Intramedullary Spinal Cord Tumors in Children Homepage

Author

Rick Abbott, M.D.

Section Editors

Kristian Aquilina, M.D.

Editor in Chief

Rick Abbott, M.D.

Introduction

IMSCTs are rare, occurring in approximately 160-200 children in North America every year. While there is no age predilection, they may occur in slightly more males than females. There are no environmental risk factors for developing a spinal cord tumor.

In children the most common type of IMSCT is the astrocytoma (approximately 40%), followed by gangliogliomas and other glial-neuronal tumors (35%), ependymomas (10–15%), hemangioblastomas (2-10%), and cavernous hemangiomas (1%). Most of these tumors are benign (70-93%) and their slow growth results in a gradual development of symptoms. Consequently, it is not uncommon for there to be a delay in diagnosis.  The most frequent presenting complaint is motor regression, observed in about 65% of patients, followed by pain (948%), dysesthesia (32%), kyphoscoliosis (32%), and bowel or bladder dysfunction (32%).

MRI, with and without gadolinium enhancement, is the imaging of choice and its findings are typically diagnostic. Astrocytomas and gangliogliomas arise eccentrically within the cord, while ependymomas arise centrally from the ependymal cells lining the central canal—this distinction is near- universal and can be used for surgical planning. The asymmetry in tumor location and growth seen with the more common astrocytoma or ganglioglioma tumors gives rise to the typical asymmetrical motor findings, increased tone, and hyperreflexia (myelopathy). Sensory deficits and proprioceptive loss may also be present.

The development of new surgical tools and the means to monitor the cord’s tolerance of surgery have dramatically decreased the risks associated with spinal cord surgery. Surgical resection is now the preferred initial treatment for IMSCTs. A key finding from the landmark Constantini and Epstein series of 164 children is that an 80% or greater resection yields the same 5-year event-free survival (approximately 70%) as a gross total resection.(10)  This survival rate also is comparable to that seen in children treated with conservative surgery followed by irradiation, but surgery with 80%+ resection of the tumor avoids the long-term risks associated with irradiating a growing spine are avoided.

Complications occur in about 9% of children undergoing surgery for their IMSCT,experience complications with the most common being sensory dysesthesias (60%), and urinary dysfunction (40%). 24% have a functional decline as measured by the McCormick Scale, and 18% develop hydrocephalus that requires treatment.

In general, long-term outcomes are good. When an 80% resection of an IMSCT is accomplished, the 5-year overall survival is approximately 88% and the event-free survival is 70%. Those within the treatment failure group who were reoperated on experienced the same incidence of complications as seen in the study group at their first operation.

Key  Points

• Surgery same as radiation: The incidence of complications after surgery equals that seen when IMSCTs are treated with radiation.
• Timing of surgery: Treatment is better tolerated when a patient’s function is only minimally degraded.
• Amount of resection: Radical resection is better tolerated than a biopsy.
• Management of recurrence: The risks of re-operation for tumor recurrence or progression are the same as those of a first-time operation and occur with a similar frequency.