Inclusion Criteria:

• Age ≥ 18 years old.
• Histological or cytological confirmation of solid tumor malignancy and/or clinical history of known or suspected metastatic disease with an intraparenchymal brain tumor consistent with brain metastasis based on clinical and radiologic findings.
• Clinical indication for surgical resection of one brain metastasis based on neurosurgery recommendation and patient deemed a surgical candidate.
• Clinical indication and plan for stereotactic radiosurgery to all known brain lesions requiring treatment (< 10 metastases).
• ECOG Performance Status (PS) ≤ 2.       
• Provide written informed consent or have a Legally Authorized Representative who is responsible for the care and well-being of the potential study participant, provide consent.     
• Willing to return to enrolling institution for follow-up (during the Active Monitoring Phase of the study) or agreement to complete pre-specified MRI series and follow-up visits according to the study timeline mailing in digital copies of images as well as clinical notes.

Exclusion Criteria:

• Any of the following:
  • Pregnant women;
  • Nursing women;
  • Men or women of childbearing potential who are unwilling to employ adequate contraception.
• Co-morbid systemic illnesses or other severe concurrent disease which, in the judgment of the investigator, would make the patient inappropriate for entry into this study or interfere significantly with the proper assessment of safety and toxicity of the prescribed regimens.
• Immunocompromised patients and patients known to be HIV positive and currently receiving antiretroviral therapy.
  • Note: Patients known to be HIV positive, but without clinical evidence of an immunocompromised state, are eligible for this trial.
• Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
• Prior open neurosurgery for malignancy.
• Known or clinically suspected primary germ cell tumor, small cell carcinoma, or lymphoma.
• History of Whole Brain Radiation Therapy (WBRT).
• Known allergy to gadolinium, pacemaker, or other contraindication such as metal implant that is not safe for MRI.  Patients with MRI-compatible implants including MRI compatible pacemakers are eligible.
• Leptomeningeal metastasis/disease.
• A brain metastasis that is located ≤ 5 mm of the optic chiasm.
• Any brain metastasis > 5cm in size.
• >10 brain metastases.
• Indication for surgical resection of ≥ 2 brain metastases. 
• Indication for long-term (anticipated greater than 4 weeks) 4mg dexamethasone equivalent of steroids or bevacizumab.
• Actively enrolled on another brain metastases trial that is assessing the efficacy of either radiation or surgical interventions.

Eligibility last updated 1/25/24. Questions regarding updates should be directed to the study team contact.