This study looks at treating people with cancer that has spread to the brain, called brain metastases. It compares two treatments: one where patients get stereotactic radiosurgery (SRS) before surgery, and one where they get it after. SRS is a special type of radiation that targets only the cancer in the brain, leaving normal brain tissue safe. This study will help doctors understand if giving SRS before surgery might be better for stopping tumor growth and improving symptoms.

• Participation involves surgery and one session of SRS, either before or after surgery.
• The study lasts for about two years with regular follow-ups.
• Participants must be 18 or older, able to have surgery and SRS, and must not have had prior brain radiation at the surgery site.

To join, you need to have 1-4 brain metastases, one of which needs surgery. Your cancer should not be near the brain's sensitive parts like the brainstem or optic chiasm. You must be healthy enough for surgery and SRS and agree to use contraception during the study if needed. Past treatments like whole brain radiation could exclude you. This research helps find the best way to use surgery and radiation together for brain metastases.