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Duodenal metastasis from subcutaneous angiosarcoma of the head: Rare cause of obscure gastrointestinal bleeding

A 65-year-old man with a history of surgery for subcutaneous angiosarcoma of the head 2 years previously was referred to Mie University Hospital to examine the cause of iron deficiency anemia. At another hospital, he had undergone upper endoscopy, colonoscopy and capsule endoscopy, all of which failed to show the cause of bleeding and anemia. Initial laboratory testing at our hospital revealed a hemoglobin level of 5.3 g/L. In a subsequent esophagogastroduodenoscopy, we could not detect the site of bleeding. Abdominal computed tomography was also done, and results were unremarkable. Because of persistent anemia, double balloon enteroscopy by the antegrade approach was carried out, and we found several dark red nodules in the third portion of the duodenum. The nodules were hemorrhagic-appearing tumors, each measuring approximately 1 cm in diameter (Fig. 1). Endoscopic biopsies revealed infiltrating tumors that were composed of vascular channels and were positive for an endothelial marker (CD31), the results of which were consistent with angiosarcoma of the duodenum (Fig. 2). According to the clinical course, we concluded that the patient had duodenal metastasis of an angiosarcoma. No additional treatment was given because of his poor overall status. Angiosarcoma is a rare soft tissue neoplasm comprising 1–2% of all sarcomas. It frequently involves the skin and subcutaneous tissues with a high metastatic rate and poor prognosis. The most common sites of metastasis are the liver, lung, lymph nodes, bone, bone marrow and soft tissue.Angiosarcoma occurs very rarely in the intestinal tract as either a primary or a metastatic tumor. Only one case has been diagnosed as a metastatic angiosarcoma to the duodenum. To the best of our knowledge, this is the second case report of duodenal metastasis from a primary angiosarcoma presenting as a rare cause of obscure gastrointestinal bleeding.