Undifferentiated Pleomorphic Sarcoma of Liver: Case Report and Review of the Literature.

Undifferentiated pleomorphic sarcoma (UPS), previously known as malignant fibrous histiocytoma (MFH), is rarely reported in the liver as a primary site. We report a case of a previously healthy 56-year-old male, who presented with abdominal pain and jaundice. The patient was originally diagnosed with cholecystitis, treated with cholecystectomy, which was complicated by abdominal abscess. One week following discharge, the patient was readmitted with fever, chills, and leukocytosis. Computed tomography (CT) guided liver biopsies demonstrated an epithelioid to spindle cell neoplasm with markedly atypical nuclei and prominent necrosis infiltrating between hepatocytes. Immunohistochemical studies were negative for epithelial, melanocytic, and hematolymphoid differentiation. Positron emission tomography (PET) was performed, which showed a single markedly hypermetabolic central hepatic mass (14 x 8.5 x 8.5 cm) with likely central necrosis, consistent with primary malignancy. The patient was treated with one cycle of chemotherapy (doxorubicin and ifosfamide), refusing additional cycle due to medication side effects. The patient subsequently succumbed to complications associated with the malignancy and died within 19 days of diagnosis.