A case is presented of a craniopharyngioma arising in and wholly confi
ned to the posterior fossa in a 23-year-old man. The origin of this un
usually located tumour is discussed and comparison made with previousl
y reported ectopic craniopharyngiomas. Most of the cases appeared to b
e either direct extensions from the suprasellar region or recurrences
in locations distant from the original previously treated suprasellar
tumours. We found no evidence in this case to relate the tumour to a s
ellar/suprasellar origin and the craniopharyngioma is believed to have
originated in the posterior fossa.