Extra-axial central nervous system lesions can occasionally involve the overlying calvarium. The involvement may be due to longstanding pressure effects or secondary to the aggressive behaviour of the lesion. The spectrum of such dural-based lesions varies from infectious/inflammatory to neoplastic etiology. We present a dural-based lesion with the erosion of the overlying calvarium in a young lady. In view of the short history with heterogenous enhancement on magnetic resonance imaging and bony erosion, hemangiopericytoma or malignant meningioma was suspected. The histopathology, however, proved it to be an anaplastic (grade III) ependymoma. Extra-axial ependymomas though uncommon have been reported. However, these extra-axial ependymomas presenting with calvarial erosion are unknown. The bony erosion, as in the present case, may suggest an aggressive tumour behaviour. The reported extra-axial supratentorial ependymomas along with their salient radiological/operative features are shortly reviewed. Also, the differentials of extra-axial lesions with calvarial involvement are touched upon.

Keywords:
Supratentorial ependymoma, Extra-axial ependymoma, Anaplastic ependymoma, Ependymoma, Meningioma
1.
Smith AB, Horkanyne-Szakaly I, Schroeder JW, Rushing EJ: From the radiologic pathology archives: mass lesions of the dura: beyond meningioma-radiologic-pathologic correlation. Radiographics 2014;34:295-312.
2.
Salunke PS, Gupta K, Malik V, Kumar N, Henke LE, Cai C, et al: Primary Ewing's sarcoma of cranial bones: analysis of ten patients. Acta Neurochir (Wien) 2011;153:1477-1485.
3.
El Asri AC, Akhaddar A, Baallal H, Boulahroud O, Mandour C, Chahdi H, et al: Primary lymphoma of the cranial vault: case report and a systematic review of the literature. Acta Neurochir (Wien) 2012;154:257-265; discussion 265.
4.
Yang Y, Tian KB, Hao SY, Wu Z, Li D, Zhang JT, et al: Primary intracranial extra-axial anaplastic ependymomas. World Neurosurg 2016;90:704.e1-e9.
5.
Mukherjee KK, Salunke P: Uncontrolled spread following radiosurgery for a skull base aspergilloma misdiagnosed as schwannoma: is radiosurgery responsible? Acta Neurochir (Wien) 2016;158:643-646.
6.
Salunke P, Kovai P, Sura S, Gupta K: Extra-axial ependymoma mimicking a parasagittal meningioma. J Clin Neurosci 2011;18:418-420.
7.
Singh V, Turel MK, Chacko G, Joseph V, Rajshekhar V: Supratentorial extra-axial anaplastic ependymoma mimicking a meningioma. Neurol India 2012;60:111-113.
8.
Gupta VK, Kapoor I, Radotra BD, Chatterjee D: Pure extra-axial supratentorial anaplastic ependymoma with no cortical attachment: a rare case. Neurol India 2016;64:345-348.
9.
Aggarwal A, Patra DP, Gupta K, Sodhi HB: Dural tuberculoma mimicking meningioma: a clinicoradiologic review of dural en-plaque lesions. World Neurosurg 2016;88:686.e1-e7.
© 2017 S. Karger AG, Basel
2017
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.