case_images: PMC11152533_01
case_images: Head computed tomography demonstrating a soft-tissue mass originating from the left temporal bone and invading the left posterior cranial fossa. (a) Bone and (b) brain windows.
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case_images: F1
case_images: Head computed tomography (CT) findings revealed a bulky enhancement soft-tissue mass (maximum transverse diameter of 4.2 cm x 3.6 cm) of the left posterior cranial fossa and temporo-occipital region that had eroded the base bone from the skull to the middle and posterior cranial fossa [Figure 1].
case_images: Preoperative brain magnetic resonance imaging showing a lesion located in the left temporal: Petrous and mastoid part invading the left cerebellopontine angle. (a) T1 and (b) T2 weighted. (c) Fluid attenuated inversion recovery image and (d) T2 gradient echo exhibiting peripheral hypointensity, suggesting a high vascularization pattern.
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case_images: F2
case_images: Magnetic resonance imaging (MRI) revealed an irregular, heterogeneous, and lobulated mass in the left posterior cranial fossa and temporo-occipital region, which showed hyperintensity on T1- and T2-weighted images [Figures 2a and b]. Fluid-attenuated inversion recovery imaging presented a hyperintense signal [Figure 2c]. The tumor also exhibited a high vascularization pattern on the T2 gradient echo sequence [Figure 2d].
case_images: Brain magnetic resonance imaging - fluid-attenuated inversion recovery image showing hydrocephalus. (a) There is an enlargement of the third and lateral ventricles. (b) Periventricular white matter hyperintensities suggest interstitial edema due to hydrocephalus.
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case_images: F3
case_images: Meanwhile, the lesion had compressed the fourth ventricle resulting in hydrocephalus [Figure 3].
case_images: Samples from the temporal bone region: (a) Hematoxylin and Eosin (H&E) stain (x200). Neoplasm of a florid papillary arrangement with a dense fibrous core presenting proliferated and congested capillaries and cuboidal to columnar epithelial lining. (b) H&E stain (x400). Epithelial cells have clear or eosinophilic cytoplasm, recovering the papillary structures in a monolayer. (c) Epithelial membrane antigen (EMA) (x400). The cuboidal to columnar epithelial recovering the papillae staining positively for EMA. (d) CD34 (x400). Capillaries are highlighted by CD34 immunopositivity.
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case_images: F4
case_images: Samples from the temporal left bone histologically revealed a neoplasm with a papillary pattern with a dense fibrous core presenting proliferated and congested capillaries and cuboidal to the columnar epithelial lining with clear or eosinophilic cytoplasm [Figures 4a-d]. Immunohistochemistry (IHC) examination showed tumor cells diffusely and strongly positive for keratin (AE1/AE3 and CK7), epithelial membrane antigen [Figure 4c], vimentin (also observed in vascular structures and stromal cells), and chromogranin A and negativity for CK20, S100 protein, glial fibrillary acidic protein, synaptophysin, and desmin. Microvessels were positive for CD34 [Figure 4d], CD31, and smooth muscle actin.
case_images: Head CT 3D image reconstruction using RadiAnt DICOM Viewer Software (Medixant, Poznan, Poland). (a) Posterior view exhibiting the posterior fossa decompression with left extension. It is possible to observe the virtual pathology slide burr hole on the right side. (b) Superior view. (c) Oblique view.
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case_images: F5
case_images: The procedure included a midline incision followed by an autologous pericranium dural augmentation [Figure 5].
case_images: Head and neck angiography. (a) The angiogram revealed a high vascularization area from branches of the occipital artery compatible with the tumor feeding (black arrow). (b) After tumor endovascular embolization, there was a considerable blood flow interruption (red arrow). Asterix represents the tumor area. ECA: External carotid artery, MaxA: Maxillary artery, STA: Superficial temporal artery, OA: Occipital artery.
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case_images: F6
case_images: The angiogram images were processed using the RadiAnt DICOM Viewer Software (Medixant, Poznan, Poland) [Figure 6].
case_images: Follow-up brain magnetic resonance imaging in (a) T1 weighted, (b) T1 contrast enhancement, (c) T2 weighted, (d) fluid-attenuated inversion recovery image, (e) T2 gradient echo, and (f) axial T1-weighted. (a-e) The residual tumor remains unchanged after 8 years of the last surgical procedure. (c-d) Images show cerebellar parenchymal hyperintensity due to late postradiation effects. (f) Ventricles without hydrocephalus are observed.
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case_images: F7
case_images: The mastoid and petrous portions of the tumor remain unchanged [Figure 7].