Enhancing the efficacy of immunotherapy using radiotherapy

Area of Science:

• Oncology
• Immunology
• Radiotherapy

Background:

• Cancer immunotherapy, particularly immune checkpoint blockade (ICB), has revolutionized cancer treatment.
• However, many patients do not respond to ICB, necessitating combination strategies.
• Radiotherapy is being investigated as a potent enhancer of ICB efficacy.

Purpose of the Study:

• To review the mechanisms by which radiotherapy augments antitumor immune responses.
• To discuss preclinical and clinical evidence for combining radiotherapy with ICB.
• To explore future directions, including optimal scheduling, biomarkers, and clinical translation.

Main Methods:

• Review of existing preclinical studies and clinical trials.
• Analysis of the immunological effects of radiotherapy.
• Discussion of therapeutic scheduling and predictive biomarkers.

Main Results:

• Radiotherapy induces DNA damage, apoptosis, and immunogenic cell death.
• Radiation alters immune cell populations within the tumor microenvironment, promoting an antitumor response.
• Emerging data from thoracic and other cancer trials suggest synergy between radiotherapy and ICB.

Conclusions:

• Radiotherapy can enhance the efficacy of immune checkpoint blockade by modulating the tumor immune microenvironment.
• Optimizing the combination of radiotherapy and ICB requires careful consideration of scheduling and predictive biomarkers.
• Further clinical translation holds significant promise for improving cancer patient outcomes.