[A case of encapsulated intracerebral hematoma mimicking metastatic brain tumor].

We report a case of encapsulated intracranial hematoma (EIH) mimicking metastatic brain tumor. A 77-year-old male with a medical history of prostate cancer was admitted to our hospital presenting with progressive left hemiparesis. Previous head CT scan and MRI findings during 3 weeks before admission revealed a subcortical acute to subacute hematoma under the right precentral gyrus with growing perifocal brainedema. The Head DSA showed tumor-stain with vascular compression corresponding to the hemorrhagic mass, and Tl-201 SPECT study revealed high L/N ratio (3.0) and high L/E ratio (0.8). The preoperative diagnosis was metastatic brain tumor originating from prostate cancer, and total removal of the mass was undergone with the postoperative diagnosis of EIH. Neither tumoral component nor vascular malformation was found even by detailed pathological study. EIH is a rare variant of intracranial hemorrhage and most of cases in past reports are preoperatively misdiagnosed as malignant brain tumor. In our case, even Tl-201 SPECT and DSA, which are reported as key studies for distinguishing EIH from other brain tumors, demonstrated brain tumor-like findings. It is necessary to consider the possibility of EIH when we encounter hemorrhagic mass in the brain parenchyma even with brain tumor-like radiographical images.