J Neurol Surg B Skull Base 2022; 83(S 02): e96-e104
DOI: 10.1055/s-0040-1722717
Original Article

Do All Notochordal Lesions Require Proton Beam Radiotherapy? A Proposed Reclassification of Ecchordosis Physaliphora as Benign Notochord Cell Tumor

1   Queen's Medical Centre, Nottingham, United Kingdom
,
Istvan Bodi
2   Department of Neuropathology, King's College Hospital, London, United Kingdom
,
Prajwal Ghimire
3   Department of Neurosurgery, King's College Hospital, London, United Kingdom
,
Konstantinos Barkas
3   Department of Neurosurgery, King's College Hospital, London, United Kingdom
,
Sinan Al-Barazi
3   Department of Neurosurgery, King's College Hospital, London, United Kingdom
,
Nick Thomas
3   Department of Neurosurgery, King's College Hospital, London, United Kingdom
,
Eleni C. Maratos
3   Department of Neurosurgery, King's College Hospital, London, United Kingdom
› Institutsangaben
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Abstract

Objectives Ecchordosis physaliphora (EP) is a benign notochord lesion of the clivus arising from the same cell line as chordoma, its malignant counterpart. Although usually asymptomatic, it can cause spontaneous cerebrospinal fluid (CSF) rhinorrhea. Benign notochordal cell tumor (BNCT) is considered another indolent, benign variant of chordoma. Although aggressive forms of chordoma require maximal safe resection followed by proton beam radiotherapy, BNCT and EP can be managed with close imaging surveillance without resection or radiotherapy. However, while BNCT and EP can be distinguished from more aggressive forms of chordoma, differentiating the two is challenging as they are radiologically and histopathologically identical. This case series aims to characterize the clinicopathological features of EP and to propose classifying EP and BNCT together for the purposes of clinical management.

Design Case series.

Setting Tertiary referral center, United Kingdom.

Participants Patients with suspected EP from 2015 to 2019.

Main Outcome Measures Diagnosis of EP.

Results Seven patients with radiological suspicion of EP were identified. Five presented with CSF rhinorrhea and two were asymptomatic. Magnetic resonance imaging features consistently showed T1-hypointense, T2-hyperintense nonenhancing lesions. Diagnosis was made on biopsy for patients requiring repair and radiologically where no surgery was indicated. The histological features of EP included physaliphorous cells of notochordal origin (positive epithelial membrane antigen, S100, CD10, and/or MNF116) without mitotic activity.

Conclusion EP is indistinguishable from BNCT. Both demonstrate markers of notochord cell lines without malignant features. Their management is also identical. We therefore propose grouping EP with BNCT. Close imaging surveillance is required for both as progression to chordoma remains an unquantified risk.

Statement of Ethics

For all manuscripts reporting data from studies involving human or animal participants, formal review and approval, or formal review and waiver (exemption), by an appropriate Institutional Review Board (IRB) or ethics committee is required, as well as any necessary HIPAA (The Health Insurance Portability and Accountability Act 1996) consent, and should be described in the Methods section with the full name of the reviewing entity. All clinical trials must be registered in a public trials registry. Denote the registry and registry number.




Publikationsverlauf

Eingereicht: 20. Januar 2020

Angenommen: 27. November 2020

Artikel online veröffentlicht:
12. März 2021

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