PMC8178116_01
Changes in brain magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT). a A mass lesion in the right temporal lobe was detected on brain MRI (T1-weighted) at the time of diagnosis of primary central nervous system lymphoma (PCNSL). b No abnormal uptake on PET-CT was detected at the time of diagnosis. After six cycles of high-dose methotrexate (HD-MTX) therapy, there were no visible masses on brain MRI (c) and no abnormal findings were observed on PET-CT (d). e Several masses were seen in the right temporal and frontal lobes on brain MRI (T1-weighted) at the time of recurrence. f After six cycles of HD-MTX therapy, there were no visible masses on MRI. g Abnormal 18F-fluorodeoxyglucose (FDG) uptake in several bone lesions, including the thoracic vertebrae, coccyx, and femur, was detected on PET-CT. h The maximum standardized uptake value of the coccyx was 10.52, and biopsy of this lesion was performed. i Abnormal FDG uptake was observed in the liver (maximum standardized uptake value [SUV max] = 7.15), spleen (SUV max = 14.23), bilateral lung fields, and bone marrow at the time of diagnosis of intravascular large B-cell lymphoma. j After six cycles of DA-EPOCH-R (dose-adjusted etoposide, vincristine, doxorubicin, cyclophosphamide, and prednisone and rituximab) therapy, PET-CT showed complete metabolic remission.
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Brain magnetic resonance imaging (MRI) revealed a mass in the right temporal lobe (Fig. 1a). Positron emission tomography- computed tomography (PET-CT) showed no abnormal uptake of 18F-fluorodeoxyglucose (FDG) (Fig. 1b). After the administration of six cycles of high-dose methotrexate (HD-MTX) (3.5 g/m2), complete remission was achieved (Fig. 1c, d). Brain MRI showed new masses in the right temporal and frontal lobes (Fig. 1e). HD-MTX therapy, there were no visible masses on MRI (Fig. 1f). However, PET-CT showed abnormal FDG uptake in several bone lesions, including the thoracic vertebrae, coccyx, and femur (Fig. 1g). Biopsy of the coccyx, which had the maximum standardized uptake value (SUV) (10.52) (Fig. 1h) among the lesions observed on PET-CT, was performed. PET-CT showed prominent hepatosplenomegaly with abnormal FDG uptake (Fig. 1i). After six cycles of DA-EPOCH-R therapy, PET-CT showed complete metabolic remission (Fig. 1j).
a Pathological findings of the cerebrum reveals proliferative tumor cells diffusely infiltrating the central nervous system (hematoxylin and eosin staining). Pathological findings of random skin biopsy. b The lumens of the small blood vessels were occupied by large lymphoid cells (hematoxylin and eosin staining), which were positive for CD5 (c) and CD20 (d).
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However, after she received 21 Gy of radiotherapy, the final histological diagnosis was PCNSL with diffuse infiltration of large lymphoid cells in the cerebrum, particularly with perivascular infiltration (Fig. 2a). A random skin biopsy was performed, and all biopsied specimens demonstrated obstruction of the small vessels by large lymphoid cells (Fig. 2b-d).