PMC9256015_01
Sequential magnetic resonance imaging (MRI) at initial diagnosis and before tumor resection.
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T2-weighted MRI images: 8 years before (A), 6 years before (B), 2 years before (C), and immediately before surgery (D). The peritumoral edema showed gradual development concurrent with the slow growth of the tumor.
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The patient was followed up with annual MRI analyses, and the peritumoral edema showed gradual developing concurrently with slow growth of the tumor (Fig. 1).
Diagnostic image examinations before tumor resection.
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A: Plain computed tomography (CT) showed a low-density lesion in the cortical and subcortical areas of the left frontal lobe without bleeding or calcification. B: Post-contrast CT showed peripheral enhancement of the lesion. C: 18F-fluorodeoxyglucose positron emission tomography showed no apparent accumulation in the lesion. D: T1-weighted images showed a hypointense tumor (15 mm in diameter) in the cortex of the left frontal lobe. E: Post-contrast T1-weighted images showed ring enhancement of the tumor. F: Fluid-attenuated inversion recover images showed a hyperintense tumor with surrounding cerebral edema. G, H: Sagittal and coronal views of post-contrast T1-weighted images showed the tumor facing toward the sylvian fissure.
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Plain computed tomography (CT) of the head showed a low-density lesion in the cortical and subcortical areas of the left frontal lobe without bleeding or calcification (Fig. 2A). Post-contrast CT showed peripheral enhancement of the lesion (Fig. 2B). 18F-fluorodeoxyglucose positron emission tomography showed no apparent accumulation in the lesion (Fig. 2C). T1-weighted images showed a hypointense tumor of 15 mm in diameter in the cortex of the left frontal lobe (Fig. 2D). Post-contrast T1-weighted images showed ring enhancement of the tumor (Fig. 2E). Fluid-attenuated inversion recovery images showed a hyperintense tumor with surrounding cerebral edema (Fig. 2F). T1-weighted images indicated that the tumor faced toward the sylvian fissure (Fig. 2G and H).
Macroscopic images of the tumor.
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A: A view of the tumor boundary showed that it occurred in the cortex. B: A view of the tumor showed that it had a brown jelly-like consistency with vascular formations.
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The tumor showed high neovascularization by draining of the red vein, which was hemorrhagic, elastic, and hard (Fig. 3).
Histopathological examination of the resected tumor.
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A: The tumor showed a slightly dilated microvascular core surrounded by many capillary aggregates in the parenchyma of the brain (hematoxylin and eosin staining, original magnification x20). The vascular network was micronodular and had a glomerular-like structure. We found no atypical vascular endothelial cells and no mitosis was observed. B-D: Immunohistochemical analysis showed that the vascular endothelial cells were positive for CD34 (B, CD34 staining, original magnification x20) and were surrounded by smooth muscle actin-positive pericytes (C, smooth muscle actin staining, original magnification x20). D: Ki-67 labeling index showed a cell proliferative potential of 5.8% (Ki-67 staining, original magnification x20).
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Immunohistochemical analysis showed that the vascular endothelial cells were positive for CD34 and were surrounded by smooth muscle actin-positive pericytes (Fig. 4).