Intradural Extramedullary Ependymoma with Leptomeningeal Dissemination: The First Case Report in a Child and Literature Review Mariasavina Severino1, Alessandro Consales2, Matteo Doglio3, Domenico Tortora1, Giovanni Morana1, Salvina Barra5, Paolo Nozza4, Maria Luisa Garre`3
Key words Children - Intradural extramedullary ependymoma - Magnetic resonance imaging - Radiotherapy - Surgery -
Abbreviations and Acronyms MRI: Magnetic resonance imaging WHO: World Health Organization From the 1Neuroradiology Unit, 2Neurosurgery Unit, 3 Neuroncology Unit, 4Pathology Unit, Istituto Giannina Gaslini; 5Department of Radiation Oncology, IRCCS San Martino IST, Genoa, Italy To whom correspondence should be addressed: Mariasavina Severino, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2015) 84, 3:865.e13-865.e19. http://dx.doi.org/10.1016/j.wneu.2015.04.002 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2015 Elsevier Inc. All rights reserved.
Primary intradural extramedullary ependymomas are very rare tumors and have never been described in children.
DESCRIPTION: We report on an 11-year-old girl presenting with a 1-month history of neck pain, left arm weakness, paresthesia in the fingers of the left hand and gait disturbances. Magnetic resonance imaging on admission revealed an intradural extramedullary cystic lesion at the cervical level with craniospinal leptomeningeal nodules causing mild hydrocephalus. The multicystic lesion was surgically removed and neuropathologic examination revealed a World Health Organization grade II ependymoma. The patient underwent adjuvant radiotherapy with progressive reduction of the metastatic nodules. At her 2-year follow-up, the patient was symptom free with no evidence of recurrence on magnetic resonance imaging.
Although a rare entity, intradural extramedullary ependymomas should be included in the differential diagnosis of intradural extramedullary lesions in children. Surgical treatment seems to play a pivotal role in the prognosis of these rare tumors, with a possible role for adjunctive radiotherapy in the case of recurrence, anaplastic transformation, and metastasis.
INTRODUCTION Primary spinal cord tumors are very rare in the pediatric age group with an overall incidence rate of 0.26 per 100,000 personyears (24). Ependymomas are the third most frequent tumor of the central nervous system in children and adolescents, after astrocytic tumors and embryonal tumors (23). However, only 13% of pediatric ependymomas are located in the spinal cord and they are uncommon outside the setting of neuroﬁbromatosis type 2 (23). Excluding myxopapillary ependymomas, which almost exclusively arise from the ﬁlum terminale, spinal ependymomas are usually intramedullary and most commonly encountered in the cervical and thoracic cord (26). Primary intradural extramedullary ependymomas are very rare. Only 24 cases have been described in the literature, all involving adult patients (1-7, 9-16, 18, 20-22, 25, 27-30). Here, we report the ﬁrst pediatric case of primary diffuse intradural extramedullary
ependymoma with extensive leptomeningeal dissemination and we review the literature on this rare tumor entity. CASE REPORT History and Examination An 11-year-old girl presented with a 1month history of progressive neck pain and stiffness, left arm weakness, paresthesia in the left hand ﬁngers, and gait disturbances. On examination, the patient had severe neck pain and stiffness, left arm weakness, and hypotrophy. Walking on heels and toes was possible with some difﬁculties. No urinary problems or bowel dysfunction were reported. Cranial nerve functions were normal. There was no cutaneous stigmata or family history of neuroﬁbromatosis type I. The results of a polysomnographic study, somato-sensitive evoked potentials, auditory brainstem responses, and the results of a urological evaluation were normal. Hormonal
WORLD NEUROSURGERY 84 : 865.e13-865.e19, SEPTEMBER 2015
assessment demonstrated normal sexual maturation. Craniospinal magnetic resonance imaging (MRI) demonstrated a multicystic lesion within the cervical canal, extending from the craniocervical junction to C4-C5 (Figure 1). The lesion was located laterally in the spinal canal, compressing and displacing the spinal cord. These ﬁndings suggested extramedullary localization of the lesion. The cystic content was essentially isointense with the cerebrospinal ﬂuid on all pulse sequences. Multiple enhancing nodules, hypointense on T2-weighted images, encased the main cystic lesion and disseminated along the surface of the spinal cord, cauda equina, brainstem, and basal cisterns. Mild ventricular dilatation due to subarachnoid space obstruction was present with initial signs of transependymal cerebrospinal ﬂuid resorption. At this time, we reviewed a brain MRI without gadolinium injection performed
CASE REPORT MARIASAVINA SEVERINO ET AL.
DISSEMINATED INTRADURAL EXTRAMEDULLARY EPENDYMOMA
attachment to the pia was noted. The intraoperative pathologic examination revealed an ependymal tumor. Gross total resection of the primary lesion was achieved and partial removal of the secondary leptomeningeal nodules was performed without damage to the spinal cord (Figure 3D). A few days later, a postoperative head computed tomography scan revealed worsening of the communicating hydrocephalus and a ventriculoperitoneal shunt was performed.
Figure 1. Craniospinal magnetic resonance imaging at presentation. Sagittal T2-weighted (A) and contrast-enhanced T1-weighted (B) images reveal a multicystic lesion with enhancing internal septa, extending from the craniocervical junction to C4-C5 (arrowheads) and multiple enhancing solid nodules disseminated along the surface of the spinal cord and cauda equina. Coronal (C) and axial (D) T2-weighted images demonstrate the extramedullary lateral localization of the cystic lesion (arrowheads). The spinal cord is displaced and compressed by the cystic lesion (white arrows). Note the mild ventricular dilatation. (E) Axial fluid attenuation inversion recovery images show nodular intracranial dissemination.
2 years before in another hospital for a trivial head trauma, and we noticed small intradural extramedullary lesions at the cervical level (Figure 2), thereby ruling out the possibility that the tumor could be a primitive intramedullary exophytic lesion. Operation A suboccipital craniectomy and a C1-C4 laminotomy were performed at the site of the major compression of the spinal cord according to the MRI ﬁndings. Neurophysiologic monitoring was used during the
surgical procedure, with somatosensory and brainstem auditory evoked potentials. When the dura was opened, multiple graybluish soft nodules were observed along the surface of the spinal cord, obliterating the spinal canal and encasing the rootlets (Figure 3A). After partial resection of these nodules, a soft gray-bluish extramedullary tumor was noted (Figure 3B, C). The spinal cord was compressed and displaced to the right. Under microscopic assistance, no attachment of the tumor to the dura or spinal cord was observed. Microvascular
Pathologic Findings Neuropathologic examination demonstrated a tumor whose key architectural feature was the presence of many perivascular pseudorosettes (Figure 4). True ependymal rosettes and canals were also found. Some samples have the hallmarks of a cyst wall with a smooth (outer) surface consisting of a layer of reticular ﬁbers (Figure 4C). The degree of nuclear density was moderate with inconspicuous hypercellular areas. The nuclei of the neoplastic cells were mainly oval with salt and pepper speckling of the chromatin. The cytoplasm was mainly mildly eosinophilic but some was clear with a distinct cytoplasmatic border. Mycrocystic areas were found. Neither vascular proliferation nor necrosis was seen. The mitotic index was extremely low (
Intradural Extramedullary Ependymoma with Leptomeningeal Dissemination: The First Case Report in a Child and Literature Review.
Primary intradural extramedullary ependymomas are very rare tumors and have never been described in children...