case_images: PMC10601739_01
case_images: Magnetic resonance imaging (MRI) on admission. Representative axial T1-weighted images (a), T2-weighted images (b), and contrast-enhanced images (c) showed a mass in the intracranial lateral ventricular trigone. The mass was cystic-solid, and most of the mass was enhanced distinctly with multiple round non-enhanced areas inside.
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case_images: F1
case_images: On enhanced scan, most of the mass was enhanced distinctly, while there were multiple round non-enhanced areas of different sizes in the mass (Fig. 1a-c).
case_images: Representative images of hematoxylin-eosin (HE) staining: clear cell RCC metastasis to hemangioblastoma. a The hemangioblastoma region consisting of capillary network and stromal cells with foamy cytoplasm indicated by the arrows (original magnification x400). b Acinar structures composed of clear cells in the hemangioblastoma indicated by the arrows (original magnification x100). c Magnification of the bright cytoplasmic region in b (original magnification x200). d Acinar-like structure of clear cells in the area of metastatic clear cell RCC (original magnification x400).
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case_images: F2
case_images: To sum up, the hematoxylin-eosin staining showed a typical hemangioblastoma (Fig. 2a). There were a few acinar structures composed of clear cells scattered in the hemangioblastoma, without mitotic and necrosis activity (Fig. 2b-d).
case_images: Representative images of immunohistochemical (IHC) staining: clear cell RCC metastasis to hemangioblastoma. a, b The reactive capillary networks of hemangioblastoma, which was cell membrane-positive for CD34 (a) and cytoplasmic-positive for F8 (b). c The stromal cells of hemangioblastoma were nuclear-positive for NSE focally. d The nonspecific staining of inhibin A in stromal cells of hemangioblastoma. e, f Keratin and EMA, diffuse cell membrane-positive in the epithelial component. g Vimentin showed the negative clear cell RCC component surrounded by diffuse strongly cytoplasmic-positive capillary networks. h-j The clear cell RCC component, which was cell membrane-positive for CD10 (h) and CAIX (i) and nuclear-positive for PAX8 (j). The original magnification of the images was x200, except for c and d where it was x400.
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case_images: F3
case_images: The immunohistochemical staining showed that the reactive vascular components were positive for CD34 and factor VIII-related antigen (F8) (Fig. 3a, b). The stromal cells had focal staining for NSE (Fig. 3c). Unfortunately, the inhibin A was negative with nonspecific staining of only a few cells (Fig. 3d). CD10, CAIX, and PAX8 (Fig. 3e, f, h-j) but showed negative staining for CD34, F8 (Fig. 3a, b), and vimentin (Fig. 3g). Combined with the histological morphology and immunohistochemical staining, the case report was diagnosed as a collision tumor of hemangioblastoma and metastatic clear cell RCC.