Abstract
Cardiac angiosarcoma is a malignant tumor derived from vascular endothelium with a dismal prognosis. The imaging findings of cardiac angiosarcoma are nonspecific and endomyocardial and pericardial biopsies have insufficient accuracy. For these reasons, the diagnosis is sometimes difficult. Primary and metastatic tumors tend to bleed easily, causing hemoptysis and neurological symptoms. Brain metastases are not often known to be fatal when they cause hemorrhage. We report a 27-year-old man diagnosed with right atrium angiosarcoma, with metastases in the lung, brain, and bone. The patient had only respiratory symptoms at the first visit and did not show any symptoms derived from brain metastases yet died after 27 days due to hemorrhage from brain metastases. If brain metastasis from angiosarcoma is suspected based on imaging findings, urgent radiotherapy should be considered before histological examination for a definitive diagnosis.