Osteoblastic metastases from astrocytomas: A report of two cases

The spread of primary central nervous system (CNS) neoplasms beyond the confines of the neuraxis is a relatively uncommon observation. Extraneural metastases involving bone are quite rare, and have been observed almost exclusively in cases of medulloblastoma, high‐grade (III‐IV) astrocytoma, and glioblastoma multiforme. To date there has been only one case reported of bone metastasis from a “well‐differentiated” astrocytoma. We now report two cases of astrocytoma in children with diffuse osteoblastic metastases and a fulminant clinical course. These cases demonstrate that due to the potential morphologic heterogeneity of these neoplasms, an initial biopsy diagnosis of low‐grade astrocytoma does not always imply a benign clinical course.