case_images: PMC11799690_01
case_images: Preoperative computed tomography demonstrating a left parasagittal erosive calvarial lesion; (a) bone window axial image, (b) bone window coronal image, and (c) soft-tissue post-contrast coronal image.
case_images: SNI-16-6-g001.jpg
case_images: PMC11799690_01_SNI-16-6-g001.jpg
case_images: F1
case_images: The mass extended both intracranially and extracranially, measured 8.5 cm x 8.5 cm x 5.5 cm, and crossed the midline, encroaching on the superior sagittal sinus [Figure 1].
case_images: Preoperative magnetic resonance imaging T1-weighted post-contrasted scans (a) coronal, (b) axial, and (c) sagittal cuts showing an avidly enhancing left frontoparietal bony lesion with a dural base over the superior sagittal sinus.
case_images: SNI-16-6-g002.jpg
case_images: PMC11799690_01_SNI-16-6-g002.jpg
case_images: F2
case_images: T1 with heterogeneous enhancement after contrast administration and a mixed isointense and hyperintense mass on T2 [Figure 2]. The mass extended across the midline and inferiorly, resulting in partial compression of the underlying left frontoparietal parenchyma with no associated vasogenic edema.
case_images: Postoperative magnetic resonance imaging T1-weighted post-contrasted scans (a) coronal, (b) axial, and (C) sagittal cuts demonstrating a gross total resection of the calvarial lesion.
case_images: SNI-16-6-g003.jpg
case_images: PMC11799690_01_SNI-16-6-g003.jpg
case_images: F3
case_images: A postoperative MRI confirmed gross total resection of the mass [Figure 3].
case_images: Histological examination of the surgical tissue specimen. (a) The tumor has a trabecular architecture with intervening dilated vascular channels. (b) The tumor cells are polygonal and have irregular nuclei with vesicular chromatin, conspicuous nucleoli, and clear cytoplasm. (c-f) The tumor stains positive for Cam5.2, Arginase, HepPar-1, and Albumin ISH.
case_images: SNI-16-6-g004.jpg
case_images: PMC11799690_01_SNI-16-6-g004.jpg
case_images: F4
case_images: Other markers, namely, epithelial membrane antigen (EMA), progesterone receptor (PR), paired box gene 8 (PAX8), cluster of differentiation 10 (CD10), renal cell carcinoma (RCC), S100, and Melanoma Cocktail staining, yielded negative results, ruling out other metastatic and primary tumor etiologies [Figure 4].