Glioblastoma multiforme of the cerebellum.

Glioblastoma multiforme (GBM) is a highly malignant glial tumor seen commonly in the cerebral hemispheres, but rarely encountered in the cerebellum. It may occur at any age, but is seen more often in adult age groups. Despite its rarity, GBM should be considered in patients with a ring-enhancing lesion in the cerebellum.