Chondromyxoid fibroma of the skull base invading the occipitocervical junction: report of a unique case and discussion.

Chondromyxoid fibroma (CMF) is a rare bone tumor representing less than 1% of total bone neoplasms. It is a slow-growing, locally destructive tumor that usually affects the metaphyseal region of long bones. The occurrence of this tumor in the skull base or cervical spine is exceptionally rare. We present the first case of CMF originating in the clivus and extending into the atlas and discuss the surgical management of this case.