case_images: PMC10730807_01
case_images: Brain magnetic resonance imaging of preoperation shows an enhanced extraaxial mass-like lesion with adjacent subgaleal tissue thickening/enhancement, bony destruction in the right frontal area, dural thickening/enhancement, and leptomeningeal enhancement along the right cerebral convexity. (A) T2-axial, (B) precontrast T1-axial, and (C) postcontrast T1-axial images.
case_images: jrd-31-1-54-f1.jpg
case_images: PMC10730807_01_jrd-31-1-54-f1.jpg
case_images: F1
case_images: Dural thickening with enhancement and leptomeningeal enhancement along the right cerebral convexity are shown (Figure 1).
case_images: Histopathologic findings of tissue biopsy from scalp lesion. (A) Storiform fibrosis (yellow arrow) with destruction of the skull on H&E stain (x100). (B) Dense fibrosis and infiltration of inflammatory cells including lymphocytes, plasma cells and histiocytes on H&E stain (x200). (C) Increased immunoglobulin G4-positive cells (up to 68/high power field on immunoglobulin G4 immunohistochemistry stain) (x200).
case_images: jrd-31-1-54-f2.jpg
case_images: PMC10730807_01_jrd-31-1-54-f2.jpg
case_images: F2
case_images: Postoperative histopathology revealed HP with storiform fibrosis, destruction of the skull, and marked infiltrations of lymphocytes, plasma cells, and histiocytes without granulomatous inflammation (Figure 2A and 2B). Immunohistochemistry showed that IgG4-positive cells increased to 68 in a high power field (HPF) with IgG4/IgG ratio of 22.7%, while negative for epithelial membrane antigen and pan-cytokeratin with nonspecific for vimentin was noted (Figure 2C).
case_images: Serial changes of serum acute phase reactants according to time. (A) Erythrocyte sedimentation rate (mm/h); (B) C-reactive protein (mg/dL). POD: postoperation day.
case_images: jrd-31-1-54-f3.jpg
case_images: PMC10730807_01_jrd-31-1-54-f3.jpg
case_images: F3
case_images: Although naproxen and antibiotics were administered after the surgery, ESR and CRP increased to 21 mm/h and 3.99 mg/dL, respectively, on the day of consultation (POD 19; Figure 3). Serum levels of ESR and CRP decreased dramatically just one day after starting prednisolone (0.5 mg/kg), which normalized three days after the steroid therapy (Figure 3).