PMC5225335_01
Enhanced CT scan showed a heterogenous round mass in the presacral space (diameter: 43 mm) that contained low-density areas ((a) plane, (b) arterial phase).
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Contrast-enhanced CT was performed, which revealed a heterogenous mass in the presacral space (diameter: 43 mm) that contained low-density areas suggestive of fatty components and some slight enhanced areas suggestive of soft tissue islands inside the mass (Figure 1).
MR images showed a round heterogenous tumor in the presacral space ((a) T1-weighted, (b) T2-weighted, (c) fatty-saturated T2-weighted, and (d) diffusion-weighted image (b = 800) and (e) ADC map).
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Subsequent pelvic magnetic resonance imaging (MRI) showed a 43 mm mass in the anterior aspect of the sacrum (Figure 2).
A tumor located in the anterior of the sacrum and consisting of soft, yellowish tissue. The mass was poorly defined and strongly adherent to the sacrum and the common iliac vein.
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The mass was poorly defined and strongly adherent to the sacrum and the common iliac vein (Figure 3).
Histopathology of the tumor shows mature adipose tissue mixed with hematopoietic tissue, which included erythrocytes, myelocytes, and megakaryocytes. Immunohistochemical staining confirmed the presence of hematopoietic elements consisting of myeloperoxidase-positive myeloid elements and factor VIII-positive megakaryocytes (HE stain (a) x400, (b) x40, (c) myeloperoxidase-positive myeloid elements, and (d) factor VIII-positive megakaryocytes).
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Immunohistochemical staining confirmed the presence of hematopoietic elements consisting of myeloperoxidase-positive myeloid elements and factor VIII-positive megakaryocytes (Figure 4).