Magnetic resonance imaging (MRI) scans of the brain and spine must be completed within 21 days prior to patient registration; all MRI scans should be with and without gadolinium All patients who do not have surgery performed must have MRI scans obtained prior to induction Patients must be able to have MRI scans Unable to undergo MRI scans Evidence of intratumoral or peritumoral hemorrhage on baseline MRI scan other than those that are grade =< 1 and either post-operative or stable on at least 2 consecutive MRI scans All subjects must have MRI scans of the brain within 28 days prior to registration; an MRI of the spine should be performed if clinically indicated Clinical evidence of extra-capsular extension on scans. Must be able to undergo serial MRI scans for response evaluation Patient must be able to undergo MRI and PET scans Must be willing and able to undergo three research PET scans Unable to undergo MRI scans with contrast Must be willing and able to undergo three research PET scans Must be willing and able to undergo two research MRI scans, one before study treatment begins and another shortly after SBRT Must be able and willing to undergo two MRI scans, before study treatment begins and shortly after first dose of radiation (only mandatory for first 10 patients who have no contra-indications for MRI Unable to undergo MRI scans (e.g., embedded ferromagnetic metal or pacemakers) Magnetic resonance imaging (MRI) scans of the brain and spine must be completed within 14 days of patient registration; all MRI scans should be with and without gadolinium All patients who do not have surgery performed must have MRI scans obtained prior to induction Patients unable to undergo MR imaging because of non-compatible devices can be enrolled, provided CT scans are obtained and are of sufficient quality; patients without non-compatible devices may not have CT scans performed to meet this requirement Radiographic stability should be determined by comparing contrast-enhanced CT or MRI scans at screening to scans obtained by the same method at least 4 weeks earlier Participants must be willing and able to undergo regular magnetic resonance imaging (MRI) scans of the brain Has evidence of intratumoral or peritumoral hemorrhage on baseline MRI scan other than those that are grade =< 1 and either post-operative or stable on at least 2 consecutive MRI scans Patients must be able to tolerate MRI scans Patients must be able to undergo contrast enhanced magnetic resonance imaging (MRI) scans (or contrast enhanced computed tomography [CT] scans for patients unable to tolerate MRI) Able to undergo brain MRI scans Has evidence of intratumoral or peritumoral hemorrhage on baseline MRI scan other than those that are ?Grade 1 and either post-operative or stable on at least 2 consecutive MRI scans Metastatic disease on baseline staging scans Patients must be able to undergo contrast enhanced MRI scans (or contrast enhanced computed tomography [CT] scans for patients unable to tolerate MRI) Patients must be able to tolerate MRI/CT scans Able to undergo standard MRI scans with contrast agent Able to undergo standard MRI scans with contrast agent before enrollment and after treatment Patient must be able to undergo MRI and PET scans Patient must be able to undergo MRI and PET scans Inability to cooperate with the scans Patients able to tolerate PET/MRI scans Subjects with contraindications for receiving HIDA scans and MRI scans will not be eligible to participate in this study More than 6 MET PET scans within the previous 12 months Participants must be willing and able to undergo regular magnetic resonance imaging (MRI) scans of the brain Must be able to undergo MRI scans Patients who require sedation prior to MRI scans Radiographic confirmation of MBO is required prior to registration; scans may have been done before or after admission; scans done prior to admission must have been completed within 14 days prior to admission; computed tomography (CT) scans are preferred Participants must show evidence of disease progression within 12 months (an additional month will be allowed to accommodate actual dates of performance of screening scans, ie, within ?13 months) prior to signing informed consent, according to RECIST 1.1 assessed and confirmed by central radiographic review of CT and/or MRI scans.