The types of cancer that commonly spread to the brain are cancers of the lung, breast, unknown primary site, melanoma, and colon. About half of metastatic spinal cord tumors are caused by lung cancer.

Prognosis depends on the following:

• Whether the patient is younger than 60 years.
• Whether there are fewer than 3 tumors in the brain and/or spinal cord.
• The location of the tumors in the brain and/or spinal cord.
• How well the tumor responds to treatment.
• Whether the primary tumor continues to grow or spread.

The prognosis is better for brain metastases from breast cancer than from other types of primary cancer. The prognosis is worse for brain metastases from colon cancer.