Challenges and prospects in the diagnosis and treatment of primary central nervous system lymphoma

The ghost tumour revisited. Corticosteroids in primary central nervous system lymphoma: diagnostic, prognostic and therapeutic implications

OBJECTIVE

The cytolytic effect of corticosteroids on primary central nervous system lymphoma (PCNSL) has established the clinical dogma of avoiding steroid therapy prior to surgery for diagnostic purposes. However, since steroids are very useful during the initial management of intracranial lesions with vasogenic oedema, it was our aim to determine whether they cause a drawback in the diagnosis and prognosis of PCNSL.

METHODS

A retrospective cohort study of patients diagnosed with PCNSL between 2000 and 2020 in our tertiary neurosurgical centre. Data on steroid administration, surgery type and complications, haematopathological findings and prognostic factors were compiled. A second cohort was used as a control group to compare the ratio of non-diagnostic biopsies; this series comprised patients who underwent stereotactic brain biopsy for any reason between 2019 and 2020.

RESULTS

Forty patients with PCNSL were included in the study, of which 28 (70%) had received steroids before surgery. The use of steroids was more prevalent in patients with poorer performance status at diagnosis. No relevant differences were found in the diagnostic accuracy regardless of steroid exposure (93% under steroids vs 100% without steroids) or type of surgery performed. Furthermore, steroid withdrawal did not seem to augment the diagnostic ratio. The notable diagnostic delay was not influenced by the use of steroids.

CONCLUSIONS

Novel imaging and surgical techniques might obviate the need to withhold corticosteroids from patients suffering from PCNSL prior to biopsy. Moreover, when steroids have been given, tapering them and delaying the surgery might not be justified. This could hold relevant therapeutic implications in the early clinical stages.

Primary large B-cell lymphoma of the central nervous system with positive NMDAR antibody: a case report

Background

N-methyl-D-aspartate receptor (NMDAR) is an ionotropic glutamate (Glu) receptor that is widely expressed in the central nervous system (CNS), mainly in the hippocampus. We present a case in which the patient had atypical clinical manifestations and was positive for anti-NMDAR antibodies.

Case presentation

A 40-year-old male was admitted to the hospital with “dizziness and double vision for 2 months”. At admission, the patient was lethargic, had short-term memory loss, exhibited loss of orientation (time, place, and person) and calculation ability, and had limited left eye abduction. After admission, serum anti- NMDAR antibody was 1:32, and cerebrospinal fluid was 1:1. Magnetic resonance imaging (MRI) revealed diffuse abnormal signals in the bilateral basal ganglia, thalamus, brainstem, hippocampus, and temporal lobe, with patchy and heterogeneous enhancement. A stereotactic brain biopsy was performed, and the pathological results indicated normal brain tissue. Preliminary diagnosis suggested anti-NMDAR antibody encephalitis. The patient was treated with methylprednisolone combined with intravenous gamma globulin; the symptoms were alleviated, and the patient was discharged. Two months later, the patient’s symptoms worsened, and a second stereotactic brain biopsy was performed. The pathological results showed that the patient had primary diffuse large B-cell lymphoma of the CNS, and the patient was transferred to the Department of Hematology and received chemotherapy combined with rituximab. The patient was in stable condition.

Conclusions

When the primary CNS diffuses large B-cell lymphoma is associated with autoimmune encephalitis, it is very easy to be misdiagnosed. The diagnosis should not be based on the pathological examination that was performed in the early stage of the disease. Therefore, in the diagnosis of immune diseases caused by nervous system infections, it is necessary to dynamically observe the evolution of the disease, perform differential diagnoses when necessary, and ultimately improve our understanding of the disease.

Vitreoretinal Lymphoma

Vitreoretinal lymphoma (VRL) is a rare variant of primary central nervous system lymphoma (PCNSL), mostly of diffuse large B cell lymphoma, which affects the retina and/or the vitreous with or without optic nerve involvement. The disease course is aggressive. Up to 90% of the patients develop central nervous system lymphoma within one year. The diagnosis of VRL is challenging due to nonspecific chronic and relapsing uveitis and is made by anterior chamber tab or vitreous aspirate biopsy. There is no established treatment protocol for VRL patients with bilateral involvement without CNS involvement. There are suggestions to use only intravitreal chemotherapy with methotrexate and/or rituximab. Alternatively, systemic high-dose MTX treatment or external beam radiotherapy is used. Further studies are needed to prove and confirm the prophylactic systemic therapy in preventing CNS involvement in limited VRL.

A diagnostic challenge of primary Central nervous system lymphoma: from the eyes to the brain

Background: Being a subtype of primary central nervous system lymphoma (PCNSL), primary vitreoretinal lymphoma (PVRL) is a rare and fatal intraocular malignancy manifesting as blurred vision and floaters, and is usually combined with, or eventually progresses to, central nervous system lesions. The diagnosis of PVRL/PCNSL remains challenging because of the nonspecific clinical features and diagnostic dependency on biopsy.Case presentation: In this paper, we present the clinical, imaging, laboratory, brain biopsy, and vitreous biopsy findings of a 56-year-old immunocompetent woman who presented with blurred vision of the left eye, but which rapidly evolved into lesions of the central nervous system. The dramatic changes on brain imaging and the undiagnostic brain and vitreous biopsy results presented great challenges for the diagnosis. PCNSL was eventually presumed according to comprehensive consideration of the disease progression pattern, the characteristic neuroimaging, and molecular hints.Conclusions: PCNSL is a highly invasive tumor, and timely diagnosis is the key point in clinical practice. However, the requirement for biopsy and the existence of sentinel lesions impedes the diagnosis. Therefore, follow-up and repeated biopsy is always necessary for a definitive diagnosis. This case indicates that a complete evaluation of neuroimaging, ophthalmic testing, cytologic examination of the cerebrospinal fluid, diagnostic vitrectomy, and brain biopsy are essential for diagnosis of PCNSL. Moreover, molecular and cytokine analyses are useful adjuncts to the diagnostic cytology. Of note, the analysis of cytokine levels (IL-10/IL-6) is an important auxiliary diagnostic strategy in the diagnosis of diffuse large B-cell lymphoma.

A Case of Primary Central Nervous System Lymphoma Mimic Neuromyelitis Optica

Primary central nervous system lymphoma (PCNSL) is rare. And the symptoms of PCNSL are atypical, it is extremely easy to be misdiagnosed as other diseases. However, early treatment is crucial which is requesting early diagnosis. We report a case of a 47-year-old man who was initially diagnosed as neuromyelitis optica (NMO) on the basis of clinical findings, slightly high Aquaporin4 (AQP4) (1:10) and high signals of magnetic resonance imaging. Though his symptoms progressively improved after steroid pulse treatment, but worse when steroid was decreased to 40 mg per day. We considered the patient should be diagnosed as PCNSL. After the examination of magnetic resonance spectroscopy (MRS) and positron emission tomography (PET), the results indicated PCNSL was most possible. Therefore we gave him stereotactic biopsy of deep of supratentorial, which showed non-Hodgkin malignant B-cell lymphoma.

Preparation and Characterization of Fe3O4@MTX Magnetic Nanoparticles for Thermochemotherapy of Primary Central Nervous System Lymphoma in vitro and in vivo

Background

Primary central nervous system lymphomas (PCNSL) are extranodal malignant non-Hodgkin lymphomas (NHL) that arise exclusively in central nervous system (CNS). Diffuse large B-cell lymphoma (DLBCL) is the most common histological subtype.

Purpose

To evaluate whether nano drug-loading system-mediated magnetic-targeted thermochemotherapy could produce a better therapeutic effect than single chemotherapy while reducing the use of chemotherapeutic drugs.

Methods

Six groups (control, Fe₃O₄, MTX, Fe₃O₄@MTX, Fe₃O₄ with hyperthermia and Fe₃O₄@MTX with hyperthermia) were set. Tumor cell apoptosis in each treatment group was detected by flow cytometry. Apoptosis-related gene expressions Caspase-3, Bax and Bcl-2 were detected by qPCR and Western blot; intracranial tumor model of PCNSL was established by intracranial injection of OCI-LY18 tumor cells into BALB/c-Nude mice. Magnetic resonance imaging (MRI) was used to monitor tumor progression and H&E staining was used to observe pathological changes of the tumor tissue.

Results

In vitro, compared with chemotherapy alone, apoptosis rate of Fe₃O₄@MTX mediated thermochemotherapy group was significantly increased, and expression of apoptosis-inducing gene Caspase-3 and Bax were significantly upregulated in OCI-LY18 cells, while expression of apoptosis-inhibiting Bcl-2 gene was significantly downregulated. In vivo, MRI showed successful generation of intracranial tumor, and tumor volume was significantly smaller in combined thermochemotherapy group than in single chemotherapy group. H&E staining result of tumor tissues in each group was consistent with MRI; tumor cells were significantly reduced in thermochemotherapy group. Expression of apoptosis-related gene Caspase-3 and Bax were significantly upregulated in tumor tissues, while expression of Bcl-2 gene was significantly downregulated.

Conclusion

These results demonstrated in vivo and in vitro that the combined thermochemotherapy of Fe₃O₄@MTX MNPs was superior to the single MTX chemotherapy with less dosage, which may promote apoptosis of DLBCL cells through the mitochondrial apoptotic pathway and provided a new way for the treatment of PCNSL.