REGULUS: MRI-guided Adaptive SABR for Liver Cancers

Inclusion Criteria: * Histologically confirmed HCC, intrahepatic cholangiocarcinoma, or metastatic cancer. In the case of suspected HCC in patients with known cirrhosis, noninvasive criteria recommended by the European Association for the Study of Liver Diseases (lesion \> 1 cm with arterial phase hyperenhancement and venous phase washout) or LI-RADS score of 5 may be used * ≥ 18 years old at time of study enrollment * Child-Pugh A status * Eastern Cooperative Oncology Group (ECOG) Performance Status of 0, 1, or 2 * Life Expectancy \> 6 months * For women of childbearing potential or who are not postmenopausal (see Appendix F for Definition of Menopausal Status), a negative urine or serum pregnancy test must be done. * Ability to understand and the willingness to provide written informed consent. * Patients treated with prior liver-directed therapies with the exception of radioembolization are eligible for this study if they otherwise meet eligibility criteria Exclusion Criteria: * Prior treatment with radioembolization * Cytotoxic chemotherapy or investigational agent within 1 week of SABR * Prior radiotherapy overlapping with study treatment site * Female patients who are pregnant * Contraindication to having an MRI scan or inability to tolerate MRI * Presence of a pacemaker or other implanted cardiac device * Direct tumor extension into the stomach, duodenum, small bowel or large bowel * Patient unable to breath hold \> 15 seconds