Abstract
Astrocytomas of the pons and medulla oblongata ('brain-stem gliomas') while often invasive locally, do not as a rule seed and metastasize along the spinal meninges. Three cases are here reported (two adults, one child) in whom astrocytoma of the brain-stem metastasized along the spinal cord. The dura mater itself and the spinal epidural space were invaded in two cases. The child and one adult had a pontine astrocytoma, the other adult's tumour originated in the medulla oblongata. In the two cases that came to necropsy the tumour of the brain-stem was much better differentiated than the meningeal deposits. These three cases suggest that the possibility of spinal spread of brain-stem gliomas should be considered when dealing with diagnostic and therapeutic problems of such patients.