case_images: PMC2823763_01
case_images: (A) Computed tomography scan showing a large mass in the sacrococcygeal space. (B) Magnetic resonance imaging scan showing heterogeneous high intensity in the outer layer and extremely high intensity in the central layer in T2-weighted image.
case_images: 1752-1947-4-8-1.jpg
case_images: PMC2823763_01_1752-1947-4-8-1.jpg
case_images: F1
case_images: Computed tomography (CT) scan showed a mass in the sacrococcygeal space with a smooth surface and no invasion to the rectum (Figure 1A). Magnetic resonance imaging (MRI) showed that the outer layer was heterogeneous with high intensity, and that the central layer had an extremely high intensity in T2-weighted images, indicating that the inside of the mass had a rich blood flow (Figure 1B).
case_images: (A) This is a macroscopic image of the 80 x 75 x 65 mm-sized tumor in the sacrococcygeal space. (B) This image shows the excised tumor with a capsule, with its cut surface mostly grayish white and partially reddish.
case_images: 1752-1947-4-8-2.jpg
case_images: PMC2823763_01_1752-1947-4-8-2.jpg
case_images: F2
case_images: The tumor was completely removed (Figure 2A). Its cut surface was mostly grayish-white and partially reddish (Figure 2B).
case_images: (A) Hematoxylin and eosin staining revealing spindle-shaped cells surrounding the endothelial-lined vascular spaces. (B) Immunohistochemistry demonstrating CD34 positive tumor cells. (C) Immunohistochemistry demonstrating Bcl-2 negative tumor cells.
case_images: 1752-1947-4-8-3.jpg
case_images: PMC2823763_01_1752-1947-4-8-3.jpg
case_images: F3
case_images: Histopathological features of the hematoxylin and eosin staining revealed that the tumor contained spindle-shaped cells surrounding the endothelial-lined vascular spaces, which is consistent with the histology of hemangiopericytoma (Figure 3A). The mesenchymal tumor cells in our patient stained positive for CD34 (Figure 3B) and vimentin, and negative for Bcl-2 (Figure 3C), CD99, c-kit, factor VIII, desmin, alpha-smooth muscle actin, S-100 protein, epithelial membrane antigen, and keratin.