Association of Radiochemotherapy and Immunotherapy for the Treatment of Unresectable Oesophageal caNcer

ARION study will randomize 120 patients, in 12 centers in France, according to a ratio 1:1 in the following arm of treatment: ‐ Standard and experimental arm: Definitive modulated‐intensity radiotherapy will be delivered according to boost integrated technique 5 days a week for 5 weeks at a dose of: ‐ 50 Gy delivered in 25 fractions to the macroscopic disease (endoscopic, TDM and fused FDG PET) ‐ 45 Gy to the adjacent peri tumoral mucosis and prophylactic lymph node FOLFOX 4 simplified protocol, 1 infusion every 2 weeks (q2w) during 3 months starting with radiotherapy (+/‐ 1 day): ‐ IV oxaliplatin 85 mg/m² in 2 h on day 1 (D1) ‐ IV Leucovorin 200 mg/m² in 2 h on D1, followed by ‐ IV 5‐FU 400 mg/m² in 10 minutes on D1 followed by ‐ IV continuous infusion 5‐FU 2400 mg/m² in 46 h ‐ Experimental arm: Concomitant administration of durvalumab: Every 4 weeks during concurrent FOLFOX (dose: 1500 mg) and after FOLFOX completion (total of 12 months of treatment).