Brain Tumors

Tumors that originate in the brain are a relatively rare form of cancer, with only about 18,500 new cases diagnosed in the United States each year. The outlook for these patients is not good because most types of brain tumors are malignant and difficult to fully remove. Brain tumors account for only 1.4% of all cancers, but 2.4% of all cancer-related deaths. The American Cancer Society estimates that about 12,760 people will die this year from malignant brain tumors. Tumors that start in other organs such as the lung or breast and then spread to the brain are called metastatic brain cancers. Fortunately, not all brain tumors are cancerous. Benign (noncancerous) tumors do not metastasize and, with very rare exceptions, are not life-threatening.

The brain consists of different kinds of tissues and cells. Treatment is determined by the "grade" or level of aggressiveness of the tumor and by the type of cells from which it grew. Common types of brain tumors include:

• Meningioma - tumors beginning in the layer of tissue that surrounds the brain
• Glioma - types of tumors from glial cells, including:
  • Astrocytomas - developing from astrocytes (a type of brain cell)
  • Oligodendrogliomas - starting in brain cells called oligodendrocytes
  • Ependymomas - arising from the ependymal cells lining the ventricles