PMC9398467_01
Brain MRI upon admission and after MTX withdrawal and FDG-PET findings after MTX withdrawal.
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A: Gd-T1WI upon admission showing multiple lesions in the bilateral cerebral hemisphere and basal ganglia.
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B: FLAIR images upon admission showing hyperintensity surrounding lesions.
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C: Gd-T1WI after MTX withdrawal showing no regression.
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D: FDG-PET after MTX withdrawal showing increased FDG uptake in the lesion.
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In gadolinium-enhanced T1-weighted images (Gd-T1WI), brain magnetic resonance imaging (MRI) revealed multiple lesions with heterogeneous enhancement (Fig. 1A). On fluid-attenuated inversion recovery (FLAIR), perifocal edema was also observed (Fig. 1B). One week after MTX discontinuation (Fig. 1C), fluorine-18-fluorodeoxyglucose-positron emission tomography (FDG-PET) revealed uptake in brain lesions without evidence for systemic lesions (Fig. 1D).
The pathological findings of the left parietal lesion.
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A: Hematoxylin and eosin (H&E) staining (original magnification x40) showing lymphocytic cells, some of which show perivascular cuffing.
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B: H&E staining (original magnification x400) showing diffuse and perivascular infiltration of large atypical lymphoid cells.
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C: Immunostaining for CD20 (original magnification x400) demonstrating a positive result.
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D: In
situ hybridization (original magnification x400) showing no evidence of EBER.
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Histopathological examination of the tumor specimen showed proliferation of large atypical lymphoid cells (Fig. 2A-B). These cells expressed CD 20 (Fig. 2C) and CD 10, were partially positive for BCL6 and MUM1, and were negative for CD 5 and CD 3. In situ hybridization of EBV-encoded small RNA (EBER) was negative (Fig. 2D).
Brain MRI findings after 7 cycles of chemotherapy with R-MPV and rdWBRT.
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A and B: Gd-T1WI (A) and FLAIR (B) showing no evidence of lesions.
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She received rdWBRT [23.40 Gy in 1.8-Gy fractions x 13] as consolidation treatment and was discharged from the hospital without disease (Fig. 3).