In light of this new technology and preliminary findings of low toxicity of online, adaptive, magnetic resonance (M)-guided stereotactic radiation on a single arm prospective study, the investigators propose to compare this technique to online MR-guided stereotactic body radiation therapy (SBRT) without adaptation. Online plan adaptation increases treatment times for patients and comprises an increased burden on technical and clinical staff. Although preliminary trial results are encouraging, it remains unclear if the dosimetric benefits of online-adaptive planning studies will translate to measurable improvements in clinical outcomes that merit its routine use. In our preliminary study, plan adaptation was most often required when tumors were adjacent to the gastrointestinal tract (the esophagus to the sigmoid colon), as those structures were most commonly the dose-limiting structures and were noted to change in location on a day-to-day basis. For these reasons, abdominal disease sites have historically highlighted the limitations of SBRT. Specifically, the investigators will enroll patients with oligometastatic or unresectable primary disease of the non-liver abdomen to a randomized, prospective trial.