Brain tumors can be classified in many ways. The most common brain tumor is called a metastasis. These tumors spread to the brain from another organ in the body. The most common tumor that starts in the brain is called an astrocytoma.
Symptoms of a brain tumor depend on its size and location. However, common symptoms include focal neurological signs (speech problems, numbness, weakness, visual problems), mood and personality changes, seizures, or symptoms of increased brain pressure such as nausea, vomiting, or headache.
Usually when these symptoms arise, imaging of the brain is performed. The initial step is often a CT scan. If there is something suspicious on the CT, a MRI is performed.