Abscopal effect in the radio and immunotherapy

Area of Science:

• Oncology
• Radiation Oncology
• Immunology

Background:

• The abscopal effect describes tumor regression in non-irradiated areas following radiation therapy.
• This phenomenon is rare but shows promise, particularly in combination cancer treatments.
• Recent advances in immunotherapy, especially immune checkpoint inhibitors, have renewed interest in the abscopal effect.

Purpose of the Study:

• To review and systematize reported cases of the abscopal effect from 1969 to 2019.
• To explore potential mechanisms underlying the abscopal effect.
• To investigate the frequency and role of the abscopal effect in radio/immunotherapy.

Main Methods:

• Systematic literature review of published cases and studies.
• Analysis of reported abscopal effect occurrences across various cancer localizations.
• Compilation of data on potential mechanisms and therapeutic contexts.

Main Results:

• The review covers documented instances of the abscopal effect in diverse clinical settings.
• Emerging evidence suggests a link between immune checkpoint blockade and the abscopal effect.
• The phenomenon remains poorly understood, necessitating further research into its biological underpinnings.

Conclusions:

• The abscopal effect, though rare, represents a significant area of research in oncology.
• Combination radio/immunotherapy may enhance the occurrence and efficacy of the abscopal effect.
• Further investigation into the abscopal effect's mechanisms is crucial for optimizing cancer treatment strategies.