Undifferentiated Embryonal Sarcoma of the Liver

Abstract

Purpose: A 44 yo woman who has been complaining of RUQ pain for the past year was referred to our clinic for evaluation of a hepatic mass. She has also been complaining of 60 pound weight loss, anorexia, and abdominal fullness. Her past medical history is significant for caesarian section × 3, cholecystectomy and depression. Her physical exam demonstrates a large right upper quadrant, solid, smooth mass. Pertinent initial labs: Hct 40.1, LFTs normal, AFP 24.9. An initial abdominal ultrasound, abdominal CT scan and abdominal MRI demonstrated a 15 cm complex multiloloculated mass with hemorrhagic areas of various age. The origin of the mass was indeterminate and either hepatic, renal or ovarian in origin. An angiogram was performed which demonstrated perfusion from the right hepatic artery. The patient was taken to the operating room for diagnostic laparotomy as well as potential resection. The surgical specimen was multiloculated and demonstrated areas of necrosis as well as hemorrhage. Serous fluid was present and some areas showed a well-developed capsule. Pathology showed a somewhat varied morphologic pattern with some areas showing a pursed spindle cell pattern with a moderate to high mitotic rate and others showing an epithelioid pattern or a myxoid pattern. Immunoperoxidase stains: Vimentin positive, Cytokeratin (CAM5.2 and AE1:3) focally positive, Desmin focally positive, Actin questionably positive, C-kit negative, S100 negative, Mart 1 negative and CD34 negative. A diagnosis of undifferentiated embryonal sarcoma of the liver was made. Undifferentiated Embryonal Sarcoma is an extremely rare diagnosis in adults over the age of 15 and most cases are in the pediatric population. There is a female predominance and most of these sarcomas arise in the right hepatic lobe. Surgical specimens are composed of cystic or gelatinous tissue and scattered hemorrhage and necrosis may be present. Microscopy and immunohistochemical stains are consistent with an undifferentiated sarcoma. We present this classic case of an extremely rare undifferentiated embryonal sarcoma presenting as a large symptomatic hepatic mass. The overall prognosis of this diagnosis is poor with a potentially high recurrence rate within two years of diagnosis. Our patient has completed four cycles of doxorubicin and ifosfamide/mesna without evidence of recurrence 6 months after surgery.