Ependymomas are tumors originating from ependymal cells, which line the fluid-filled spaces of the brain and spinal cord within the central nervous system. These cells produce and regulate cerebrospinal fluid (CSF), which cushions and protects the brain and spinal cord. When these cells grow uncontrollably, they form a mass, leading to an ependymoma. These tumors can affect both children and adults.
Understanding Ependymoma Types and Grades
Ependymomas are classified into types and assigned grades based on their growth rate and cellular appearance, using the World Health Organization (WHO) grading system from Grade I to Grade III. Grade I tumors, such as subependymomas, are slow-growing and less likely to spread, often found near the brain’s ventricles.
Myxopapillary ependymomas are also classified as Grade I or II. These are slow-growing, localized tumors that originate primarily from lumbosacral nervous tissue, most commonly in young adult males. Classic ependymomas are Grade II, indicating a moderate growth rate, and can occur in children and adults throughout the brain and spinal cord.
Anaplastic ependymomas are Grade III, representing the most aggressive and fast-growing type. These tumors often develop at the base of the brain and can spread into nearby brain tissue or disseminate through the cerebrospinal fluid. Beyond these classifications, molecular subtypes are increasingly recognized for guiding diagnosis and treatment.
Ependymoma prevalence varies by age and location. In children, these tumors are often found within the brain, particularly in the fourth ventricle. In adults, ependymomas are often located in the spinal cord.
Recognizing Symptoms
Ependymoma symptoms vary significantly depending on the tumor’s location within the central nervous system. Brain tumors can cause symptoms related to increased pressure or disruption of normal brain function. Common signs include persistent headaches, nausea, and vomiting, which can result from the tumor blocking cerebrospinal fluid flow and causing hydrocephalus.
Other brain-related symptoms can include issues with balance and coordination, vision problems, or changes in personality or behavior. In children, these symptoms can be less specific or harder to identify, presenting as irritability or developmental delays. Spinal cord ependymomas often manifest with symptoms related to nerve compression.
Individuals with spinal ependymomas may experience back pain, which can radiate to other areas. Weakness or numbness in the limbs, and problems with bladder or bowel control, are also common indicators. These symptoms tend to progress as the tumor grows and puts more pressure on the spinal nerves.
Diagnosis and Underlying Factors
Diagnosing an ependymoma begins with a thorough clinical evaluation, including a neurological assessment. Imaging techniques are then employed, with magnetic resonance imaging (MRI) of the brain and spine being the primary diagnostic tool to visualize the tumor’s size, location, and extent.
A definitive diagnosis requires a biopsy, where a tissue sample is removed and examined by a pathologist. This pathological examination helps determine the specific type and grade of the ependymoma. Cerebrospinal fluid (CSF) analysis may also be performed to check for any tumor cells that have spread through the fluid.
Most ependymomas occur sporadically, with no known cause or inherited link. While rare, some genetic links have been identified, such as an association with Neurofibromatosis Type 2 in certain spinal ependymomas. These genetic predispositions account for a very small percentage of cases.
Treatment and Prognosis
Treatment for ependymomas involves a multi-modal approach, with surgery as the primary intervention. The goal of surgery is maximal safe resection, meaning the neurosurgeon aims to remove as much of the tumor as possible without damaging surrounding healthy brain or spinal cord tissue. Complete surgical removal is associated with better outcomes.
Following surgery, radiation therapy is often used, especially for higher-grade tumors or if the tumor could not be completely removed. Radiation therapy uses high-energy rays to target and destroy any remaining cancer cells. The specific dosage and area of radiation depend on the tumor’s location, grade, and the extent of surgical resection.
Chemotherapy has a more limited role in treating ependymomas compared to other central nervous system tumors. It is considered in specific situations, such as for very young children where radiation therapy is delayed, or for recurrent disease. Chemotherapy aims to kill cancer cells throughout the body using specific drugs.
The prognosis for individuals with ependymomas varies considerably. Factors influencing the outlook include the tumor’s grade, its location, the extent of surgical removal, and the molecular subtype. Lower-grade tumors and those that can be completely removed surgically have a more favorable prognosis. Given the potential for recurrence, especially with higher-grade tumors, long-term follow-up with regular imaging scans is an ongoing aspect of care.