Multifocal Hepatic Angiosarcoma: Unusual Synchronous Presentation with Pancreatic Acinar Cell Carcinoma, Mimicking Metastatic Liver Disease

Abstract

Hepatic angiosarcoma is a rare malignancy that accounts for 0.5 to 2 % of primary hepatic tumors. Diagnosis of this neoplasm could be challenging because of nonspecific liver biopsy findings and variable clinical and radiological manifestations. We report a case of unusual occurrence of 2 synchronous primary tumors: Acinar cell carcinoma of pancreas and primary multifocal hepatic angiosarcoma that was originally thought to be metastatic disease. 42 year old female presented with vague abdominal pain and significant weight loss of 2months duration. Computed tomography of abdomen showed a 4.8 cm pancreatic head mass and bilobar hypoattenuating hepatic lesions. Endoscopic ultrasound guided biopsy of the pancreatic mass revealed poorly differentiated adenocarcinoma and a PET scan disclosed no extrapancreatic tumor uptake. Therefore, a CT guided biopsy of liver lesions was done to rule out metastatic disease but was inconclusive. An exploratory laparotomy revealed multiple liver lesions. Wedge liver biopsies were taken from segments III and VIII to disclose high grade hepatic angiosarcoma (fig 1) with positive CD31, CD34, vimentin and factor VIII on immunohistochemistry (fig 2). Patient underwent pancreaticoduodenectomy (Whipple's procedure) followed by chemotherapy for the multiple hepatic angiosarcoma lesions.Figure 1Figure 2Primary hepatic angiosarcoma is a rare aggressive vascular neoplasm with high propensity for local recurrence and distant metastasis. This tumor carries an unfavorable prognosis and a median survival of 6 months after diagnosis. All hepatic malignant vascular tumors share histologic characteristics, grow around and into the vessels, and are grossly multifocal. They lack specific clinical presentations and radiological features which makes their diagnosis challenging. They may be misdiagnosed histologically, particularly if only a percutaneous biopsy sample is available, as in our case. Hence, heightened awareness is warranted in such circumstances in order to pursue investigation and prevent delayed detection. Surgical wedge liver biopsy should be obtained for an accurate diagnosis which will require confirmation by immunohistochemical staining. Because hepatic angiosarcomas are often multiple, the main differential diagnosis is metastatic disease. Optimal management of these rare tumors is not well defined but the standard recommended treatment still remains surgical resection for confined liver lesions, followed by radiation and/or chemotherapy.