To quantify motion based variation of the target volume of the primary tumor over the course of chemoradiotherapy in esophageal cancer patients, and to use this information to calculate appropriate PTV (planning target volume) margins according to the margins recipe for patients receiving trimodality (neoadjuvant chemoradiation and surgery) or definitive chemoradiation in order to personalize radiation treatment, resulting in either better target coverage or a reduction in normal tissue radiation exposure.
A single center prospective observational study will be performed in esophageal cancer patients. This study registers motion of the esophageal tumor, using 4D planning CT scans and repeated 4D CBCT scanning. Motion of fiducial markers inserted into the esophageal wall, will be used as a surrogate for tumor motion in the limited image quality of CBCT scans. Patients planned for trimodality treatment will additionally be imaged by serial 4D Pet CT and MRI in week 0 (before start chemoradiotherapy), week 3 (during chemoradiotherapy) and week 10 (just prior to surgery) to observe (early) signs of tumor response. Patients planned for definitive chemoradiation will not receive extra MRI imaging during treatment because of the inability to correlate this imaging with pathological response.
Study Type
OBSERVATIONAL
Enrollment
80
Insertion of Fiducial markers in esophageal wall.
The Netherlands cancer Institute
Amsterdam, North Holland, Netherlands
To quantify motion of the esophageal tumor over the course of chemoradiation
The outcome measures will be assessed by tracking the motion of the fiducial markers at the daily 4D CBCT (four dimensional cone beam CT scan). (primary outcome) By observing the motion of the fiducial, the exact setup error, breathing motion amplitudes, intra- and inter-fraction motion can be assessed.
Time frame: 6 weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.