A Case of Putaminal Hemorrhage Caused by Underlying Tectal Glioblastoma

We report a case of glioblastoma due to putaminal hemorrhage. Notably, the glioblastoma was located at some distance from the hematoma. A 42-year-old right-handed man presented with a sudden-onset headache, motor aphasia, and right hemiplegia. CT showed left putaminal hemorrhage and a mass lesion with a slightly high density in the midbrain away from the hematoma. Conservative treatment was initiated for the patient. Initially, we suspected a benign tumor-like cavernous malformation based on the CT findings. However, MRI showed ring enhancement of the mass lesion on contrast-enhanced MRI and hyperintensity on arterial spin labeling(ASL). A part of the wall of the putaminal hemorrhage also exhibited hyperintensity on ASL. Since we suspected a malignant brainstem tumor and a secondary intracerebral hemorrhage caused by this tumor, we performed a stereotactic brain biopsy. Histological examination revealed that the tumor was a wild-type IDH-1 glioblastoma. In the acute phase, the intracerebral hemorrhage presented as a hyperintensity on T1-weighted imaging. Therefore, it was difficult to distinguish hemorrhagic glioblastoma from an intracerebral hemorrhage. Even if an intracerebral hemorrhage is observed at common sites, it is important to consider the possibility of a malignant brain tumor and complete a prompt examination. In addition, ASL imaging may be useful in detecting hemorrhagic malignant brain tumors.