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

Abstract

Many notochordal lesions do not fit neatly into the diagnostic criteria for either EP or chordoma. It may be useful to consider these atypical cases along a spectrum of notochord remnant lesions. Close inspection of imaging reveals BNCTs at a similar frequency to its pathologic prevalence. BNCTs such as EP vary in size and may be easily overlooked.

Resección endoscópica de cordoma del clivus. Descripción de un caso

“…BNCT may also undergo malignant transformation to classic chordoma. On MRI, these two benign tumors most often do not show contrast PREPRINT Revista ORL (Ediciones Universidad de Salamanca / Salamanca University Press) enhancement, which usually occurs in chordomas [6]. However, contrast enhancement is not pathognomonic of chordoma, and the differential diagnosis with these two benign entities can't be definitive only with image studies.…”

“…It should be noted that about 40% of chordomas are in the clival and para-clival regions [6]. These tumors have a slow growth pattern, with propensity for local invasion.…”

“…Most frequent sites include lung, bone, liver and lymph nodes [3]. Differential diagnoses include ecchordosis physaliphora and benign notochordal cell tumor (BNCT), both benign lesions derived from remnant cells of the primitive notochord and primarily involving the clival region [6,7]. BNCT may also undergo malignant transformation to classic chordoma.…”

“…In the present case, the clivus lesion was an accidental finding, and although with no contrast enhancement on MRI (which usually occurs in the chordoma) the underlying bone erosion has alerted us to the possibility of a malignant lesion. In the suspicion of a malignant lesion, it is preponderant to perform a surgical biopsy for confirmation, since the definitive diagnosis of chordoma is histological [6]. These tumors usually present in advanced stages, causing symptoms by invasion of neighboring structures by tumor growth [3].…”

“…However, contrast enhancement is not pathognomonic of chordoma, and the differential diagnosis with these two benign entities can't be definitive only with image studies. As so, suspected clival lesions must be biopsied for a definitive diagnosis [6,7]. The recommended treatment for clivus chordomas is complete surgical resection and postoperative RT [4,9].…”