Targeting two radiation-induced immunosuppressive pathways to improve the efficacy of normofractionated radiation therapy in a preclinical colorectal cancer model.

Purpose: We have previously demonstrated in a murine colorectal cancer model that normofractionated RT (normoRT: 18 × 2 Gy) induced MDSC infiltration and PD-L1 expression, while hypofractionated RT (hypoRT: 3 × 8 Gy) induced Treg. Here, we wanted to assess whether the association of normoRT with treatments that target two radiation-induced immunosuppressive pathways (MDSC and PD-L1) could improve tumor control.

Materials And Methods: Subcutaneous tumors were induced using colon tumor cells (CT26) in immunocompetent mice (BALB/c) and were treated with RT alone (18 × 2 Gy or 3 × 8 Gy), or concomitantly with 5-Fluorouracil (5FU) (10 mg/kg) to deplete MDSC, and/or anti-PD-L1 (10 mg/kg).

Stereotactic body radiotherapy for extra-cranial oligoprogressive or oligorecurrent small-cell lung cancer.

Introduction: The role of local ablative treatments, including stereotactic body radiotherapy (SBRT), is an area of active research in oligometastatic patients. Small cell lung cancer (SCLC) has a poor prognosis, with common diffuse metastatic evolution. We evaluated the outcomes after SBRT in uncommon oligoprogressive/oligorecurrent SCLC presentation.

FFCD 1709-SIRTCI phase II trial: Selective internal radiation therapy plus Xelox, Bevacizumab and Atezolizumab in liver-dominant metastatic colorectal cancer.

Immune checkpoint inhibitors (ICI) have high efficacy in metastatic colorectal cancer (mCRC) with microsatellite instability (MSI) but not in microsatellite stable (MSS) tumour due to the low tumour mutational burden. Selective internal radiation therapy (SIRT) could enhance neoantigen production thus triggering systemic anti-tumoral immune response (abscopal effect). In addition, Oxalipatin can induce immunogenic cell death and Bevacizumab can decrease the exhaustion of tumour infiltrating lymphocyte.

Comparison between tumour metabolism derived from F-FDG PET/CT and accurate cytogenetic stratification in newly diagnosed multiple myeloma patients.

Background: F-fluorodeoxyglucose positron emission tomography integrated with computed tomography (F-FDG PET/CT) is a useful tool for baseline staging in newly diagnosed multiple myeloma (MM) but also for prognostic stratification. This monocentric retrospective study aimed at examining the relation between baseline tumour metabolism assessed by F-FDG PET/CT and linear predictor (LP) score, a new cytogenetic stratification score.

Methods: From March 2012 to March 2019, 57 patients with newly diagnosed MM addressed to our institution for baseline F-FDG PET/CT were included.

[Abscopal effect: Myth or reality?].

The abscopal effect has been mentioned since 1953. The increase in knowledge about the immune system and the development of immunotherapies support its potential therapeutic interest. While it is accepted that radiotherapy induces an immune response, demonstrating its systemic impact is not easy.

Impact of proton therapy on antitumor immune response.

Radiotherapy delivered using photons induces an immune response that leads to modulation of the tumor microenvironment. Clinical studies are ongoing to evaluate immune checkpoint inhibitors in association with photon radiotherapy. At present, there is no publication on the radio-induced immune response after proton therapy.

Radiotherapy Scheme Effect on PD-L1 Expression for Locally Advanced Rectal Cancer.

In locally advanced rectal cancer, radiotherapy (RT) followed by surgery have improved locoregional control, but distant recurrences remain frequent. Although checkpoint inhibitors have demonstrated objective response in several cancers, the clinical benefit of PD-1/PD-L1 blockade remains uncertain in rectal cancer. We collected data from biopsies and surgical specimens in 74 patients.

and impact of high-dose rate radiotherapy using flattening-filter-free beams on the anti-tumor immune response.

Introduction: Modern accelerators have the "flattening filter-free" (FFF) technique to deliver RT with a moderate high-dose rate, currently used in limited clinical indications. No scientifically established data are currently available on the possible effects of this high dose rate on the anti-tumor immune response. We therefore propose here to study these effects in a preclinical CT26 murine colorectal tumor model.

Quality Assurance of Dose-Escalated Radiation Therapy in a Randomized Trial for Locally Advanced Oesophageal cancer.

Purpose: The ongoing phase 2/3 PRODIGE 26/CONCORDE trial compares chemoradiation therapy with and without dose escalation in patients with locally advanced or unresectable esophageal cancer. The results of a benchmark case procedure are reported here to evaluate the protocol compliance of participating centers as part of quality assurance for radiation therapy.

Methods And Materials: Volume delineation, target coverage, and dose constraints to the organs at risk (OARs) were assessed on treatment plans of a common benchmark case performed by each participating center.

Optimized fractionated radiotherapy with anti-PD-L1 and anti-TIGIT: a promising new combination.

Purpose/objective: Radiotherapy (RT) induces an immunogenic antitumor response, but also some immunosuppressive barriers. It remains unclear how different fractionation protocols can modulate the immune microenvironment. Clinical studies are ongoing to evaluate immune checkpoint inhibitors (ICI) in association with RT.

The 6th R of Radiobiology: Reactivation of Anti-Tumor Immune Response.

Historically, the 4Rs and then the 5Rs of radiobiology explained the effect of radiation therapy (RT) fractionation on the treatment efficacy. These 5Rs are: Repair, Redistribution, Reoxygenation, Repopulation and, more recently, intrinsic Radiosensitivity. Advances in radiobiology have demonstrated that RT is able to modify the tumor micro environment (TME) and to induce a local and systemic (abscopal effect) immune response.

Patterns of Bone Failure in Localized Prostate Cancer Previously Irradiated: The Preventive Role of External Radiotherapy on Pelvic Bone Metastases.

External beam radiation therapy (EBRT) can cure localized prostate cancer (PCa) by sterilizing cancer cells in the prostate gland and surrounding tissues at risk of microscopic dissemination. We hypothesized that pelvic EBRT for localized PCa might have an unexpected prophylactic impact on the occurrence of pelvic bone metastases. We reviewed the data of 332 metastatic PCa patients.

Salvage extended field or involved field nodal irradiation in F-fluorocholine PET/CT oligorecurrent nodal failures from prostate cancer.

Purpose: The concept of metastasis-directed therapy for nodal oligorecurrences with stereotactic body radiotherapy is increasingly accepted. Hence, the comparison between salvage extended field radiotherapy (s-EFRT) and salvage involved field radiotherapy (s-IFRT) in patients with F-fluorocholine (FCH) PET/CT+ nodal oligorecurrences from prostate cancer is worthy of investigation.

Methods: Patients with oligorecurrent nodes on FCH PET/CT treated with salvage radiotherapy between 2009 and 2017 in a single tertiary cancer centre were selected for this study.