Combined Radiation Therapy and Immune Checkpoint Blockade Therapy for Breast Cancer

Journal Article · Fri Sep 01 04:00:00 EDT 2017 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2017.05.029· OSTI ID:22723010

Ho, Alice Y. ^[1]; McArthur, Heather L. ^[2]

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1. Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States)
2. Breast Oncology Program, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California (United States)

Purpose: Treatment with checkpoint inhibitors has shown durable responses in a number of solid tumors, including melanoma, lung, and renal cell carcinoma. However, most breast cancers are resistant to monotherapy with checkpoint inhibitors. Radiation therapy (RT) has been shown to have a number of immunostimulatory effects, including priming the immune system, recruiting immune cells to the tumor environment, and altering the immunosuppressive effects of the tumor microenvironment. RT therefore represents a promising adjuvant therapy to checkpoint blockade in breast cancer. Methods and Materials: We review the data from the checkpoint blockade studies on breast cancer reported to date, the mechanisms by which RT potentiates immune responses, the preclinical and clinical data of checkpoint blockade and RT combinations, and the landscape of current clinical trials of RT and immune checkpoint inhibitor combinations in breast cancer. Results: Clinical trials with checkpoint blockade therapy have demonstrated response rates of up to 19% in breast cancer, and many of the responses are durable. Preclinical data indicate that RT combined with checkpoint inhibition synergizes not only to enhance antitumor efficacy but also to induce responses outside of the radiation field. Thus multiple clinical trials are currently investigating the combination of checkpoint inhibition with RT. Conclusions: The use of combination strategies that incorporate chemotherapy and/or local strategies such as RT may be needed to augment responses to immune therapy in breast cancer. Preclinical and clinical results show that RT in combination with checkpoint blockade may be a promising therapeutic option in breast cancer.

• OSTI ID: 22723010
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 1 Vol. 99; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
CHEMOTHERAPY
CLINICAL TRIALS
MAMMARY GLANDS
RADIOTHERAPY