Evaluate the potential role of PET/MRI as a predictor of esophageal and junctional cancers in response to neoadjuvant chemoradiotherapy (nCRT).

This is a prospective, observational single center study which plans to enroll patients with biopsy proven potentially resectable esophageal or junctional cancer scheduled to receive nCRT (CROSS regimen) prior to surgery.

The study aims to evaluate Routine pre-treatment work-up includes PET to stage the tumour extension.

• PET/MRI (Magnetic resonance imaging) will replace the PET component of CT(computed tomography)
• An additional intermediate 18-FDG (Fluorodeoxyglucose) PET/MRI will be performed during nCRT
• Post nCRT imaging, as required prior to surgery, will be PET/MRI six weeks after treatment completion.
• 8-12 weeks post nCRT completion surgery will be performed, based on each patient's performance status and response to nCRT
• Histopathological samples of the excised tumor and lymph nodes will be used for diagnosis, staging and description of qualitative and quantitative parameters Routine clinical and radiological follow-up for 24 months (for the scope of this study) will follow the standard clinical workflow assigned to this group of patients.

Inclusion Criteria:

• biopsy-proven esophageal or junctional carcinomas (either adenocarcinoma (AC) or squamous cell carcinoma (SCC) for which an Ivor-Lewis transthoracic esophagectomy with supramesocolic and mediastinal lymphadenectomy is indicated;
• visible tumor on pre-treatment imaging;
• ≥ 18 years of age;
• signed informed consent.

Exclusion Criteria:

• - incomplete preoperative imaging assessment;
• contraindications to neoadjuvant treatment;
• contraindications to preoperative imaging (such as pacemaker, allergy to contrast agents);
• inability to complete imaging examinations (i.e. severe claustrophobia);
• contraindication to surgery (comorbidities, distant metastatic disease (imaging confirmed));
• pregnant or lactating women
• severe hypersensitivity to gadobutrol or fludeoxyglucose F18.