Chordoma coexisting with Rathke's cleft cyst: case report and literature review.

Both chordoma and Rathke's cleft cyst are relatively rare diseases in the central nervous system. In this paper we report the first case of a chordoma coexisting with a Rathke's cleft cyst. A 49-year-old man presented with a 19-month history of distending pain, movement dysfunction and diplopia of the left eye. The preoperative diagnosis was consistent with chordoma with cystic change. Final pathological diagnosis of chordoma coexisting with Rathke's cleft cyst was made according to histological and immunohistochemical studies and the clinical and radiological features are discussed. Considering the close relationship between the notochordal tissue and Rathke's pouch during early embryogenic development, a possible mechanism is also discussed with the literature review.