Phase II Trial Assessing the Efficacy of Immuno-Radiation Abscopal Effect in Patients With Metastatic Cancers

Nowadays, metastatic cancer treatment is evolving with systemic treatments (target therapies and immunotherapies). Combinations and new therapeutic schemes have recently boosted the interest for an effect called "abscopal". This effect is based on the immune-stimulating effect of high doses ionizing radiations, but also on synergistic association with systemic treatment with immunologic mechanisms. This effect could enhance the tumor local control, but also its distant control. Numerous preclinical evidences as well as some clinical case reports described the abscopal effect. Ongoing clinical studies are investigating with radiotherapy abscopal effect alone, or associated with immunotherapies (anti-CTLA-4, PD-1 or PDL-1). The present study proposes a new association, based on an original biological rational. The proposed theory is based on combination of radiation therapy with usual targeted therapies capable of ADCC (Antibody-Dependant Cell Cytotoxicity). This association could enhance in an additive/synergistic way the benefic impact of immune system activation on tumor control. In the present study, Stereotactic Body Radio-Therapy (SBRT) will be combined to the standard systemic treatment for first line treatment of metastatic breast, colorectal and VADS (upper aerodigestive tract) cancers. Indeed, these treatments have in common the use of target therapies capable of ADCC. The IRAM study objective is to highlight a possible abscopal effect of this combination for metastatic cancer patients.