[Subarachnoid hemmorrhage and aneurysmal change of cerebral arteries due to metastases of chorioepithelioma (author's transl)].

An episode of subarachnoid hemorrhage was seen on a 22-year-old married woman, which followed vaginal spotting and convulsive seizure. The neurological examination revealed bilateral papilledema, retinal hemorrhage, neck stiffness, Kernig's sign abducens paresis on the right. The chest X-ray film showed a spherical mass lesion in the right lung. The pelvic examination disclosed no pathological findings, however, HCG (human chorionic gonadotropin) in the urine increased significantly. Intracranial metastasis of chorioepithelioma was the tentative diagnosis at the admission and the right caroid angiography was performed, which demonstrated a fusiform aneruysm of the right middle cerebral artery beside arterial shift indicating a metastatic mass lesion in the parietal lobe. At surgery the tumor was removed and the arterial change was resected. Histologically the tumor was verified and the aneurysm was produced by metastasis of the tumor to the intima and interruption of the internal elastic membrane. She was placed on the anticarcinogenic agent and later the mass lesion in the chest was operated and irradiated. The postoperative carotid angiography showed another berry-shaped aneurysm arising from the right calloso-marginal artery. After the serial treatment with Actinomycin D the aneurysm disappeared completely and the arterial branch distal to the aneurysm was thrombosed. The patient is still alive 3 years after the onset of illness. An emphasis was placed that the neurosurgeon should be aware of cerebrovascular changes due to metastasis of the chorioepithelioma while making diagnosis of subarachnoid hemorrhage of the female patients who belong to the reproductive age. Intracranial aneurysmal change due to metastatic infiltration to the arterial wall was reported.