The Proimmunomodulatory and Anti-immunomodulatory Effects of Radiotherapy in Oncologic Care

The abscopal effect in radiotherapy (RT) refers to the phenomenon where localized radiation treatment causes regression of distant, nonirradiated tumors. Although rare, recent research shows that combining radiation with immunotherapies, such as immune checkpoint inhibitors, can enhance this effect. The interaction between radiation-induced cell death, immune responses, and the tumor microenvironment manifests in competing biologic mechanisms resulting in complex immunologic outcomes. In order to maximize the therapeutic advantages of the immunogenic effect of RT in the future, further studies are needed to fully understand its biologic underpinnings.