[Multilocular chronic intracerebral hematoma due to metastatic brain tumor: a case report].

Chronic intracerebral hematoma is a fairly rare clinical entity. We report a case of a 76-year-old man who presented with left hemiparesis on admission. CT scan revealed a hematoma in the right basal ganglia. Under observation, the hyperdense lesion on CT scan changed to isodense 2 weeks after admission and then changed to low density 4 weeks after the first scan. These findings suggested hypertensive intracerebral hemorrhage but, 3 months after admission, hemiparesis grew worse and the appearance of the lesion changed from low density to isodensity again. When the patient presented disturbance of consciousness, CT scan revealed a new hemorrhage from the capsule of the hematoma and the new hematoma markedly expanded 2 weeks later. The contents of the hematoma was old uncoagulated hematoma resembling chronic subdural hematoma and drainage was carried out under local anesthesia. The patient died because of respiratory failure and autopsy was performed. Histopathologically cancer cells were shown in the hematoma cavity and the capsule of the hematoma was composed of two layers: a collagenous layer on the inside and a granulation layer with neovascular system on the outside. As the neovascular system existed on the outside of the capsule, the rebleeding occurred outside the capsule and the second hematoma appeared beside the initial one. We suspected that the initial bleeding occurred in the tumor tissue and the rebleeding occurred in the granulation layer of the capsule.