case_images: PMC7395541_01
case_images: (a) Noncontrast head CT (axial cut) at time of presentation, showing large bifrontal mass (light blue lines) surrounded by brain edema (red lines), causing significant mass effect. (b) Sagittal cut. The tumor has destroyed the frontal bone, extending into the paranasal sinuses (arrow) and intracranially, involving the anterior skull base.
case_images: SNI-11-195-g001.jpg
case_images: PMC7395541_01_SNI-11-195-g001.jpg
case_images: F1
case_images: Extended peritumoral brain edema with significant mass effect was also noted [Figure 1].
case_images: (a) Histological examination for hematoxylin and eosin (H&E) stain showing a tumor comprised small to medium size cells, some of them with clear cytoplasm. Rhabdoid cells were not noted. The tumor shows areas of necrosis. (b) H&E, x20. (c) The stain for INI1 was negative (loss of expression). Immunohistochemical stains were diffusely and strong positive for EMA (d) and partially positive for SMA (e) and GFAP (f).
case_images: SNI-11-195-g002.jpg
case_images: PMC7395541_01_SNI-11-195-g002.jpg
case_images: F2
case_images: The tumor shows areas of necrosis and high levels of mitotic and apoptotic activity [Figure 2a and b]. INI1 was negative (loss of expression) [Figure 2c]. Immunohistochemical stains were diffusely and strong positive for epithelial membrane antigen (EMA) [Figure 2d] and P63, partially positive for smooth muscle antigen (SMA) [Figure 2e], glial fibrillary acidic protein (GFAP) [Figure 2f], B-cell lymphoma 2, and vimentin (VIM), focally positive for pan-KER and KER 8, and negative for OLIG2, S100, desmin, synaptophysin, NEU-N, and chromogranin.