PMC4808538_01
MRI images of axial section ((a-b), T1 and T2 weight) and coronal sections ((c-d), T1 and T2 weight); MRI images of sagittal section (e) showed the enhancing of the tumour mass involving the tongue base after gadolinium administration in T1 weight.
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fig1
MRI evidenced a capsulated, solid oval mass, with well-defined margins, of 31 x 28 x 21 mm on T1-weighted images without contrast; it was hyperintense and slightly inhomogeneous on the T2-weighted images, while T1 weighted images with contrast (gadolinium) showed remarkable enhancement of the mass (Figure 1).
Cytological smears ((a), Papanicolaou staining) and histological sections from cytoinclusion ((b), H&E staining) showed nests of epithelioid cells, strongly positive for anti-pan-cytokeratin (c), anti-HMWCK, and S-100 (e) antibodies ((a-e): magnification 400x).
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fig2
Immunohistochemistry was positive for pan-cytokeratin, high molecular weight cytokeratin (HMWCK), and S-100 and negative for alpha-smooth muscle actin (Figure 2).
Histological specimens showing solid nests of plasmacytoid cells surrounded by thin fibrous stroma ((a), H&E staining) displaying diffuse immunoreactivity for S-100 (b) and focally for alpha-smooth muscle actin (c) and CK7 (d) ((a-d): magnification 400x).
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fig3
At light microscopy, the H&E stained sections showed a neoplasm made up of plasmacytoid cells arranged in solid nests, with microcystic spaces and surrounding myxoid stroma or thin fibrous septa, displaying strong and diffuse immunoreactivity for S-100 protein and focally for alpha-smooth muscle actin, CK7, and p63 (Figure 3).