Causes
The exact cause of cancer is unknown. Brain cancer that originates in the brain is called a primary brain tumor. It can spread and destroy nearby parts of the brain. Cancers of the breast, lung, skin, or blood cells (leukemia or lymphoma) can also spread (metastasize) to the brain, causing metastatic brain cancer. These groups of cancer cells can then grow in a single area or in different parts of the brain.