Ependymomas are rare tumors arising from the ependyma, the membrane lining the inside of the ventricles of the brain and the central canal of the spinal cord. It follows that in the vast majority of cases, ependymomas are located intradurally in the ventricular system and in the spinal cord. Much less often, ependymomas occur outside the ventricular system, directly in the brain. A distinctive feature of these formations is that they are better demarcated from the medulla compared to most other intracerebral tumors. It follows from this that the task of the neurosurgeon is to remove the tumor as radically as possible, both in the case of intracranial localization and when the ependymoma is localized in the spinal cord. If radical removal is not possible, subsequent radiation therapy may be performed.
Ependymomas arise from ependymal cells lining the ventricles of the brain and the central canal of the spinal cord. They can be located along the entire length of the neural tube.
Frequency:
Intracranial location: constitute ≈5-6% of intracranial gliomas, 69% occur in children, accounting for 9% of pediatric brain tumors.
Spinal location: ≈60% of spinal cord gliomas, 96% of cases occur in adults, especially in the region of the filum terminale.
Average age of patients at the time of tumor diagnosis:
Intracranial localization: adults - 17 years old, children - 5 years old.
Infratentorial localization: adults - 14 years, children - 4 years.
Supratentorial localization: adults - 22 years old, children - 6 years old.
Spinal localization: 40 years.
Intramedullary localization: 47 years.
Caudal part: 32 years.
Ependymomas have the ability to spread along the neural tube along the cerebrospinal fluid tract, a process called seeding, which leads to the occurrence of “lost” metastases in 11% of cases. The incidence of metastasis increases as the tumor grade increases. In rare cases, systemic spread occurs.
Bibliography:
- Timmermann B: Die Protonentherapie. Chancen zur besseren Verträglichkeit der Tumorbestrahlung bei Kindern. Wir 2010, 1: 33 [URI: www.kinderkrebsstiftung.de] TIM2010
- Kaatsch P, Spix C: Registry - Annual Report 2008 (Jahresbericht 2008 des Deutschen Kinderkrebsregisters). Technischer Bericht, Universität Mainz 2008 [URI: www.kinderkrebsregister.de] KAA2008a
- Louis DN, Ohgaki H, Wiestler OD, Cavenee WK, Burger PC, Jouvet A, Scheithauer BW, Kleihues P: The 2007 WHO classification of tumors of the central nervous system. Acta neuropathologica 2007, 114: 97 [PMID: 17618441] LOU2007
- Kühl J, Korinthenberg R: ZNS-Tumoren. In: Gadner H, Gaedicke G, Niemeyer CH, Ritter J (Hrsg.): Pädiatrische Hämatologie und Onkologie. Springer-Verlag 2006, 777 [ISBN: 3540037020] KUE2006
- Timmermann B, Kortmann RD, Kühl J, Rutkowski S, Dieckmann K, Meisner C, Bamberg M: Role of radiotherapy in anaplastic ependymoma in children under age of 3 years: results of the prospective German brain tumor trials HIT-SKK 87 and 92. Radiotherapy and oncology 2005, 77: 278 [PMID: 16300848] TIM2005
- Gutjahr P: Tumoren des Zentralnervensystems, in: Gutjahr P (Hrsg.): Krebs bei Kindern und Jugendlichen. Deutscher Ärzte-Verlag Köln 5. Aufl. 2004, 373 [ISBN: 3769104285] GUT2004a
- Timmermann B: Therapie von Ependymomen im Kindesalter - Eine aktuelle Übersicht. WIR Informationsschrift der Aktion für krebskranke Kinder eV (Bonn) 2002, 4: 21 [URI: www.kinderkrebsstiftung.de] TIM2002a
- Kaatsch P, Rickert C, Kühl J, Schuz J, Michaelis J: Population-based epidemiologic data on brain tumors in German children. Cancer 2001, 92: 3155 [PMID: 11753995] KAA2001
- Timmermann B, Kortmann R, Kühl J, Meisner C, Bamberg M: Combined postoperative irradiation and chemotherapy for anaplastic ependymomas in childhood: results of the German prospective trials HIT 88/89 and HIT 91. Int J Radiat Oncol Biol Phys 2000, 46: 287 [PMID: 10661334]TIM2000
Ependymomas (summary in PDF format) (350KB)
Pathology
WHO classification:
1. Nonanaplastic (low grade of malignancy)
2. Papillary: “classic lesion” of the GM and SM. Metastasis is possible up to 30%.
3. Myxopapillary ependymoma: a separate form, found only in the area of the filum terminale. Papillary ependymoma with microcystic vacuoles and mucous contents.
4. Subependymoma
5. Anaplastic: pleomorphism, multinucleation, giant cells, mitoses, vascular changes, areas of necrosis (sometimes when anaplastic changes are more pronounced, the term ependymoblastoma is used, but this term should be reserved for a separate type of tumor, rare primitive neuroectodermal tumors in children). Whether the degree of anaplasia influences outcomes is unclear.
Additional Information
The text with which you have become acquainted is compiled on the basis of the modern literature, the list of which is given below. We also took into account modern therapeutic guidelines and recommendations for the treatment of children and adolescents with ependymoma, which were developed by the central research office of HIT-MED. For now, more detailed information about ependymoma can be found on our website www.kinderkrebsinfo.de in German only. If you still have questions, you can always discuss them with your attending physicians.
Intracranial ependymomas
Key Features:
1. Often occur in the bottom of the fourth ventricle
2. There is a potential threat of spread along the neural tube
3. Young patients have a worse prognosis
4. Treatment: maximum resection followed by radiation therapy.
They are usually well-circumscribed and benign tumors (although malignant ependymomas also occur). They often arise in the floor of the IV ventricle (in 60-70% of cases they are located infratentorially, always near the IV ventricle, they account for 25% of all tumors in the IV ventricle region). Posterior fossa ependymomas in children are often anaplastic and have a greater risk of spreading through the neural tube. Although histologically they do not appear as malignant as medulloblastomas, they have a worse prognosis due to the fact that they tend to grow into the obex, which prevents their complete removal. Subependymomas: they are typically located in the anterior sections of the lateral ventricles or in the posterior part of the IV ventricle, with a pronounced role of subependymal glial cells. They are often detected at autopsies and are subject to surgical treatment in rare cases.
What protocols and registries are used to treat children?
In Germany, almost all children and adolescents with ependymoma or recurrence of these types of tumors are treated according to standardized protocols called therapy optimization studies and treatment registries.
German protocols, or therapy optimization studies, are clinical studies and are strictly controlled. Their goal is to treat sick children using the most modern developments. At the same time, these studies provide an opportunity to improve treatment approaches and thereby achieve progress in treatment.
Children who are not treated according to the research protocol (for example, if at the time of illness the old protocol was closed and a new one has not yet opened; or if the form of the child’s illness does not meet the criteria described for admission to the current protocol), go through treatment registries . Treatment registries are created and operate in order to advise all patients from modern scientific positions. To ensure high quality of treatment, the research team for a particular protocol typically develops detailed therapeutic recommendations. And when attending physicians contact them, they advise them on choosing the optimal therapy for each individual child.
In Germany, at the end of 2011, the long-term protocol HIT 2000 (study of optimization of therapy for children and adolescents with ependymoma) completed its work. Numerous children's clinics throughout Germany and Austria have used this protocol. SIOP Ependymoma II protocol, is currently under development . The new protocol should begin work in 2015. Then sick children from Germany will be taken for treatment under this protocol.
Currently in Germany they work according to the following protocols and registers:
- HIT 2000 Interim Registry (abbreviated as I-HIT-MED): Children with ependymoma who are currently or in the future unable to be treated under a clinical trial protocol, or who refuse to be treated as required by a clinical trial, are enrolled in a therapeutic registry (HIT 2000 Interim Register). / register I-HIT-MED). These children receive an individual treatment plan, that is, depending on the specific form of the disease. Therefore, experts have drawn up therapeutic recommendations, based on the HIT 2000 protocol. These therapeutic recommendations can be used by all doctors in Germany. The registry is managed by the research office HIT-MED, which is located in the pediatric clinic at the University Hospital of Hamburg (the head of the research group is Prof. Dr. Stefan Rutkowski).
- HIT-REZ 2005 protocol: Another treatment optimization study is the HIT-REZ 2005 protocol (part of the E-HIT-REZ 2005 trial), which treats children with recurrent ependymoma. The central research office is located at the Center for Pediatric and Adolescent Medicine at the University Hospital Essen (headed by Prof. Dr. Gudrun Fleischhak). Please note: this protocol no longer accepts new patients as of January 1, 2013. New patients with relapse are treated according to the therapeutic recommendations developed by the central research office. These recommendations are based on the E-HIT-REZ 2005 protocol. A therapeutic registry should be opened for these children in the near future.
Diagnostics
CT/MRI:
Typically, a mass is found in the floor of the fourth ventricle, often with occlusive hydrocephalus.
Radiologically it may be difficult to differentiate from medulloblastoma, but the following signs may help:
1. Calcifications are common in ependymomas, but rare (<10%) in medulloblastomas
2. Medulloblastomas usually arise from the roof of the IV ventricle (from its apex, fastigium), which covers the tumor (“banana sign”), ependymomas tend to grow into the IV ventricle from the bottom
3. Ependymomas have a non-homogeneous structure on MRI in T1 mode
4. The exophytic component in ependymomas tends to show a high signal on T2 MRI (in medulloblastomas it is only slightly hyperintense)
Myelography
Myelography with water-soluble contrast agent has the same sensitivity for detecting metastases as MRI with gadolinium. It is also possible to do a cytological examination of the cerebrospinal fluid to determine the stage of the tumor.
The complex of symptoms inherent in the disease
The following signs of pathology are distinguished:
- severe and chronic headaches;
- dizziness;
- nausea, vomiting;
- impaired coordination of movements;
- unsteadiness of walking;
- difficulty swallowing;
- impairment of auditory and visual functions;
- epilepsy attacks;
- mental retardation (in a child);
- increased intracranial pressure;
- irritability;
- constant feeling of fatigue;
- impaired fine motor skills;
- decreased concentration.
If the tumor has involved nearby tissues, the following symptoms appear:
- sharp and severe back pain;
- gastrointestinal disorders;
- urinary incontinence.
Symptoms vary depending on the location of the tumor.
Treatment
Surgical resection
The purpose of the operation: maximum removal of the intracranial part of the tumor without neurological deficit. If there is significant tumor invasion into the bottom of the fourth ventricle, then it is completely impossible to remove it. After surgery, radiation therapy and myelography are performed to exclude possible metastasis. 10 ml of cerebrospinal fluid is sent for cytological examination to determine the number of malignant cells (if any) and can also be used as a way to monitor the effectiveness of treatment.
Radiation therapy
Ependymomas are second in radiosensitivity after medulloblastomas. Radiation therapy is prescribed after surgical removal of the tumor (survival improves after radiation therapy in the postoperative period: survival of 50% of patients was 2 years longer with radiation therapy than without it, while the number of patients who had a 5-year survival period increases from 20 -40% to 40-80%)
Prognosis after surgery
Life after treatment for ependymoma largely depends on the stage of the disease. If the disease is diagnosed in time and treated appropriately, the survival rate for more than 5 years is 70%. A less favorable prognosis is present with an anaplastic tumor, which can grow rapidly and metastasize. In this case, the chances of life are not great, and the treatment provided will prolong life by 1 - 2 years. If surgery is not possible, supportive care may increase life expectancy by just a few months.
If the operation fails to completely remove the tumor, there is always a risk of its recurrence. In such cases, the prognosis worsens, and the risk of its metastases to other organs and systems increases significantly. Unfortunately, there are no preventive measures that can protect against brain cancer. However, if you follow some rules, you can reduce tumor formation:
- proper and healthy nutrition;
- rejection of bad habits;
- eliminate the effects of radiation on the body;
- undergo regular medical examinations;
- monitor the state of the immune system.
By following basic rules, you can significantly reduce the risk of any cancer. Ependymoma is a type of brain cancer that requires timely diagnosis and quality treatment. By treating this pathology in the early stages of the disease, the chance of a positive prognosis is quite good, and the patient himself has the opportunity to return to a full life.
