​Epidemiology:
May occur anywhere in the CNS. 3rd most common CNS tumor in children. Male and female have equal incidence rates. Most common in children under 4 years old.7
Etiology:
Ependymomas have no known environmental cause. A number of genetic mutations have been associated with ependymomas. Intramedullary ependymomas have been associated with neurofibromatosis type I.2
Signs & Symptoms:
Focal neurologic dysfunction, increased intracranial pressure, hydrocephalus. The neurologic effects of the locally growing or infiltrating tumor may predict the tumor location. Headache usually worse in the morning due to intracranial pressure. Optic atrophy or blindness. Seizures, back pain, bowel or bladder dysfunction.1 A history of progressive lethargy, headache, nausea, and vomiting may be experienced with increased intracranial pressure from obstructive hydrocephalus. For those children who present prior to closure of cranial sutures, enlarging head circumference secondary to obstructive hydrocephalus also may be part of the clinical history. Changes in personality, mood, and concentration can be early indicators or may be the only abnormalities observed. Seizures in 20% of patients, and focal neurologic deficits may also be prominent.2
Diagnostic Procedures:
CT, MRI, and PET scan, complete blood count, cerebral spinal fluid chemistry tests, cytology and microbiology studies. Neurologic exam includes mental condition, coordination, sensation, reflexes and motor tests.1
Histology:
Ependymomas are derived from the ependymal cells lining the ventricular system and occur throughout the central nervous system.1
Lymph Node Drainage:
According to the AJCC, the reason that the N in the TNM staging doesn’t work for brain and spinal cord cancers is because the brain and spinal cord do not have lymph nodes.8
Metastatic Spread:
“An M classification is not pertinent to the majority of neoplasms that affect the central nervous system, because most patients with tumors of the central nervous system do not live long enough to develop metastatic disease (except for some pediatric tumors that tend to “seed” through the cerebrospinal fluid spaces)." This phenomenon of “seeding” is rarely seen adults and is a hallmark for some childhood tumors. The M category of the TNM staging should help “differentiate between extraneural metastasis and metastasis within CNS and CSF pathways.”8
Ependymomas will seed in the CNS and CSF pathways.9
Grading:
The World Health Organization (WHO) classification scheme for these tumors includes 4 divisions based on histologic appearance.
WHO Grade I: myxopapillary ependymoma and subependymoma
WHO Grade II: ependymoma (with cellular, papillary, and clear cell variants)
WHO Grade III: anaplasic ependymoma.
2
Staging:
No conventional staging criteria exist for intracranial or spinal ependymomas. Postoperative MRI is recommended within 48 hours of tumor resection to assess presence of residual tumor and to facilitate adjuvant treatment planning. In the case of children with ependymomas of the fourth ventricle, a surveilance spinal MRI is often recommended to rule out seeding.2
Radiation Side Effects:
The following side effects are possible with irradiation to the brain in children. The presence of these side effects varies due to tumor location, tumor size, and treatment technique/total dose. Late radiation side effects tend to be worse the younger a child is during treatment.5

-Fatigue, skin irritation (on scalp) and neurologic deterioration can all occur during and shortly after the course of radiation treatment.5
-Hormone deficiency (growth hormone, thyroid-stimulating hormone, adrenocorticotropic hormone, and gonadotropins) can occur when the pituitary and hypothalamus receive a dose of 20 Gy or more.1,5
-Hair loss (temporary or permanent) can occur with doses of 20-40 Gy and doses greater than 40 Gy, respectively.5
-Optic neuropathy and brain necrosis can occur with doses over 60 Gy.1
-Secondary malignancies in the bone, soft tissue or bone marrow can occur later in life.1,5
-Late effects from high dose hyperfractionated regimens include: neurocognitive deficits, hearing loss, leukoencephalopathy, diffuese microhemorrhages, and dystrophic calcifications.1
Prognosis:
Overall survival is approximately 55%.
Age and extent of tumor resection are major prognostic factors.

5 year survival rate: Infants < 1 year: 25%
Children 1-4 yrs: 46%
Children > 5 yrs: > 70%

For patients with a complete tumor resection, survival rates are 60-80% following radiation treatment have been reported. For patient's with a partial tumor resection, survival rates drop to less than 30%.
3
Treatments:
General Management
  • Maximal surgical resection is the optimal intial therapy, although it possibly should be delayed in infants in whom response to initial chemotherapy may permit more complete "secondary" resection.
  • For supratentorial tumors, size and location may limit resectability.
  • Radiation therapy adds to disease control and survival. Two retrospective studies found the survival to be 0% and 13% with surgery alone compared with 45% and 59% with radiation.
  • Ependymomas are relatively sensitive to chemotherapy, especially alkylating agents and platinum compounds.

Radiation Therapy
  • Debate continues regarding the appropriate irradiation volume for intracranial ependymomas.
  • Disease contral rates in contemporary series show no advantage to full cranial or craniospinal volumes compared with wide local fields, based on modern imaging.
  • The standard local volume for posterior fossa ependymomas encompasses the entire posterior fossa, the inferior border is typically at the C2-3 interface.
  • For tumors extending into the upper cervical spine, the inferior margin should be two vertebral levels below the preoperative tumor extent until field reduction at 45 Gy.
  • Based on the recognized failure pattern at sites of identified invasion or residual disease, there now is greater acceptance of more localized treatment volumes.
  • For supratentorial ependymomas, wide local fields are defined by preoperative tumor extent, accounting for shifts in the normal brain postoperatively; margins of 2 to 3 cm are recommended.
  • For intraventricular extension, full ventricular irradiation (45 Gy) is appropriate.
  • Current guidelines call for 50 to 55 Gy to the primary tumor site, including field reduction at 45 Gy to more narrowly encompass the tumor bed.
  • Boost doses to 55-65 Gy have been recommended and are directed to small volumes of known residual disease, preferably using stereotactic radiosurgery or fractionated stereotactic irradiation.1
TD5/5:
The following organs have the potential of being in the treatment field depending on tumor size and location.

Brain: 45Gy (whole), 50Gy (2/3), 60Gy (1/3)
Brainstem (large tumors): 50Gy (whole), 53Gy (2/3), 60Gy (1/3)
Cauda equina: 60 Gy
Ear (acute serous otitis): 30Gy
Ear (chronic serous otitis): 55Gy
Lens: 10 Gy
Optic Chiasm: 50 Gy
Optic Nerve: 50 Gy
Retina: 45 Gy
Spinal Cord: 44 Gy (20cm), 50 Gy (10cm), 50 Gy (5cm)
4
Planning Photos
Treatment planning images showing the isodose distribution of 6 field IMRT plan to posterior fossa.6

EpendyCoronalView.jpg
Transverse view


EpendyTransverseView.jpg
Coronal view


EpendySagView.jpg
Sagittal view

References
1. Chao KS, Perez CA, Brady LW. Radiation Oncology - Management Decisions. 2nd ed. Philadelphia: Lippincott, Williams & Wilkins, 2002: 623-639.
2. eMedicine. Ependymoma. http://emedicine.medscape.com/article/277621-overview. Accessed February 4, 2010.
3. eMedicine. Ependymoma. http://emedicine.medscape.com/article/986333-overview . Accessed February 10, 2010.
4. Radiation Oncology/Toxicity/Emami. http://en.wikibooks.org/wiki/Radiation_Oncology/Toxicity/Emami. Accessed February 10, 2010.
5. Washington CM, Leaver D.
Principles and Practice of Radiation Therapy. 2nd ed. Philadelphia, PA: Mosby, Inc; 2004:736-7, 880-1.
6. Digitally Reconstructed Radiographs courtesy of Ginnie Dea, RT(T), Alta Bates Summit Comprehensive Cancer Center.
7. Gunderson and Tepper. Clinical Radiation Oncology. 2nd Edition. Philadelphia, PA: Churchill Livingstone. 2007.
8. Greene et al. Cancer Staging Handbook. 6th Edition. Chicago, Illinois: Eli Lilly and Company. 2001.
9. Khan. Treatment Planning in Radiation Oncology. 2nd Edition. Philadelphia, PA: Lippincott Williams and Wilkins. 2007.


Ginnie is
bright blue.
Bridget is
dark green.
Sheri is
brown.
Zack is
purple.
Matthias is
red.