Abscopal effect: A promising paradigm for managing metastatic cancer

The abscopal effects (AEs), characterized by tumor regression beyond the site of local treatment, represents a promising therapeutic approach for metastatic cancer. Initially employed as a palliative measure for advanced disease, local antitumor therapy has been shown to elicit AEs through the activation of antitumor immunity. This review provides an in-depth exploration of reports on the induction of AEs, their mechanisms, predicators and enhancement strategies. Various local treatment modalities can induce immunogenic cell death in tumor cells, thereby triggering immune-mediated distant antitumor effects. Although abscopal effects is rarely induced by local treatment alone, several approaches have been developed to potentiate it. This review summarizes these enhancement strategies, discusses existing knowledge gaps, and highlights the substantial clinical potential of abscopal effects.