S5446 A Silent Invader: Hepatic Angiosarcoma Presenting as Cirrhotic Decompensation

Introduction: Hepatic angiosarcoma (HAS) is a rare vascular tumor with poor prognosis and rapid progression. HAS has similar symptoms to hepatocellular carcinoma (HCC); however, imaging may appear benign. We present a case of a patient with decompensated cirrhosis who was ultimately diagnosed with HAS on biopsy. Case Description/Methods: A 77-year-old man with recently diagnosed cirrhosis and remote prostate and renal cancer presented with 6 months of weight loss, generalized edema, and abdominal pain. Laboratory studies were remarkable for total bilirubin 3.5 mg/dL, alkaline phosphatase U/L 250, aspartate aminotransferase 111 U/L, ALT 57 U/L, and creatinine 1.6 mg/dL (baseline 1.0). Alpha-fetoprotein and acute vital hepatitis panel were unremarkable. Abdominal magnetic resonance imaging (MRI) suggested cirrhosis, regenerative hepatic nodules, without evidence of hepatocellular carcinoma (HCC). He ultimately improved with supportive care and was discharged home. He returned weeks later with worsened nausea, vomiting, and abdominal pain. Labs revealed worsened bilirubin up to 22 mg/dL. Paracentesis had negative cytology, but due to atypical blood cells revealed on the cell count, there was concern for infiltrative malignancy. Liver biopsy showed poorly differentiated epithelioid and spindle cell malignancy consistent with HAS. Before pathology was finalized, the patient unfortunately suffered a fall resulting in subdural hematoma and herniation. He ultimately passed after being transitioned to comfort care. Discussion: HAS is a rare and aggressive liver tumor that originates from endothelial cells and accounts for less than 2% of primary liver tumors. Patients often present late with vague symptoms such as fatigue, weight loss, and jaundice once the disease is widespread and aggressive. Imaging can be misleading, and lesions are often misdiagnosed as either hemangiomas or regenerative nodules. Definitive diagnosis requires biopsy. Patients are often not candidates for surgical resection due to advanced disease, but even in the setting of surgery, recurrence is common. Liver transplant and systemic therapies have not shown any survival benefit. Due to all of these issues, HAS has a median survival of 5-6 months. Clinicians should maintain suspicion when cirrhotic patients deteriorate unexpectedly without cause as biopsy is the only path to diagnosis.