Medulloblastoma - Childhood: Stages

Approved by the Cancer.Net Editorial Board, 05/2014

ON THIS PAGE: You will learn about how doctors describe a tumor’s growth or spread. This is called the stage. To see other pages, use the menu on the side of your screen.

Staging is a way of describing the size of a tumor, where it is located, if it is cancerous or where it has spread, and whether it is affecting other parts of the body. Doctors use diagnostic tests to find out the tumor’s stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient’s prognosis, which is the chance of recovery. There are different stage descriptions for different types of tumors.

Medulloblastoma in children is classified as either standard (average) risk or high risk, depending on the following factors: the child’s age, how much of the tumor remains after surgery, and whether the tumor has spread.

Standard-risk tumor. The tumor is in the very back part of the brain and has not spread to other areas of the brain and spinal cord. Additionally, it is almost completely removed during surgery, meaning that less than 1.5 cubic centimeters (cm) of the tumor remains after surgery. However, the surgeon will usually prefer to remove all of the tumor if it can be completely removed without increasing the risk of severe side effects.

High-risk tumor. This type of tumor has either spread to other parts of the brain or the spine, or it has not spread but more than 1.5 cubic cm of tumor remains after surgery. Some tumors that first appear to be standard-risk tumors have high-risk molecular features and are treated as high-risk tumors.

Recurrent tumor. A recurrent tumor is a tumor that has come back after treatment. It may recur in the brain, spine, spinal fluid or, very rarely, elsewhere in the body. If there is a recurrence, the tumor may need to be staged again (called re-staging) using the system above.

Information about the tumor’s stage will help the doctor recommend a treatment plan. The next section helps explain the treatment options for medulloblastoma. Use the menu on the side of your screen to select Treatment Options, or you can select another section, to continue reading this guide.