case_images: PMC11143865_01
case_images: Axial (a) and coronal (b) views of computed tomography of petrous temporal bones showing an erosive mass of the right external auditory canal (EAC), extending into the middle ear with erosion of the anterior and inferior EAC walls.
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case_images: PMC11143865_01_10.1177_2050313X241258155-fig1.jpg
case_images: fig1-2050313X241258155
case_images: There was no evidence of ossicular chain disruption, but significant bony erosion of the tympanic bone was observed (Figure 1).
case_images: Histological findings: (a) and (b). Proliferation of clusters of cubocylindrical cells with densely atypical nuclei within a fibro-inflammatory stroma (blue asterisk). This proliferation elevates a surface squamous epithelium lining of the EAC (red asterisk) (HE x400). (c) Positive immunostaining for Thyroid transcription factor-1 (x400). (d) Positive immunostaining for cytokeratin 7 (x400).
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case_images: PMC11143865_01_10.1177_2050313X241258155-fig2.jpg
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case_images: Thyroid transcription factor-1 (TTF1), while staining for p63 protein and Trans-acting T-cell-specific transcription factor GATA-3 was negative. This ruled out a urothelial origin for this metastatic lesion (Figure 2).
case_images: Sagittal (a) and axial (b) views of contrast-enhanced thoracic computed tomography (CT) revealing a massive tumor mass in the apicodorsal region of the right upper lobe of the lung. Axial (c) view of contrastenhanced cerebral CT revealing a well-defined, homogeneous process that avidly enhances, surrounded by a prelesional hypodensity zone, in direct contact with the left side of the cerebellar tent (red arrow).
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case_images: PMC11143865_01_10.1177_2050313X241258155-fig3.jpg
case_images: fig3-2050313X241258155
case_images: Additionally, a few centimeter-sized lymph nodes were observed in the right pulmonary hilar and peritracheal regions (Figure 3(a) and (b)). An enhanced brain CT scan exhibited a well-defined, homogeneous expansive process in direct contact with the left side of the cerebellar tent, suggestive of a secondary brain localization (Figure 3(c)).