ABSTRACT
Numerous studies revealed that radiation can promote the immunogenic cell death, enhance the immune response of tu-mor-antigen-specific T cells, and induce systematic antitumor immunity, which may result in abscopal effect. Abscopal effect refers to the regression of non-irradiated metastatic lesions distant from the primary tumor site that is directly subjected to irradiation. Despite that abscopal effect has been clinically reported and that many preclinical studies have confirmed its biological basis, abscopal effect remains a subclinical phenomenon, in which objective efficacy is difficult to obtain. Currently, the anti-PD-1/PD-L1 therapy in clinical applications shows a clear and definite curative effect, thereby making local radiotherapy combined with immunotherapy a new treat-ment pattern. However, the clinical practice of this new mode should be based on appropriate dose and fraction and the most suitable temporal combination to achieve the synergic antitumor immune response.