A man aged 69 years presented with acute right flank pain secondary to a hemorrhagic large adrenal tumor. En bloc resection was performed to repair the inferior vena cava. Immunoperoxidase levels in the tumor were positive for factor VIII and CD31 and negative for S100, protein Melan-A, CD34, synaptophysin, chromogranin, desmin, muscle specific actin, ETFA (EMA), KRT20 (CK20), CDX2, TTF1, LNPEP (PLAP), inhibin, ?-fetoprotein, CD30, hepatocyte paraffin, and aberrant expression of cytokeratin 7 and pankeratin. The pathological diagnosis was consistent with adrenal angiosarcoma. Obtaining appropriate immunoperoxidase stains and multidisciplinary evaluation helped make the diagnosis of this rare adrenal tumor and determine its management. The patient had an uneventful postoperative course and completed 4 cycles of adjuvant chemotherapy with doxorubicin/ifosfamide and adequately tolerated the treatment. However, positive surgical margins were found, so he was referred to radiation oncology specialists for possible adjuvant radiotherapy to the surgical bed. Weeks after the first initiation of therapy, the patient presented to the emergency department complaining of shortness of breath, fatigue, and generalized weakness for 3 days. He was admitted and found to have new-onset anemia and a new-onset, large, right pleural effusion. Thoracentesis performed showed sanguinolent fluid that, after microscopic evaluation, was suggestive of recurrent malignancy. Thoracic aortography performed with subselective catheterization to several arteries (right bronchial, right phrenic, and right renal arteries) did not show any active bleeding. However, the right inferior intercostal and adrenal arteries were presumed to be the reason for the bleeding event, so they were embolized until stasis. The patient remained hemodynamically unstable but eventually experienced multiorgan failure. In spite of aggressive measures, he died 10 days after admission to the hospital.