Angiosarcoma is a rare and aggressive type of tumor with a differentiation toward vascular endothelium, accounting for 2% of soft tissue sarcomas [1]. Angiosarcoma can arise in any part of the body, but is found most commonly in cutaneous lesions and rarely arises from visceral organs [2]. Specifically, a primary angiosarcoma of the pancreas is extremely rare, having so far only six cases reported (Table1) [4-9]. Five out of seven cases (including ours) expired within two months after the initial diagnosis or surgery. In this case, multiple liver metastases and dissemination appeared within two months after surgery in spite of gross complete resection, indicating the extremely aggressive feature of this tumor.
The correct diagnosis of angiosarcoma is challenging as it is an exceedingly rare disease related to the pancreas with most patients showing signs and symptoms, such as abdominal pain, anemia, gastrointestinal bleeding, melena, or obstructive jaundice. Hemobilia of the present case was induced by the tumor imploding into the intrapancreatic bile duct. Kim KH et al. had previously reported two cases of hemobilia induced by pancreatic cancer [10], but pancreatic tumor is a rare cause for hemobilia [11]. Hemosuccus pancreaticus is a rare presentation of pancreatic disease, including primary pancreatic tumor, such as pancreatic carcinoma, serous/mucinous cystic neoplasms, and neuroendocrine tumor [12]. There has been no report, however, about hemosuccus pancreaticus caused by pancreatic hemangiosarcoma.
Furthermore, hepatic or splenic origin is common among angiosarcomas in visceral organs. A heterogeneous look that reflects hemorrhage, fibrosis, and necrosis is common within the imaging features in visceral angiosarcoma according to the previous review [13]. In this case, the CT and MRI showed an expansile and well-circumscribed tumor with a heterogeneous internal density which is clearly different from invasive ductal carcinoma of the pancreas. Hypervascular component indicated other primary pancreatic tumors, such as acinar cell carcinoma, adenosquamous cell carcinoma, solid pseudopapillary tumor, and intraductal papillary mucinous carcinoma as differential diagnoses. Histological features of angiosarcoma are various among cases, and as Darre reported biopsy should be a possible way to definitive diagnose of this tumor [8]. Tumor cells may present rounded, polygonal, or spindle-shaped configurations, and immunohistochemistry is needed to confirm its differentiation in relation to vascular epithelium. Typically, angiosarcomas express Factor-VII, CD31, CD34, and vascular endothelial growth factor (VEGF) [14].
Even though there is limited data regarding the treatment of angiosarcoma and there is no consensus as to its algorithm, surgery with complete resection is thought to be the primary and most reliable treatment for local diseases [15] whereas radiotherapy or chemotherapy is considered to conduct for unresectable angiosarcoma. The 5-year overall survival (OS) rate in all angiosarcoma is about 30%–40% [16, 17]. The 5-year OS rate of visceral angiosarcoma is under 20%, while that of angiosarcoma arising in the other location is about 60%. Moreover, the 5-year OS of angiosarcoma with metastases is reported nil [15]. Worth et al. reported a case of one-year survivor without recurrence after robotic-assisted distal pancreatectomy for a 31 × 24 mm lesion in the pancreatic tail [7].Metastases at presentation, visceral, or deep soft tissue tumor location, tumor size >5cm, presence of tumor necrosis and the absence of surgical resection are reportedly associated with a poor prognosis [17]. In this case, metastases had developed within two months and patient died 42 days after surgery. The rupture of the liver metastases might have resulted in peritoneal dissemination.
It is worth pointing out another reported case who died 15 days after surgery who showed hemobilia and an aggressive intraperitoneal bleeding from multiple liver metastases [4], to which we performed TAE in order to control it. The hemobilia in these two patients presented might indicate an aggressive character and the hemorrhagic disposition of the tumor. Although this is the first report that TAE was performed for metastases from primary angiosarcoma of the pancreas, a previous study suggests emergent TAE for the primary hepatic angiosarcoma is considered to be the primary procedure to stop acute intraabdominal bleeding [18].
To summarize, in the present study we reported a primary angiosarcoma of the pancreas, primary and recurrent lesions, which presented fatal bleeding, which indicate a tumor of this nature should be accounted for in the presence of hemobilia and a visible and heterogeneous look.