Radiotherapy in combination with immune checkpoint inhibitors.

PURPOSE OF REVIEW: The immunomodulatory effects of ionizing radiation have long been recognized; however, so far these have not been fully exploited in clinical practice. We review the rationale to combine radiation with immune checkpoint inhibitors, which are used in standard practice.

RECENT FINDINGS: Preclinical research suggests a synergy between radiotherapy and these immune checkpoint inhibitors. Whether or not this benefit translates into a clinical benefit is currently subject of ongoing research.

SUMMARY: It is highly rational to combine radiation with immune therapy as in preclinical models and in proof of concept trials in humans it clearly can increase the antitumor immunity when given together with other immune interventions.