Imaging-guided proton therapy for gastrointestinal tumors

This chapter is dedicated to image-guided proton therapy in gastrointestinal (GI) cancers. We first introduce the physics governing protons interacting with matter, followed by discussing the advantages and disadvantages of proton therapy compared to conventional external beam radiotherapy. We also present the clinical indications and manifestation of proton therapy in some predominant forms of GI cancers. We then elaborate on the imaging and motion management modalities used for patient setup and plan adaptation in proton therapy. Ultimately, the planning and delivery of proton radiotherapy is briefly summarized.