In the newly diagnosed patient, careful evaluation to fully determine the extent of disease must precede the treatment of ependymoma. Surgery should be performed in an attempt at maximal tumor reduction; children have improved progression-free survival (PFS) if there is minimal residual disease present after surgery.[1,2] Postoperatively, magnetic resonance imaging (MRI) should be performed to determine the extent of resection, although the rate of dissemination is low. If not performed preoperatively, MRI of the entire neuraxis should be obtained to evaluate for disease dissemination. Myxopapillary ependymomas, considered to be a benign histologic subtype of ependymoma, have a relatively high incidence of central nervous system (CNS) tumor dissemination at diagnosis and at follow-up, and require imaging of the complete cranial spinal axis at the time of diagnosis and during follow-up.[3,4] Patients with residual tumor or disseminated disease should be considered at high risk for relapse and should be treated on protocols specifically designed for them. Those with no evidence of residual tumor still have an approximate 20% to 40% relapse risk in spite of postoperative radiation therapy.
Since you were recently diagnosed with a brain tumor, ask your doctor these questions at your next visit.
1. What type of brain tumor do I have, and what is its grade?
2. What are the symptoms of brain cancer?
3. What part of my brain is affected by the tumor and what does this region of the brain do?
4. Will it be possible to surgically remove my tumor?
5. Will I need any other treatments such as chemotherapy or radiotherapy after surgery?
6. What are the possible side effects of these therapies?
Ependymoma (World Health Organization [WHO] Grade II) and anaplastic (WHO Grade III)
No residual disease; no disseminated disease:
The traditional postsurgical treatment for these patients has been radiation therapy consisting of 54 Gy to 55.8 Gy to the tumor bed for children aged 3 years and older. It is not necessary to treat the entire CNS (whole brain and spine) because these tumors usually recur initially at the local site.[2,6,7]; [Level of evidence: 3iiiA] When possible, patients should be treated in a center experienced with the delivery of conformal radiation therapy to pediatric patients with brain tumors. There is no evidence that adjuvant chemotherapy, including the use of myeloablative chemotherapy, improves the outcome for patients with totally resected, nondisseminated ependymoma. The 3-year PFS rate in 74 patients aged between 1 and 21 years treated with radiation therapy following surgery was 77.6% ± 5.8%. In a second series of 153 patients, 107 received conformal irradiation immediately following up-front resection, the 7-year event-free survival was 76.9% ± 13.5%.[Level of evidence: 3iA] Anecdotal experience suggests that surgery alone for completely resected supratentorial nonanaplastic tumors, and intradural spinal cord ependymomas may, in select cases, be an appropriate approach to treatment.[Level of evidence: 3iiiDi]; [13,14][Level of evidence: 3iiiDiii]
Residual disease; no disseminated disease:
Second-look surgery should be considered because patients who have complete resections have better disease control. The traditional postsurgical treatment for children aged 3 years and older has been radiation therapy consisting of 54 Gy to 55.8 Gy to the tumor bed. It is not necessary to treat the entire CNS (whole brain and spine) because these tumors usually recur at the local site.[Level of evidence: 3iiiA] In subtotally resected patients, treatment with radiation therapy results in 3-year to 5-year PFS in 30% to 50% of patients,[10,16] although the outcome for patients with residual tumor within the spinal canal may be better. There is no evidence that adjuvant chemotherapy, including high-dose chemotherapy with stem cell rescue, is of any benefit.
CNS disseminated disease:
In children with disseminated disease, long-term survivors have been reported and aggressive therapy is warranted. Regardless of degree of surgical resection, these patients require radiation therapy to the entire CNS (whole brain and spine) along with boosts to local disease and bulk areas of disseminated disease. The traditional local postsurgical radiation doses in these patients have been 54 Gy to 55.8 Gy. Doses of approximately 36 Gy to the entire neuraxis (i.e., the whole brain and spine) should also be administered, but may be modulated depending on the age of the patient. Boosts between 41.4 Gy and 50.4 Gy to bulk areas of spinal disease should be administered, with doses depending on the age of the patient and the location of the tumor. When possible, patients should be treated in a center experienced with this therapy. Trials are ongoing to evaluate the possible role of radiation therapy and chemotherapy in these patients.
Management of children younger than 3 years:
Because of the known effects of radiation on growth and neurocognitive development, radiation therapy immediately after surgery in children younger than 3 years has traditionally been limited, with attempts to delay its administration through the use of chemotherapy.[19,20,21,22]; [Level of evidence: 2A] When analyzing neurologic outcome following treatment of young children with ependymoma, it is important to consider that not all long-term deficits can be ascribed to radiation therapy, as deficits may be present in young children before therapy is begun. For example, the presence of hydrocephalus at diagnosis is associated with lower intelligence quotient as measured following surgical resection and prior to administration of radiation therapy.
In a retrospective review based on Surveillance Epidemiology and End Results data of 184 children younger than 3 years, 3-year overall survival was shown to be significantly better for children who received postoperative radiation therapy (81%) than for those who did not (58%, P = .005), even when adjusting for tumor location or degree of resection. The recently completed Children's Oncology Group protocol for children with ependymoma included children aged 1 year and older. The trial is a prospective evaluation of this same issue and results are forthcoming.
Conformal radiation therapy is an alternative approach for minimizing radiation-induced neurologic damage in young children with ependymoma. The initial experience with this approach suggests that children younger than 3 years with ependymoma have neurologic deficits at diagnosis that improve with time following conformal radiation treatment. However, another study suggested that there was a trend for intellectual deterioration over time even in older children treated with localized radiation therapy.[Level of evidence: 3iiiC] The need and timing of radiation therapy for children who have successfully completed chemotherapy and have no residual disease is still to be determined.
Chemotherapy is able to induce objective responses in some children younger than 3 years with newly diagnosed ependymoma,[19,20,21] although not all chemotherapy regimens induce objective responses. Up to 40% of infants and young children with totally resected disease may achieve long-term survival with chemotherapy alone.[Level of evidence: 2Di]