Poor accrual. Investigator decision.

Cancer which spreads to the brain (brain metastases) is a common and significant problem. Historically, whole-brain radiotherapy has been used to treat these patients but has a negative effect on cognition. Radiosurgery is an alternative treatment with potential for fewer cognitive side effects. The impact of radiosurgery alone on the cognitive function of patients with multiple brain metastases is not well studied. We propose a pilot study at the Winnipeg Centre for Gamma Knife Surgery to examine this issue.

Patients with >=4 brain metastases will undergo Gamma Knife radiosurgery to a dose of 15-20 Gy, depending on the maximum tumour diameter and number of metastases. A number of neurocognitive, quality of life, and toxicity assessments will be performed at baseline and at 6 weeks post-radiosurgery, then at months 4, 6, 12, 18, and every 6 months thereafter.

Inclusion Criteria:

• Pathologically proven solid tumour malignancy
• Age >= 18 years
• Karnofsky performance status >= 70
• >= 4 brain metastases, all eligible to be treated with radiosurgery
• All brain metastases <= 4.0 cm in any diameter
• Pre-treatment contrast enhanced MRI brain <= 42 days prior to enrollment
• Patient able to provide his/her own written informed consent

Exclusion Criteria:

• Prior radiosurgery, whole brain radiotherapy, or cranial radiotherapy
• Previous surgical resection of brain metastasis (biopsy is allowed)
• Prior chemotherapy ≤ 7 days prior to enrollment
• Planned chemotherapy during radiosurgery
• Leukemia, lymphoma, germ-cell tumour, small-cell lung cancer diagnosis
• Brainstem metastasis
• Leptomeningeal metastases
• Contraindication to MR imaging with contrast
• Pregnant or nursing women

Patients with multiple (>= 4) brain metastases undergoing radiosurgery at the Winnipeg Centre for Gamma Knife Surgery.