Ependymoma Malignant

Malignant ependymoma is a fast-growing tumor that forms in the brain or spinal cord, arising from specialized cells that line fluid-filled spaces in the central nervous system. While these tumors can affect people at any age, understanding their characteristics, symptoms, and treatment options is essential for managing this serious condition.

Table of contents

• What Is Malignant Ependymoma?
• Where Malignant Ependymomas Form
• Types and Grades
• Signs and Symptoms
• Causes and Risk Factors
• How It Is Diagnosed
• Treatment Options
• How Malignant Ependymomas Spread
• Outlook and Prognosis

What Is Malignant Ependymoma?

Malignant ependymoma is a type of tumor that develops in the central nervous system, which includes the brain and spinal cord. These tumors begin in ependymal cells, which are specialized cells that line the passageways carrying cerebrospinal fluid. This fluid surrounds and protects the brain and spinal cord^[1].

Ependymomas are considered primary tumors, meaning they form directly in the brain or spinal cord rather than spreading from somewhere else in the body^[3]. When the tumor grows quickly and invades nearby tissue, it is called malignant or cancerous. These fast-growing tumors can break away and spread within the brain or spinal cord^[1].

• Brain
• Spinal cord
• Ventricles (fluid-filled spaces in the brain)
• Cerebellum
• Brainstem

Where Malignant Ependymomas Form

Malignant ependymomas can form anywhere in the central nervous system. They often occur near the ventricles in the brain and the central canal of the spinal cord^[2]. The ventricles are open spaces in the brain that contain cerebrospinal fluid.

In children, most ependymomas occur near or in the cerebellum and spinal cord. In adults, these tumors are more commonly found in the spine^[5]. The location of the tumor affects what symptoms a person experiences and how doctors approach treatment.

When ependymomas occur in the brain, they are typically described as arising in either the supratentorial or infratentorial region. The supratentorial region makes up the upper two-thirds of the brain, including the cerebrum. The infratentorial region makes up the lower third of the brain, including the brainstem and cerebellum^[6].

Types and Grades

Healthcare providers grade ependymomas on a scale from 1 to 3 based on how quickly they grow and how abnormal the cells look under a microscope. Grade 3 ependymomas are malignant, meaning they are cancerous and fast-growing^[2].

Grade 1 ependymomas are slow-growing tumors that are often considered benign. Grade 2 ependymomas are also low-grade tumors, but they are more likely to return after treatment than grade 1 tumors, especially if they cannot be completely removed during surgery^[2].

Grade 3 ependymomas, also called anaplastic ependymomas, are the fastest-growing type. They occur most often in the brain but can also occur in the spine. These tumors tend to spread to other parts of the brain or spinal cord and are more likely to return after treatment^[2][3].

The location and specific changes in the genes of each ependymoma can predict how well treatment will work better than grade alone. According to the 2021 World Health Organization classification, there are several molecular subtypes of ependymoma based on genetic features and location in the brain or spine^[2].

Signs and Symptoms

The symptoms of malignant ependymoma depend on where the tumor is located in the brain or spinal cord. A tumor can cause problems by pressing on nearby structures or blocking the normal flow of cerebrospinal fluid^[1].

People with a malignant ependymoma in the brain may experience headaches, nausea, vomiting, blurry vision, confusion, irritability, and seizures^[1][2]. Babies and very young children who cannot describe their symptoms may show a larger-than-usual head, unusual sleeplessness, excessive fussiness, or more vomiting than usual^[3].

If a malignant ependymoma is located in the spinal cord, symptoms can include back pain, neck pain, numbness and weakness in the arms or legs, problems with balance and walking, and difficulty controlling the bladder or bowels^[1][2].

Causes and Risk Factors

The exact cause of malignant ependymomas is not known. These tumors may happen when ependymal cells in the brain or spinal cord divide and grow in an abnormal way^[3].

Ependymomas can occur in people with certain inherited conditions. Some studies suggest that people with neurofibromatosis type 2, a genetic disease, may be more likely to develop ependymomas, though experts are still studying this connection^[2][3].

Malignant ependymomas can affect people at any age, but they occur most often in young children. Ependymomas are the third most common type of brain tumor in children^[4]. In adults, ependymomas are often diagnosed in people in their 30s or 40s^[4].

How It Is Diagnosed

Doctors diagnose malignant ependymoma using several tests and procedures. The diagnostic process begins with learning about a patient’s medical history and symptoms, followed by a physical examination and a neurological exam. During the neurological exam, a healthcare professional checks vision, hearing, balance, coordination, strength, and reflexes^[14].

Imaging tests are essential for diagnosing ependymomas. An MRI (magnetic resonance imaging) scan is the most commonly used imaging test. It creates detailed pictures of the brain or spinal cord and can show the location and size of the tumor. Doctors may use specialized MRI techniques or add a contrast material to make the tumor more visible^[14].

A CT scan (computed tomography) may also be used to create images of the brain or spinal cord. Because ependymomas can occur in both the brain and the spinal cord, imaging tests may be performed on both areas^[4].

A lumbar puncture, also called a spinal tap, involves inserting a needle between two bones in the lower spine to remove cerebrospinal fluid. The fluid is tested to look for tumor cells^[14].

To confirm the diagnosis, doctors need to examine tumor tissue under a microscope. This is done through a biopsy, where a small amount of tumor tissue is removed for testing. In many cases, doctors remove as much of the tumor as possible during surgery and then test the tissue to determine the exact type and grade of ependymoma^[4][14].

Treatment Options

Surgery is the primary treatment for malignant ependymoma. A brain surgeon, called a neurosurgeon, works to remove as much of the tumor as possible. The goal is to remove the entire tumor if it can be done safely. Sometimes the tumor is located near sensitive brain or spinal tissue, making complete removal too risky^[14].

The extent of tumor removal during surgery is the most important factor affecting long-term survival for patients with ependymoma. Complete removal, called gross total resection, provides the best outcomes^[18].

Radiation therapy is commonly used after surgery for malignant ependymomas. This treatment uses powerful X-rays or other types of radiation to destroy tumor cells. Radiation may be given to the area where the tumor was located or, if the tumor has spread through cerebrospinal fluid, to the whole brain and spinal cord^[14][17].

Several methods can deliver radiation treatment. Conformal radiotherapy and intensity-modulated radiotherapy are computer-assisted techniques that are more precise. Proton beam radiotherapy may provide additional protection to normal structures. Stereotactic radiosurgery delivers precisely focused, high-dose radiation beams to a small area and is administered over one to three days^[17].

Chemotherapy uses drugs to kill cancer cells. For malignant ependymomas, chemotherapy is usually only needed if the tumor has spread to other areas of the body, which is very rare. Chemotherapy may also be used in addition to radiation for some aggressive tumors^[3][17].

Currently, there are no ependymoma-specific treatments that target molecular features of the tumor, but this is an active area of research^[18].

How Malignant Ependymomas Spread

Malignant ependymomas rarely spread outside the central nervous system. However, they can spread to other areas of the brain or spinal cord through cerebrospinal fluid^[2][7].

About 10 to 15 percent of ependymomas move to other locations in the central nervous system via the cerebrospinal fluid. It is very rare for an ependymoma to spread outside the central nervous system to other parts of the body^[6].

Because of the possibility of spread within the central nervous system, doctors often examine cerebrospinal fluid during diagnosis and may perform imaging tests of both the brain and spine, even if symptoms suggest the tumor is in only one location^[14].

Outlook and Prognosis

The outlook for people with malignant ependymoma depends on several factors, including the location of the tumor, how much of the tumor can be removed during surgery, the patient’s age, and specific features of the tumor cells^[18].

Grade 3 malignant ependymomas are fast-growing and more likely to return after treatment compared to lower-grade tumors. They tend to spread into nearby parts of the brain and can spread to other parts of the central nervous system through cerebrospinal fluid^[6].

Complete surgical removal of the tumor provides the best chance for long-term survival. When complete removal is not possible, additional treatments such as radiation therapy are important for controlling the disease^[18].

Because ependymomas can return even after successful treatment, patients typically need regular MRI surveillance to monitor for recurrence. Follow-up care and monitoring are essential parts of managing this condition over time^[18].