Assessment of Metabolic & Path Response w/ RCT & ImT Before Surgery in Locally Advanced Esoph and Gastro-esoph Jction CA

Monalizumab (IPH2201) is given at the recommended dose of 10 mg/kg, intravenously (infusion during 60 minutes) every two weeks

A total of 4 cycles of FOLFOX is administrated every 2 weeks with one cycle 15 days prior to the radiotherapy and 3 cycles during the radiotherapy whatever the level

A total of 4 cycles of FOLFOX is administrated every 2 weeks with one cycle 15 days prior to the radiotherapy and 3 cycles during the radiotherapy whatever the level

Radiation therapy must start the first day of FOLFOX chemotherapy. Radiation is given once daily for 5 consecutive days; on the days that the patient receives chemotherapy (and monalizumab when applicable), chemotherapy (and monalizumab) should be given prior to radiotherapy.

18-FDG-PET scan will be performed just before the beginning of radio-chemotherapy (D10-D14) and will be blinded for investigators and patients. Another 18-FDG-PET will be performed before surgery (surgery Day-5 to surgery Day -1) to exclude metastatic evolution

Surgery is performed preferably 8 weeks after the completion of the radio-chemotherapy, and it should not be performed less than one week after the last dose of monalizumab