Chordoid meningiomas of a different histopathological pattern: a report of two cases.

Chordoid meningioma is an uncommon histopathological variant of meningioma with a peculiar chordoma-like appearance. Its association with systemic inflammatory disorder linked to Castleman's syndrome was confirmed in the majority of young patients, however such a relationship in adults remains enigmatic. We report two cases of chordoid meningiomas in adult patients without manifestation of Castleman's syndrome. One tumour was almost totally composed of chordoma-like areas whereas the second one exhibited the unique combination of chordoma- and chondroma-like pattern. This is the first description of chordoid meningioma combined with extensive cartilaginous metaplasia. Both tumours exhibited histological evidence of infiltrative growth, accompanied by a relatively high proliferative index within structures of chordoid appearance. The designation of the chordoid component in meningioma is very important as this subtype of meningioma exhibits a more aggressive biological behaviour and higher risk of recurrence.