PMC8519692_01
Microscopically, a solid tumor infiltrates the submucosa ((a); H&E, 40x), displaying areas of geographic necrosis ((b); H&E, 200x). On higher magnification ((c); H&E, 400x), cherry-red nucleoli are conspicuous and numerous mitosis and apoptosis figures can be recognized. Neoplastic cells were positive for HMB-45 ((d); 400x), SOX-10 ((e); 400x), and Melan-A ((f); 400x) immunostaining.
CRII2021-5516004.001.jpg
PMC8519692_01_CRII2021-5516004.001.jpg
fig1
Histomorphology and immunohistochemical profiles suggested the diagnosis of mucosal melanoma (Figure 1).
Initial MRI images: (a, c) axial and coronal T1WI, (b, e) axial and coronal T2WI, and (c, f) axial and coronal T1WI after gadolinium intravenous administration. The left nasal, ethmoidal, and sphenoidal lesion (grey arrows) can be seen with cavernous extension (solid white arrows), with low signal on T1WI and T2WI and homogeneous enhancement after contrast administration, with sinus obstruction and retention of secretions in ethmoid and sphenoid sinuses (dashed white arrows). MRI, magnetic resonance imaging; WI, weighted image.
CRII2021-5516004.002.jpg
PMC8519692_01_CRII2021-5516004.002.jpg
fig2
Computed tomography (CT) and magnetic resonance imaging (MRI) identified a 4 cm x 2.2 cm x 3.7 cm lesion in the posterior half of the left nasal fossa (Figure 2).