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Checkpoint blockade in the treatment of breast cancer: current status and future directions

British Journal of Cancer (2018) | Download Citation


There is now accumulating evidence that the host immune system plays an important role in influencing response to treatment and prognosis in breast cancer. Immunotherapy with immune checkpoint inhibitors is a promising and rapidly growing field of interest in many solid tumours, including breast cancer. Trials to date have largely focused on metastatic triple-negative disease, a genomically unstable subtype of breast cancer that is believed to be the most immunogenic and following the development of treatment resistance, has limited treatment options and a particularly poor prognosis. Both checkpoint inhibitor monotherapy and combinations with chemotherapy are being investigated. In this review, we discuss the current evidence for PD-1/PD-L1 blockade in metastatic triple-negative breast cancer (TNBC), HER2+ breast cancer and ER+ disease, as well as the emerging evidence for use in the early-stage (neoadjuvant) setting. We also propose potential ways of improving responses to checkpoint blockade in breast cancer.

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Author information


  1. Peter MacCallum Cancer Centre, Melbourne, VIC, Australia

    • Lironne Wein
    • , Stephen J Luen
    • , Peter Savas
    • , Roberto Salgado
    •  & Sherene Loi
  2. Department of Pathology/GZA, Antwerp, Belgium

    • Roberto Salgado
  3. University of Melbourne, Melbourne, VIC, Australia

    • Sherene Loi


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Preparation/drafting of the manuscript: L.W., S.J.L., P.S., R.S. and S.L. Figures: L.W. and S.L.

Competing interests

S.J.L. is supported by the University of Melbourne. S.L. is supported by the Cancer Council Victoria John Colebatch fellowship, the Breast Cancer Research Foundation (BCRF) NY, the National Health and Medical Research Council (NHMRC) of Australia. R.S. is supported by the BCRF.

Note: This work is published under the standard license to publish agreement. After 12 months the work will become freely available and the license terms will switch to a Creative Commons Attribution 4.0 International (CC BY 4.0).

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Correspondence to Sherene Loi.

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