Abscopal, immunological effects of radiotherapy: Narrowing the gap between clinical and preclinical experiences

[D.ap]

Abscopal, immunological effects of radiotherapy: Narrowing the gap between clinical and preclinical experiences


Summary
Radiotherapy—despite being a local therapy that meanwhile is characterized by an im- pressively high degree of spatial accuracy—can stimulate systemic phenomena which oc- casionally lead to regression and rejection of non-irradiated, distant tumor lesions. These abscopal effects of local irradiation have been observed in sporadic clinical case reports since the beginning of the 20th century, and extensive preclinical work has contributed to identify systemic anti-tumor immune responses as the underlying driving forces. Although abscopal tumor regression still remains a rare event in the radiotherapeutic routine, in- creasing numbers of cases are being reported, particularly since the clinical implementa- tion of immune checkpoint inhibiting agents. Accordingly, interests to systematically exploit the therapeutic potential of radiotherapy-stimulated systemic responses are con- stantly growing. The present review briefly delineates the history of radiotherapy-induced abscopal effects and the activation of systemic anti-tumor immune responses by local ir- radiation. We discuss preclinical and clinical reports with specific focus on the correspond- ing controversies, and we propose issues that should be addressed in the future in order to narrow the gap between preclinical knowledge and clinical experiences.
KEYWORDS
abscopal effect, anti-tumor immunity, immunogenic cell death, radiotherapy



https://onlinelibrary.wiley.com/doi/pdf ... /imr.12573