Metastatic glioblastoma: case presentations and a review of the literature.

Extracranial metastases from glioblastoma (GBM) are uncommon with an estimated incidence of less than 2%. We report two cases of metastatic GBM seen within an 8-week period followed by a literature review. We attempted to identify common factors or a causative mechanism. Factors that predominated among the reviewed cases included male gender, tumor location, and younger age. Causative mechanisms were not apparent. While metastatic disease remains rare, it might be occurring with increasing frequency. This trend might be due to increased diagnosis, better imaging, a more extensive physician workup, or an increase in survival. Metastatic GBM can present and progress quite rapidly, and repeat evaluations of persistent or worsening complaints among GBM patients are warranted. Early diagnosis of metastatic disease spread can help to expedite alleviation of patients' discomfort, in an already aggressive disease process.