A Study to Evaluate Nivolumab in the Treatment of Early Stage Esophageal or Gastroesophageal Cancer

Inclusion Criteria

• Must provide voluntary informed consent to participate in the study before inclusion in the study
• Must have confirmed diagnosis of resected early stage (Stage II/III) EC or GEJC (histologically or cytologically confirmed stage)
• Physician decision to treat the participant with adjuvant nivolumab (according to the local label as per country-specific regulations) must be made prior to and independently of participation in the study

Exclusion Criteria

• Participation in a clinical trial of an investigational drug, concurrently or within the last 30 days (Participants who have completed their participation in an interventional trial and who are only followed-up for OS can be enrolled.)
• Prior treatment with immuno-oncologic agents, including nivolumab, for any indication
• Participants with a current primary diagnosis of a cancer other than EC or GEJC that requires systemic or other treatment, or has not been treated curatively (as per discretion of the investigator)