Multifocal primary central nervous system angiosarcoma: illustrative case.

Background: Angiosarcoma is a malignant mesenchymal tumor derived from vascular endothelial cells in which a primary intracranial origin is extremely rare. Most previous reports of primary central nervous system (CNS) angiosarcoma have been solitary cases.

Observations: The authors report a case of primary CNS angiosarcoma that caused the development of multiple disseminated cerebral hemorrhagic lesions within a short period of time. This rapid progression of symptoms resulted in the death of the patient. During surgery, several nodules suggestive of a tumor were removed from just below the surface of the brain, mixed into the hematoma. A pathological examination revealed atypical cells mimicking blood vessels in the subarachnoid space that were positive for specific vascular endothelial markers.

Lessons: In this case, multifocal angiosarcoma occurred on the brain surface and ventricles, suggesting cerebrospinal fluid dissemination. If multiple cerebral hemorrhages are found on the brain surface, multifocal angiosarcoma should also be considered.