Stages and Grades of Childhood Ependymoma

Executive Summary

The staging system of childhood ependymoma helps determine the tumor’s location and its metastasis. The staging system of childhood ependymoma uses diagnostic tests. A TNM staging system is used to identify the different stages of tumor. No standard staging system is available for childhood ependymoma. Therefore, the tumor is classified based on its location in the brain and which parts it has metastasized or spread. Supratentorial, Infratentorial, Spinal and recurrent are the classification of childhood ependymoma tumors. Childhood ependymoma is also described based on their grade. The grade of Ependymoma tumor explains to what extent the tumor cells look like or resemble normal, healthy cells when viewed under a microscope. World Health Organization classifies ependymoma brain tumors into three grades: Grade I to be sub-ependymoma, Grade II to be ependymoma or myxopapillary ependymoma, and Grade III to be anaplastic ependymoma. The lower the tumor grade, the better the disease prognosis.

Stages and Grades of Childhood Ependymoma

Staging is a way of describing a disease condition in terms of its gravity and location. If a person is diagnosed with a tumor, the doctor will use various diagnostic tests to determine the ependymoma stages. Knowing the stage will help the healthcare team to understand how advanced the disease condition is and what treatment plan can be employed to treat the condition. Staging can be vital in determining a patient’s survival rate once being diagnosed with the disease condition.

In the case of tumors or cancerous growth, doctors usually use a TNM staging system to find the stages of ependymoma. In the TNM staging system, T stands for tumor, N stands for nodes, and M stands for metastasis.

T (Tumor): The staging system will look for the size of the tumor, how big it is and its location of origin. 

N (Node): In terms of node, it checks whether the tumor has spread to the surrounding lymph nodes or not. If so, where and how many have been affected?

Metastasis (M): whether the cancerous growth has metastasized or spread to different parts of the body. If so, which all body parts have been affected and to what extent? 

These results are combined to determine a person’s cancer or Ependymoma stages.

For ependymoma brain tumors, there is no formal staging system available. But the tumor can be classified based on its location in the brain and which parts it has metastasized or spread. Following are the tumor classifications:

• Supratentorial: the tumor is located above the membrane covering the cerebellum known as tentorium cerebella.
• Infratentorial: the tumor location is below the membrane cover tentorium cerebella.
• Spinal: the tumor is located in the areas of the spine. They may be found in the central canal or at the bottom part of the spinal cord.
• Recurrent: a recurrent tumor refers to a tumor growth that returns to the body after treatment. If a tumor recurs in the body, another round of diagnostic tests and evaluations would be required to study the extent of the recurrence. The tests and scans conducted are often similar to those during initial disease diagnosis and treatment.

Ependymoma Tumour Grade

Ependymoma brain tumors can also be described by their grade ^​1​. The grade of Ependymoma tumor explains to what extent the tumor cells look like or resemble normal, healthy cells when viewed under a microscope. The doctor will compare the normal healthy tissue with the tumor tissue. Healthy tissue will contain many different types of cells, all grouped. A tumor is called a low-grade or differentiated tumor if it resembles healthy cells but has different cell groupings. If the cell grouping is entirely different, the tumor type is called a high-grade or poorly differentiated tumor. 

WHO or World Health Organization classifies ependymoma brain tumors into three grades ^​2​:

• Grade I (1): Sub-ependymoma
• Grade II (2): Ependymoma or myxopapillary ependymoma
• Grade III (3): Anaplastic ependymoma

In general, the lower the tumor grade, the better the disease prognosis. But there are several opinions among researchers and doctors about the vitality of grade in determining the disease prognosis of children diagnosed with “classic” ependymoma (WHO grade II) and “anaplastic ependymoma” (WHO grade III). 

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