When most normal cells in the human body grow old or are damaged, they die, and the body produces new cells to take their place. When this process goes wrong, the body sometimes produces new cells even if they aren't needed and old cells do not die off. A mass of tissue cells can occur, and this buildup is called a growth or tumor.
There are two types of brain tumors:
- Do not contain cancer cells.
- Can usually be removed, and seldom grow back.
- Rarely spread to other parts of the body, or invade tissues around them. However, benign tumors can press on sensitive areas of the brain and cause health problems.
- Unlike tumors in other parts of the body, benign brain tumors can potentially be life-threatening.
- Benign brain tumors may become malignant.
- Contain cancer cells.
- Likely to grow rapidly.
- Often invade nearby healthy brain tissue.
- Cancer cells can break off from the main malignant brain tumor and spread to other areas of the brain.
- Cancer cells that break away and spread to the spinal cord can comprise the nervous system and cause serious health issues.
Physicians further classify brain tumors into four grades:
- Grade 1: Benign. The cells look like normal brain cells, and growth of the tumor is slow.
- Grade 2: The first stage of a malignant tumor. Cell tissue begins to look less like normal cells than in a grade 1 tumor.
- Grade 3: Malignant tissue growth becomes accelerated. The brain cells look very different than normal cells.
- Grade 4: The malignant tissue looks the most abnormal, and the growth rate is highly accelerated.
Though more common among adults than children, a low-grade tumor may become a high-grade tumor over time.
There are multiple types of primary brain tumors. Primary brain tumors are named according to which part of the brain they first form within. The most common type of brain tumor begins in the glial glands, and is called a gliorna. Other common types include Astrocytoma (arises in the cerebrum), Ependymoma (ventricles of the spinal cord), Meningioma (meninges) and Oligodendroglioma (nerve tissue).
Last updated: 5/19/2010 3:47:03 PM