Figure 2.

Abscopal effect induced by local radiation can be enhanced when combined with immune checkpoint inhibitors. When local radiation is delivered to the primary tumor, tumor-associated Ag are released from dead tumor cells and processed by APC such as DC. APCs then traffic to the lymph nodes and present Ags to naïve T cells which are activated and start to proliferate. A large number of activated T cells especially CTLs migrate and traffic to the tumor site and exert cytolysis of tumor cells. The SMART approach with an accelerated hypofractionated hemithoracic radiation followed by surgery could therefore provide an excellent platform to introduce immunotherapy in clinical practice. Ag, antigens; APC, antigen presenting cells; DC, dendritic cells; EPP, extrapleural pneumonectomy.