Voxel Based Diffusion Tensor Imaging in Predicting Response in Patients With Brain Metastases Undergoing Whole Brain Radiation Therapy or Stereotactic Radiosurgery

Inclusion Criteria:

* Patients with multiple lesions from solid tumors on clinical MRI diagnosing the brain metastases may be treated with either WBRT or SRS if clinically indicated at the time of presentation but not both
* Karnofsky performance status (KPS) \>= 70
* Patients presenting with brain metastases from a newly diagnosed cancer may have systemic disease (brain disease at the time of initial cancer diagnosis)
* Patients with a history of cancer, but newly diagnosed brain metastases must have clinically stable systemic disease
* If a biopsy is performed, the patient has to be at least 1 week post-biopsy
* The patient must be able to commit to diffusion-weighted magnetic resonance (MR) imaging, diffusion tensor imaging (DTI), and chemical shift imaging (CSI) prior to treatment, after the first week of treatment, and 7-11 days after the completion of treatment at the Magnetic Resonance Research Center (MRRC)
* Patients undergoing SRS without WBRT must be able to commit to diffusion-weighted MR imaging, DTI, and CSI prior to treatment, and 7-11 days after the completion of the SRS treatment at the MRRC
* The patient must also be able to commit to post-treatment follow-up visits at Montefiore Medical Center involving serial MR imaging; the follow-up visits are to occur bimonthly for 6 months and then every 6 months until death

Exclusion Criteria:

* Any medical condition, which would make the imaging studies or WBRT unsafe or poorly tolerated
* Patient is receiving concurrent chemotherapy
* Known allergic reaction to contrast or shellfish
* Patients with brain metastases to be treated with radiosurgery
* Patients with brain metastasis resulting from hematologic malignancies and small cell lung cancer
* Implanted metal devices or foreign bodies that serve as a contraindication to MR imaging
* Creatinine \> 1.4 mg/dl and creatinine clearance \< 20 mg/dl
* Uncontrolled, clinically significant cardiac arrhythmias
* Severe claustrophobia
* Pregnant female
* Any prior radiation therapy to the brain
* KPS \< 70
* Patients with leptomeningeal disease