Extracranial Metastasis of IDH-1 Wild Type Glioblastomas

To identify the effects of different immunohistochemical features of glioblastomas with spinal metastases based on the metastatic spread and survival rate.

A total of 214 patients who were diagnosed with and operated for brain tumor in our clinic between 2007 and 2018, and pathologically diagnosed with glioblastoma were retrospectively evaluated. Among them, 141 medical records were reviewed, and 23 of them underwent spinal magnetic resonance imaging postoperatively due to various complaints.

All patients with glioblastoma with spinal metastases had negative isocitrate dehydrogenase 1 (IDH-1) in the immunohistochemical examination. The incidence of spinal metastasis is 1.91%. The median Ki-67 index is 30 (range, 4-90; median Ki-67 index: 30+/-18.5). IDH mutation is wild in 55%, mutant in 33%, and not otherwise specified in 12%. Four patients with spinal metastasis has wild-type IDH with mean Ki-67 index of 60, and one of them was a woman (25%) and the remaining three were men (%75), with mean age of 32 years.

Gliomas with high immunohistochemical proliferation indexes and wild-type IDH with poor prognostic features based on the new classification tended to metastasize to the spine in the early disease stage; therefore, early spinal scanning and radiation therapy might extend the life expectancy. High Ki-67 index and the presence of wild-type isocitrate dehydrogenase may be the predictive factors for spinal screening.