Intradural Invasion of Chordoma: Two Case Reports

Abstract

Chordomas are rare tumors of the central nervous system and primarily occur in the extradural space. We report two patients with intracranial chordomas located in the region ofthe clivus that invaded the prepontine cisterns. The patients, 45 and 62 years old, had histories ofcranial neuropathies and headache, respectively. Petrosal approaches were performed in both with radical resection of the tumors. Anatomopathological studies confirmed the diagnosis ofchordoma. The symptoms of both patients resolved, and they have had no recurrence after 18 months of follow-up. Intradural chordomas or extradural chordomas that invade the intradural space are difficult to differentiate from ecchordoses physaliphorae, a non-neoplastic entity with similar radiological features. MBI-1 studies were therefore performed to confirm the diagnosis ofchordoma. The differential diagnosis for these two entities, the different modalities of treatment, and prognosis are reviewed.

Giant ecchordosis physaliphora in an adolescent girl

“…The increased propensity of chordoma cells to multiply and grow is underscored by the relatively higher proliferation index of their MIB-1 proliferation marker, which is another helpful distinguishing feature. 9,12,13,17,19,22,25 Ecchordosis physaliphora, instead, is usually slow growing and therefore rarely causes direct symptoms. It is often discovered incidentally as part of an evaluation for unrelated symptoms.…”

Sudden death due to subarachnoid bleeding from ecchordosis physaliphora

“…Immunohistochemistry is useful to support the diagnosis [9]. In particular, the low proliferative activity supports the diagnosis of EP [2,7,12].…”

Benign Notochordal Lesions of the Posterior Clivus: Retrospective Review of Prevalence and Imaging Characteristics

“…6,14 These criteria, while helpful as general guidelines, are not definitive. There are case reports of EP with a high Mib-1 proliferation index 15 or larger than 2 cm 9 as well as reports of chordoma smaller than 2 cm, 10, 13 with a low Mib-1 proliferation index, 8,16 or no associated bone involvement. 2,8,[17][18][19] Since EP and chordoma both derive from embryonic notochordal cells, share common ultrastructural characteristics as well as cell surface markers, and contain the same physaliphorous cells, [20][21][22] no distinguishing and specific pathologic marker is currently available.…”

“…Case reports of symptomatic EP have been described 9,12,15,[23][24][25][26] and a less aggressive intradural variant of chordoma has been found in asymptomatic patients. 8,[17][18][19][27][28][29][30][31][32] These reports highlight the limited prognostic value of clinical features in predicting the aggressiveness of retroclival notochord lesions. Since reliance on clinical features and pathologic analysis for diagnosis is fraught with uncertainty, the imaging evaluation of these lesions is critical.…”