case_images: PMC6059655_01
case_images: CT head showing enlarged right frontal scalp mass. A: axial view non-contrast, B: axial view with contrast, C: Coronal view with contrast.
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case_images: F1
case_images: Because of the hip pain and nodules, he came to the emergency department where a CT scan showed an enlarged right frontal scalp mass that measured about 4 cm (Figure 1).
case_images: MRI showing scalp mass, vasogenic edema, and midline shift. A: Axial view T1 no contrast, B: Axial view T1 with contrast.
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case_images: F2
case_images: MRI also revealed a right frontal scalp mass and extensive vasogenic edema localized to the right frontal lobe with a 5 mm midline shift at the foramen of Monroe (Figure 2).
case_images: Nuclear medicine bone scan with 99mTc-hydroxymethylene diphosphonate (HMDP) and SPECT showed multiple areas of uptake concerning for malignancy. Uptake shown in right posterior iliac bone.
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case_images: F3
case_images: A follow-up nuclear medicine bone scan demonstrated multiple areas of increased uptake concerning for metastasis (Figure 3).
case_images: Histopathologic staining showing monotonous infiltrate composed of small cells with irregular nuclei, condensed chromatin, and inconspicuous nucleoli.
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case_images: F4
case_images: Histopathology of the biopsy showed a diffuse and monotonous infiltrate composed of small cells with irregular nuclei, condensed chromatin and inconspicuous nucleoli (Figure 4).
case_images: Immunohistochemistry showing cells that are CD20 positive and co-express CD10 and Bcl2.
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case_images: F5
case_images: CD20 positive B-cells and co-express CD10 and Bcl-2 but do not express CD3, 5, 23, 43 and cyclin D1 (Figure 5). CD21 was present highlighting a disrupted follicular dendritic cell meshwork.