| The primary aim of this study is to determine the value of the addition of FDG-PET to the current CT-based radiotherapy treatment planning of patients with esophageal or GEJ cancer. The primary research questions are: 1. In what proportion of patients with a locoregional recurrence, observed at 6 or 12 months after treatment, can the recurrence be considered a possibly preventable recurrence if PET/CT-based treatment planning was used instead of CT-based treatment planning alone? 2. What is the disease free survival at 6 and 12 months both for the entire group and for the subgroups based on recurrence localisation inside or outside the CT-based CTV? Secondary Objectives 1. What is the interobserver variability of defined GTV, CTV and PTV? 2. What is the size of GTV, CTV and PTV for CT-based and PET/CT-based treatment planning? 3. How is the dose distribution in risk organs, including lung (Mean lung dose, V20), heart (V30) and calculation of NTCP values (Normal Tissue Complication Probability) comparing 3D-CRT and IMRT and IGRT with and without PET/CT-based treatment planning? 4. What are the costs of radiotherapy planning and treatment (surgical and/or chemoradiation), complications and recurrence-related treatment or the prevention thereof? 5. How many patients develop distant metastases after treatment? |
