Ablative Stereotactic MR-Guided Adaptive Reirradiation

Exclusion Criteria

• •Contraindication to having an MRI scan.
• •Lesion that would receive study therapy arises from or invades a gastrointestinal (GI) luminal organ (a lesion abutting but not invading a GI luminal organ is permitted)
• •Lesion that would receive study therapy is not located in the abdomen or pelvis.
• •\> 1 course of overlapping radiation therapy delivered to the abdomen or pelvis.
• •\< 70% of the gross tumor volume (GTV) receives at least the 95% of the prescribed dose on the original plan using the simulation day anatomy.
• •More than 1 lesion in the abdomen or pelvis that requires reirradiation.
• •History of inflammatory bowel disease.
• •Unable to acquire DICOM radiation therapy treatment plan from the prior radiation therapy.
• •Unresolved grade 2+ toxicity (Common Terminology Criteria for Adverse Events version 5.0) from previous anti-cancer therapy.
• •Any condition in the opinion of the investigator that would interfere with evaluation of study treatment or interpretation of participant safety or study results.
• •Individuals who are pregnant.
• •Chemotherapy given within 1 week prior to or following reirradiation.
• •Vascular endothelial growth factor (VEGF) inhibitor given within 8 weeks prior to or following reirradiation