A brain tumor is a collection, or mass, of abnormal cells in your brain. Your skull, which encloses your brain, is very rigid. Any growth inside such a restricted space can cause problems. Brain tumors can be cancerous (malignant) or noncancerous (benign). When benign or malignant tumors grow, they can cause the pressure inside your skull to increase. This can cause brain damage, and it can be life-threatening.
Brain tumors are categorized as primary or secondary. A primary brain tumor originates in your brain. Many primary brain tumors are benign. A secondary brain tumor, also known as a metastatic brain tumor, occurs when cancer cells spread to your brain from another organ, such as your lung or breast.
Primary brain tumors : Primary brain tumors originate in your brain.
- brain cells
- the membranes that surround your brain, which are called meninges
- nerve cells
- Secondary brain tumors
Secondary brain tumors : make up the majority of brain cancers. They start in one part of the body and spread, or metastasize, to the brain. The following can metastasize to the brain:
- lung cancer
- breast cancer
- kidney cancer
- skin cancer