Adjuvant Durvalumab for Esophageal Cancer

Inclusion Criteria: * Histologically confirmed squamous esophageal cancer, irrespective of PD-L1 status * The enrolment should be done during the time interval from 20 days to 56 days after complete resection after neoadjvuant CCRT (no residual tumor after operation) * Clinical tumor stage before neoadjuvant CCRT should be T3-4N0M0 or T1-4N1-3M0 * Available tumor specimen for biomarker analysis acquired before neoadjuvant CCRT or at operation Exclusion Criteria: * Other PD-1 or PD-L1 inhibitors history * Mean QT interval corrected for heart rate (QTc) ≥470 ms using Bazett's correction * Current or prior use of immunosuppressive medication within 28 days before the first dose of MEDI4736, with the exceptions of intranasal and inhaled corticosteroids or systemic corticosteroids at physiological doses, which are not to exceed 10 mg/day of prednisone, or an equivalent corticosteroid * Active or prior documented autoimmune disease within the past 2 years NOTE: Subjects with vitiligo, Grave's disease, or psoriasis not requiring systemic treatment (within the past 2 years) are not excluded