breast cancer (adapted from Reference 1)
For women with stage IV breast cancer, systemic therapies or combination of these are the main treatments.

Hormone therapy
CLICK TO KNOW MORE

Targeted therapy
CLICK TO KNOW MORE

Chemotherapy
CLICK TO KNOW MORE

Immunotherapy
CLICK TO KNOW MORE

Radiation therapy
(in certain situations)

Surgery
(in certain situations)

Treatment can often shrink tumors (or slow their growth), improve symptoms, and help women live longer. These cancers are considered incurable.2
“What to Ask Your Doctor” Guide
Hormone therapy
Hormone therapy is usually the first treatment for hormone receptor-positive metastatic breast cancers. Hormone therapy drugs work by preventing the cancer cells from getting the estrogen they need to grow. For women, the choice of hormone therapy depends on menopausal status and any past hormone treatment for early breast cancer.
Some hormone therapy drugs (like tamoxifen and aromatase inhibitors) are pills. Others (like goserelin or fulvestrant) are given by injection.
At some point, even though it may be years away, hormone therapy almost always stops working. At this point, chemotherapy may be recommended.3
CDK (Cyclin Dependent Kinase) 4/6 inhibitors in metastatic breast cancer
CDK4 and CDK6 are enzymes important in cell division. CDK4/6 inhibitors are a class of drugs designed to interrupt the growth of cancer cells.3
Certain cancers, for example, hormone receptor-positive breast cancer, are more likely to have disturbances in CDK4/6, and CDK 4/6 inhibitors may form part of the treatment protocol.4 Most often, CDK4/6 inhibitors are given in combination with hormonal therapy (such as an aromatase inhibitor or fulvestrant).5
Research suggests CDK4/6 inhibitors may increase the time people have before cancer spreads and also help them live longer.3

Reference:

  1. Life With Metastatic Breast Cancer. WebMD [uploaded 2020 Jan 28; cited 2020 Jun 05]. Available from: https://www.webmd.com/breast-cancer/treatments-metastatic-breast-cancer#1. Accessed on September 2021.
  2. Treatment of Stage IV (Metastatic) Breast Cancer. American Cancer Society [updated 2020 Apr 21; cited 2020 Jun 05]. Available from:https://www.cancer.org/cancer/breast-cancer/treatment/treatment-of-breast-cancer-by-stage/treatment-of-stage-iv-advanced-breast-cancer.html. Accessed on September 2021.
  3. Treatments for Metastatic Breast Cancer. Susan G. Komen [updated 2020 May 18; cited 2020 Jun 05]. Available from: https://ww5.komen.org/BreastCancer/RecommendedTreatmentsfor
    MetastaticBreastCancer.html    . Accessed on September 2021.
  4. Preusser, M., De Mattos-Arruda, L., Thill, M., Criscitiello, C., Bartsch, R., Ruhstaller, T., de Azambuja, E., & Zielinski, C. C. (2018). CDK4/6 inhibitors in the treatment of patients with breast cancer: summary of a multidisciplinary \ round-table discussion. ESMO open, 3(5), e000368. https://doi.org/10.1136/esmoopen-2018-000368
  5. Spring LM, Wander SA, Zangardi M, Bardia A. CDK 4/6 Inhibitors in Breast Cancer: Current Controversies and Future Directions. Curr Oncol Rep. 2019;21(3):25. Published 2019 Feb 26.
BACK
Targeted therapies
Targeted therapies are treatments that target specific characteristics of cancer cells, such as a protein that allows the cancer cells to grow in a rapid or abnormal way. Targeted therapies are generally less likely than chemotherapy to harm normal, healthy cells.4
i. Drugs used in combination with hormone therapy
CDK4/6 inhibitors, mTOR inhibitors and PI3 kinase inhibitors are types of drugs used in combination with hormone therapy to treat some metastatic breast cancers.3
ii. Anti-HER2 therapies
Some breast cancer cells have high proportion of a protein called HER2 (human epidermal growth factor receptor type 2), which makes them more likely to grow and spread. Drugs that target this protein can help slow the growth of HER2-positive breast cancers.1
CDK (Cyclin Dependent Kinase) 4/6 inhibitors in metastatic breast cancer
CDK4 and CDK6 are enzymes important in cell division. CDK4/6 inhibitors are a class of drugs designed to interrupt the growth of cancer cells.4
Certain cancers, for example, hormone receptor-positive breast cancer, are more likely to have disturbances in CDK4/6, and CDK 4/6 inhibitors may form part of the treatment protocol.5 Most often, CDK4/6 inhibitors are given in combination with hormonal therapy (such as an aromatase inhibitor or fulvestrant).6
Research suggests CDK4/6 inhibitors may increase the time people have before cancer spreads and also help them live longer.3

Reference:

  1. Life With Metastatic Breast Cancer. WebMD [uploaded 2020 Jan 28; cited 2020 Jun 05]. Available from https://www.webmd.com/breast-cancer/treatments-metastatic-breast-cancer#1. Accessed on September 2021.
  2. Treatment of Stage IV (Metastatic) Breast Cancer. American Cancer Society [updated 2020 Apr 21; cited 2020 Jun 05].
    Available from: https://www.cancer.org/cancer/breast-cancer/treatment/treatment-of-breast-cancer-by-stage/treatment-of-stage-iv-advanced-breast-cancer.html. Accessed on September 2021.
  3. Treatments for Metastatic Breast Cancer. Susan G. Komen [updated 2020 May 18; cited 2020 Jun 05]. Available from: https://ww5.komen.org/BreastCancer/Recommended
    TreatmentsforMetastaticBreastCancer.html    . Accessed on September 2021.
  4. Targeted Therapies to Treat Metastatic Breast Cancer. BreastCancer.Org [updated 2020 Jan 22; Cited 2020 Jun 05].
    Available from: https://www.breastcancer.org/symptoms/types/recur_metast/
    treat_metast/options/targeted    . Accessed on September 2021.
  5. Preusser, M., De Mattos-Arruda, L., Thill, M., Criscitiello, C., Bartsch, R., Ruhstaller, T., de Azambuja, E., & Zielinski, C. C. (2018). CDK4/6 inhibitors in the treatment of patients with breast cancer: summary of a multidisciplinary \ round-table discussion. ESMO open, 3(5), e000368. https://doi.org/10.1136/esmoopen-2018-000368
  6. Spring LM, Wander SA, Zangardi M, Bardia A. CDK 4/6 Inhibitors in Breast Cancer: Current Controversies and Future Directions. Curr Oncol Rep. 2019;21(3):25. Published 2019 Feb 26.
BACK
Chemotherapy
Chemotherapy is used to treat metastatic breast cancer by destroying or damaging the cancer cells as much as possible. Chemotherapy is often used in combination within its group or with targeted therapies. Chemotherapy is usually reserved for use later in the treatment sequence for cancers that are hormone sensitive.3

Reference:

  1. Life With Metastatic Breast Cancer. WebMD [uploaded 2020 Jan 28; cited 2020 Jun 05]. Available from: https://www.webmd.com/breast-cancer/treatments-metastatic-breast-cancer#1. Accessed on September 2021.
  2. Treatment of Stage IV (Metastatic) Breast Cancer. American Cancer Society [updated 2020 Apr 21; cited 2020 Jun 05]. Available from:https://www.cancer.org/cancer/breast-cancer/treatment/treatment-of-breast-cancer-by-stage/treatment-of-stage-iv-advanced-breast-cancer.html. Accessed on September 2021.
  3. Chemotherapy to Treat Metastatic Breast Cancer. BreastCancer.Org [updated 2019 Mar 23; cited 2020 Jun 05]. Available from: https://www.breastcancer.org/symptoms/types/recur_metast/
    treat_metast/options/che    . Accessed on September 2021.
BACK
Immunotherapy
Immunotherapy is the use of medicines to stimulate a  person’s own immune system to recognize and destroy cancer cells more effectively. Immunotherapy can be used to treat some types of breast cancer.3

Reference:

  1. Life With Metastatic Breast Cancer. WebMD [uploaded 2020 Jan 28; cited 2020 Jun 05]. Available from: https://www.webmd.com/breast-cancer/treatments-metastatic-breast-cancer#1. Accessed on September 2021.
  2. Treatment of Stage IV (Metastatic) Breast Cancer. American Cancer Society [updated 2020 Apr 21; cited 2020 Jun 05]. Available from:https://www.cancer.org/cancer/breast-cancer/treatment/treatment-of-breast-cancer-by-stage/treatment-of-stage-iv-advanced-breast-cancer.html. Accessed on September 2021.
  3. Immunotherapy for Breast Cancer. American Cancer Society [updated 2019 Sep 18; cited 2020 Jun 05]. Available from: https://www.cancer.org/cancer/breast-cancer/treatment/immunotherapy.html. Accessed on September 2021.
BACK