A Rare Case of Glioblastoma With Extensive Liver Metastases

Glioblastoma (GBM), the most common primary brain tumor, is a highly aggressive malignancy for which the median survival is about 13 months, and 5-year survival is well under 5%. These tumors usually occur in the brain and enlarge and infiltrate through white matter, including crossing through the corpus callosum to the opposite cerebral hemisphere. They may spread to distant parts of the central nervous system (CNS) via cerebrospinal fluid pathways. Extraneural metastases from primary brain tumors are quite rare, for 2 probable reasons: because most patients survive less than 2 years, and because of the absence of true lymphatics in the CNS. Typical sites for distant extraneural metastasis of GBM are lungs and pleura, followed by lymph nodes and bones; spread to the liver is exceptional. Most of the reported cases with liver metastases had either single or only a few such metastatic lesions. We report a probably unique case of GBM with extensive liver metastases along with a review of previous cases of liver metastasis from GBM, and we discuss the possible mechanisms of metastasis.