Ependymoma is a rare central nervous system (CNS) tumor in children, and our progress in treating this disease has been hampered by its rarity as well as by a nonuniform approach to treatment among practitioners. Dr. Merchant’s comprehensive review provides a framework for plotting a course of further progress in treating children with ependymoma.
Optimal Local Control
As the author points out, optimal local control has been repeatedly shown to be the single most important prognostic factor in the treatment of this disease, and achieving this goal begins with maximal surgical resection. Failure to perform a gross total or near total resection substantially decreases the likelihood of long-term disease control.
To that end, one goal of the next Children’s Oncology Group trial is emphasis on increasing the number of patients whose tumors are gross totally or near totally resected. Second surgery is recommended for patients who undergo an initial subtotal resection. In an attempt to facilitate the second surgery, chemotherapy is administered between the first and second resections in the hopes of rendering the tumor more amenable to complete removal and, perhaps, reducing the likelihood of disease dissemination in the interim.
Following surgery, postoperative conformal radiation therapy is administered to all patients, with the exception of those with supratentorial, differentiated ependymomas whose tumors have been completely resected. Notably, and in contrast to other contemporary trials, children will receive irradiation if they are 1 year of age or older at the time of planned irradiation. Merchant argues, based on his own institutional experience, that in light of newer radiation techniques, irradiation in young children will likely result in fewer long-term neurologic sequelae than have been seen in the past, while improving long-term survival. To date, disease control in his series has been excellent, but the follow-up period is still relatively short.
Long-Term Neurologic Outcome
Aggressive attempts at local control appear to be a reasonable strategy to improve the treatment of patients with ependymoma. However, we must be careful to follow-up on the possible consequences of this approach. Although there is reason to hope that the use of more modern radiation technology and neurosurgical techniques will improve the long-term neurologic outcome of survivors, this is by no means assured.