Nonenhancing intracranial intradural chordoma mimicking an epidermoid cyst on magnetic resonance imaging: a case report.

Chordomas are relatively rare malignant tumors derived from embryonic notochord remnants. Most intracranial chordomas show extradural extension and cause bone erosion. However, a small percentage of these tumors are exclusively intradural and tend to show less aggressive features, although local recurrence and metastatic spread have been described. Intradural chordomas with imaging features similar to epidermoid cysts are exceedingly rare. We describe the case of a nonenhancing and nondestructive intradural prepontine chordoma showing restricted diffusion on magnetic resonance imaging on a 44-year-old man who presented with acute-onset vertigo and vomiting. Subtotal resection of the lesion was performed followed by adjuvant radiation therapy. Histopathological examination revealed a chordoma. This case report highlights the need to include intradural chordomas in the differential diagnosis of a nonenhancing and nondestructive prepontine intradural lesion demonstrating restricted diffusion. Gross total resection, adjuvant radiation therapy in cases of macro/microscopical residual disease and regular follow-up imaging assessment are warranted due to the possibility of local recurrence and metastatic dissemination.