[A case of acute subdural hematoma due to dural metastasis from malignant pleural mesothelioma].

A rare case of acute subdural hematoma due to dural metastasis from malignant pleural mesothelioma is reported. A 65-year-old man was brought to a nearby hospital complaining of lumbago. He suddenly complained of headache on the third hospital day and fell into a deep coma within a short while. Computed tomography showed a crescent shaped high density area in the right fronto-temporo-parietal region with midline shift to the left side. He was admitted as an emergency case to our clinic on April 24, 1989. Under the diagnosis of acute spontaneous subdural hematoma, emergency operation was performed. Nests of malignant sarcomatous cells were found in the clot obtained during the procedure, but the origin of the tumoral cells could not be identified. The patient failed to recover from the comatose state and died with pancytopenia on the 17th hospital day. General autopsy showed wide-spread malignant pleural mesothelioma with metastases to the lung, liver and bone marrow. Examination of the head revealed dural metastatic tumor and a subdural hematoma over the left hemisphere. Histopathology showed that many tumor cell nests were found only within the dilated veins of the dura. There, acute subdural hematoma was assumed to have developed suddenly and there was massive bleeding from the capillaries of the inner vascular layer of the dura. The relevant literature about intracranial metastasis of malignant pleural mesothelioma was reviewed, and the mechanism of subdural hematoma due to dural metastasis from malignant tumor was discussed.