PMC3964668_01
Axial computed tomography of the abdomen demonstrating a tumour (T) in the terminal ileum, which appears thick walled, located close to the caecal pole (C), mimicking an appendiceal abscess
rcse9501-e7-01.jpg
PMC3964668_01_rcse9501-e7-01.jpg
fig1
Abdominal computed tomography (CT) demonstrated a 10cm x 6cm x 4cm thick-walled mass adjacent to the caecal pole with a proximally dilated small bowel (Fig 1).
Segmental small bowel resection (A) with intestinal wall opened longitudinally along the antimesenteric border (B) to reveal a large mural angiosarcoma
rcse9501-e7-02.jpg
PMC3964668_01_rcse9501-e7-02.jpg
fig2
Consequently, a 17cm segment of ileum containing the tumour was resected (Fig 2) and a stapled anastomosis was performed.  
Haematoxylin and eosin stain of angiosarcoma demonstrating cellular pleomorphism with spindled and epithelioid shaped cells (A), primitive vessel formation (B) and positive cell membrane staining for the endothelial marker CD31 (C); 200x magnification
rcse9501-e7-03.jpg
PMC3964668_01_rcse9501-e7-03.jpg
fig3
Tumour morphology was suggestive of high grade sarcoma (Figs 3a and b), and consisted of cellular pleomorphism with mixed sheets of spindled and epithelioid cells, extensive areas of necrosis and cystic degeneration, cytoplasmic vacuolisation and intercellular vasoformation. Subsequent immunohistochemistry demonstrated a diffuse, strong positive reaction to endothelial markers (CD31 and CD34), and negative staining for stromal (CD117 and DOG1), smooth muscle (desmin), epithelial (MNF116), melanocytic (melan-A, HMB-45) and neural (S100) tissue markers, which together established the diagnosis of an angiosarcoma (Fig 3c).