Stages of Childhood Brain Stem Glioma
Key Points for This Section
- The plan for cancer treatment depends on whether the tumor is in one area of the brain or has spread throughout the brain.
- There are three ways that cancer spreads in the body.
- The information from tests and procedures done to detect (find) childhood brain stem glioma is used to plan cancer treatment.
There is no standard staging system for childhood brain stem glioma. Instead, the plan for cancer treatment depends on whether the tumor is diffuse (spread throughout the brain) or focal (in one area of the brain):
- Diffuse intrinsic pontine glioma is a tumor that has spread widely throughout the brain stem. A biopsy is usually not done for this type of brain stem glioma and it is not removed by surgery. A diffuse intrinsic pontine glioma is usually diagnosed using imaging studies.
- Focal or low-grade glioma is a tumor that is in one area of the brain stem. A biopsy may be done and the tumor removed during the same surgery.
The three ways that cancer spreads in the body are:
- Through tissue. Cancer invades the surrounding normal tissue.
- Through the lymph system. Cancer invades the lymph system and travels through the lymph vessels to other places in the body.
- Through the blood. Cancer invades the veins and capillaries and travels through the blood to other places in the body.
When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
Some of the tests used to detect childhood brain stem glioma are repeated if the tumor is removed by surgery. (See the General Information section.) This is to find out how much tumor remains after surgery and plan further treatment.