Four or fewer brain metastases (as defined on the preoperative MRI brain scan) and status post resection of one of the lesions

Pathology from the resected brain metastasis must be consistent with a non-central nervous system primary site (NOTE: Patients with or without active disease outside the nervous system are eligible including patients with unknown primaries, as long as the pathology from the brain is consistent with a non-central nervous system primary site.)

Any unresected lesions must measure <=3.0 cm in maximal extent on the contrasted preoperative treatment MRI brain scan obtained <=35 days prior to pre-registration (see Magnetic Resonance Imaging Guidelines, Section 11.2). The unresected lesions will be treated with SRS as outlined in the treatment section (Section 7.0) of the protocol. (NOTE: The metastases size restriction does not apply to the resected brain metastasis; with resected brain metastasis only surgical cavity size determines eligibility see 3.114)

Resection cavity must measure <5.0 cm in maximal extent on the postoperative MRI (or CT) brain scan obtained <=35 days prior to pre-registration (NOTE: It is permissible for the resection of a dominant brain metastasis to include a smaller "satellite" metastasis as long as the single resection cavity is less than the maximum size requirements.)

All standard tumor-staging procedures necessary to define baseline extracranial disease status completed <=42 days prior to pre-registration

Ability to be treated with either a gamma knife or a linear accelerator-based radiosurgery system

Age >= 18 years

Age (=)

Willing and able to complete neurocognitive examination without assistance

Willing and able to complete QOL by themselves or with assistance (see Section 4.0)

ECOG performance status (PS) 0, 1, or 2

ECOG Performance Status (=)

SRS facility is Radiological Physics Center (RPC) approved (see Section 6.24)

The Neurocognitive Testing examiner must have credentialing confirming completion of the neurocognitive testing training (see Section 6.25)

Provide informed written consent

Willing to provide blood and urine samples for correlative research purposes (see Sections 6.0 and 14.0)

Any of the following: Pregnant women Nursing women Men or women of childbearing potential who are unwilling to employ adequate contraception throughout the study and for men for up to 3 months after completing treatment

Prior cranial RT (radiation therapy)

Inability to complete an MRI with contrast of the head

Known allergy to gadolinium

Planned cytotoxic chemotherapy during the SRS and WBRT

Primary germ cell tumor, small cell carcinoma, or lymphoma

Widespread definitive leptomeningeal metastasis

A brain metastasis that is located <=5 mm of the optic chiasm or within the brainstem

Consent form signed and dated

Date Informed Consent Signed (mm/dd/yyyy)

Authorization for use and disclosure of protected health information signed and dated (Non-USA institution only check NA)

Date of authorization (mm/dd/yyyy)

A mandatory correlative research component for blood and urine is part of this study; the patient will be automatically registered onto this component (see Sections 3.119f and 14.0)

Pre-registration tests/procedures must be completed <=14 days prior to pre-registration (see Section 4.0)

Earliest pre-registration test date (mm/dd/yyyy NOTE: The earliest pre-registration test date must be less than or equal to the latest pre-registration test date. The above dates DO NOT include footnote 9 of the test schedule that reads "All standard tumor-staging procedures necessary to define baseline extracranial status as deemed appropriate by the treating oncology physician completed <=42 days prior to pre-registration.")

Latest pre-registration test date (mm/dd/yyyy)

All required baseline symptoms (see Section 10.3) must be documented and graded

A radiation oncologist has seen the patient and confirms the patient is a suitable candidate for this study

Blood/urine kits available on site

Patient Questionnaire Booklet-Quality of Life (QOL) and Patient and Examiner Questionnaire Booklet-Neurocognitive Evaluations are available on site; copies are not acceptable for this submission

Patient has given permission to store and use his/her blood samples for use in future research to learn about, prevent, or treat cancer

Patient has given permission to store and use his/her blood samples for use in future research to learn about, prevent, or treat other health problems (for example: diabetes, Alzheimer's disease, or heart disease.)

Patient has given permission for NCCTG to give his/her stored blood samples for use in future research to outside researchers

Patient has given permission to store and use his/her urine samples for use in future research to learn about, prevent, or treat cancer

Patient has given permission to store and use his/her urine samples for use in future research to learn about, prevent, or treat other health problems (for example: diabetes, Alzheimer's disease, or heart disease.)

Patient has given permission for NCCTG to give his/her stored urine samples for use in future research to outside researchers

Patient has given permission to store and use his/her tissue samples for use in future research to learn about, prevent, or treat cancer

Patient has given permission to store and use his/her tissue samples for use in future research to learn about, prevent, or treat other health problems (for example: diabetes, Alzheimer's disease, or heart disease.)

Patient has given permission for NCCTG to give his/her stored tissue samples for use in future research to outside researchers