UNASSIGNED: Primary CNS lymphoma (PCNSL) and glioblastoma (GBM) both represent frequent intracranial malignancies with differing clinical management. However, distinguishing PCNSL from GBM with conventional MRI can be challenging when atypical imaging features are present. We employed advanced dMRI for noninvasive characterization of the microstructure of PCNSL and differentiation from GBM as the most frequent primary brain malignancy.
UNASSIGNED: Multiple dMRI metrics including Diffusion Tensor Imaging, Neurite Orientation Dispersion and Density Imaging, and Diffusion Microstructure Imaging were extracted from the contrast-enhancing tumor component in 10 PCNSL and 10 age-matched GBM on 3T MRI. Imaging findings were correlated with cell density and axonal markers obtained from histopathology.
UNASSIGNED: We found significantly increased intra-axonal volume fractions (V-intra and intracellular volume fraction) and microFA in PCNSL compared to GBM (all P < .001). In contrast, mean diffusivity (MD), axial diffusivity (aD), and microADC (all P < .001), and also free water fractions (V-CSF and V-ISO) were significantly lower in PCNSL (all P < .01). Receiver-operating characteristic analysis revealed high predictive values regarding the presence of a PCNSL for MD, aD, microADC, V-intra, ICVF, microFA, V-CSF, and V-ISO (area under the curve [AUC] in all >0.840, highest for MD and ICVF with an AUC of 0.960). Comparative histopathology between PCNSL and GBM revealed a significantly increased cell density in PCNSL and the presence of axonal remnants in a higher proportion of samples.
UNASSIGNED: Advanced diffusion imaging enables the characterization of the microstructure of PCNSL and reliably distinguishes PCNSL from GBM. Both imaging and histopathology revealed a relatively increased cell density and a preserved axonal microstructure in PCNSL.

BACKGROUND: This PET/MRI study compared contrast-enhanced MRI, 18F-FACBC-, and 18F-FDG-PET in the detection of primary central nervous system lymphomas (PCNSL) in patients before and after high-dose methotrexate chemotherapy. Three immunocompetent PCNSL patients with diffuse large B-cell lymphoma received dynamic 18F-FACBC- and 18F-FDG-PET/MRI at baseline and response assessment. Lesion detection was defined by clinical evaluation of contrast enhanced T1 MRI (ce-MRI) and visual PET tracer uptake. SUVs and tumor-to-background ratios (TBRs) (for 18F-FACBC and 18F-FDG) and time-activity curves (for 18F-FACBC) were assessed.
RESULTS: At baseline, seven ce-MRI detected lesions were also detected with 18F-FACBC with high SUVs and TBRs (SUVmax:mean, 4.73, TBRmax: mean, 9.32, SUVpeak: mean, 3.21, TBRpeak:mean: 6.30). High TBR values of 18F-FACBC detected lesions were attributed to low SUVbackground. Baseline 18F-FDG detected six lesions with high SUVs (SUVmax: mean, 13.88). In response scans, two lesions were detected with ce-MRI, while only one was detected with 18F-FACBC. The lesion not detected with 18F-FACBC was a small atypical MRI detected lesion, which may indicate no residual disease, as this patient was still in complete remission 12 months after initial diagnosis. No lesions were detected with 18F-FDG in the response scans.
CONCLUSIONS: 18F-FACBC provided high tumor contrast, outperforming 18F-FDG in lesion detection at both baseline and in response assessment. 18F-FACBC may be a useful supplement to ce-MRI in PCNSL detection and response assessment, but further studies are required to validate these findings. Trial registration ClinicalTrials.gov. Registered 15th of June 2017 (Identifier: NCT03188354, https://clinicaltrials.gov/study/NCT03188354 ).

BACKGROUND: A key limitation in treatment initiation in primary central nervous system lymphoma (PCNSL) is the diagnostic delay caused by lack of recognition of a lesion as a possible lymphoma, steroid initiation, and lesion involution, often resulting in an inconclusive biopsy result. We highlight the importance of multiparametric magnetic resonance imaging (MRI), which incorporates diffusion-weighted imaging, dynamic susceptibility contrast-enhanced perfusion-weighted imaging, and proton magnetic resonance spectroscopy in addition to standard MRI sequences in resolving diagnostic uncertainty for PCNSL.
METHODS: At our center, a consecutive series of 10 patients with histology-proven PCNSL (specifically, diffuse large B-cell lymphoma of the central nervous system) underwent multiparametric MRI. We retrospectively analyzed qualitative and semiquantitative parameters and assessed their radiological concordance for this diagnosis.
RESULTS: We noted overall low apparent diffusion coefficient on diffusion-weighted imaging (mean minimum apparent diffusion coefficient of 0.74), high percentage signal recovery on perfusion-weighted imaging (mean 170%), a high choline-to-creatine ratio, and a high-grade lipid peak on proton magnetic resonance spectroscopy giving an appearance of twin towers. Of 10 patients, 9 had MRI findings concordant for PCNSL, defined as at least 3 of 4 parameters being consistent for PCNSL.
CONCLUSIONS: Concordance between these imaging multiparametric modalities could be used as a radiological predictor of PCNSL, reducing diagnostic delays, providing a more accurate biopsy target, and resulting in quicker treatment initiation.

UNASSIGNED: Neurological manifestations are one of the major concerns for patients with human immunodeficiency virus (HIV). The secondary spectrum includes space-occupying lesions (SOL), including tuberculoma, cryptococcosis, candidiasis, toxoplasmosis, primary central nervous system lymphoma (PCNSL), and progressive multifocal leukoencephalopathy (PML).
UNASSIGNED: To assess the neurological manifestations, disease outcome, and their associations with cluster of differentiation 4 (CD4) counts in patients with HIV.
UNASSIGNED: This single-center, prospective, observational study was performed in the Department of General Medicine of a tertiary care institute, over a period of 2 years (January 2017 to December 2018). The study included 150 known or newly diagnosed HIV patients with CNS SOL. The physical examination, laboratory investigations, and imaging were conducted on every patient, and the findings were noted.
UNASSIGNED: The patients mainly presented with hemiparesis (52%), had involvement of the frontal region (38.7%), and were diagnosed with tuberculoma (29.3%). Other diagnoses were toxoplasmosis (22.7%), PML (17.3%), PCNSL (15.3%), brain abscess (10%), and neurocysticercosis (5.3%). Of 150 patients, 136 (90.7%) were survivors, while 14 (9.3%) were non-survivors. The mean CD4 count was significantly less in patients with toxoplasmosis (P < 0.0001) and PCNSL (P = 0.02), and significantly higher in patients with tuberculoma (P < 0.0001) and brain abscess (P = 0.0009) relative to other causes of SOL. Moreover, the mean CD4 count was not significantly associated with survivors and non-survivors (P = 0.28).
UNASSIGNED: In patients with HIV, CD4 count was significantly low in toxoplasmosis and PCNSL, and high in tuberculoma and brain abscess.

UNASSIGNED: The ONO-4059-02 phase 1/2 study showed favorable efficacy and acceptable safety profile of tirabrutinib, a second-generation Bruton\'s tyrosine kinase inhibitor, for relapsed/refractory primary central nervous system lymphoma (PCNSL). Here, we report the long-term efficacy and safety after a 3-year follow-up.
UNASSIGNED: Eligible patients were aged ≥ 20 years with histologically diagnosed PCNSL and KPS of ≥ 70. Patients received oral tirabrutinib once daily at 320 or 480 mg, or 480 mg under fasted conditions.
UNASSIGNED: Between October 19, 2017, and June 13, 2019, 44 patients were enrolled: 33 and 9 had relapsed and refractory, respectively. The 320, 480, and 480 mg fasted groups included 20, 7, and 17 patients, respectively. The median follow-up was 37.1 months. The overall response rate was 63.6% (95% CI: 47.8-77.6) with complete response (CR), unconfirmed CR, and partial response in 9, 7, and 12 patients, respectively. The median duration of response (DOR) was 9.2 months, with a DOR rate of 19.8%; the median progression-free survival (PFS) and median overall survival (OS) were 2.9 months and not reached, respectively, with PFS and OS rates of 13.9% and 56.7%, respectively. Adverse events occurred in 38 patients (86.4%): grade ≥ 3 in 23 (52.3%) including 1 patient with grade 5 events. KPS and quality of life (QoL) scores were well maintained among patients receiving long-term treatment.
UNASSIGNED: The results demonstrated the long-term clinical benefit of tirabrutinib, with deep and durable response in a subset of patients and acceptable safety profile, while KPS and QoL scores were maintained.

Primary central nervous system lymphoma (PCNSL) is a rare and highly aggressive lymphoma entirely localized in the central nervous system or vitreoretinal space. PCNSL generally initially responds to methotrexate-containing chemotherapy regimens, but progressive or relapsing disease is common, and the prognosis is poor for relapsed or refractory (R/R) patients. PCNSL is often characterized by activation of nuclear factor kappa B (NF-κB) due to mutations in the B-cell receptor (BCR) or toll-like receptor (TLR) pathways, as well as immune evasion. Targeted treatments that inhibit key PCNSL mechanisms and pathways are being evaluated; inhibition of Bruton\'s tyrosine kinase (BTK) downstream of BCR activation has demonstrated promising results in treating R/R disease. This review will summarize the evidence and potential for targeted therapeutic agents to improve treatment outcomes in PCNSL. This includes immunotherapeutic and immunomodulatory approaches and inhibitors of the key pathways driving PCNSL, such as aberrant BCR and TLR signaling.

This critique evaluates a letter to the editor discussing prognostic factors in primary central nervous system lymphoma (PCNSL), focusing on C-reactive protein (CRP) levels, prognostic nutritional index (PNI), and lactate dehydrogenase (LDH)-to-lymphocyte ratio. While the letter provides valuable insights, limitations including reliance on a single-center dataset, lack of consideration for potential confounders, insufficient contextualization within existing literature, and limited discussion of clinical implications are identified. Addressing these limitations is crucial for enhancing the relevance and applicability of the findings in PCNSL management.

UNASSIGNED: Primary central nervous system lymphoma(PCNSL) is an aggressive, rare form of Non-Hodgkin lymphoma, characterized by the absence of systemic disease. There are limited data and no strictly defined guidelines for management of PCNSL.
UNASSIGNED: The aim of this study was to report a 10 year experience of PCNSL treatment, to evaluate treatment outcomes and asses Progression Free and Overall Survival of these patients.
UNASSIGNED: Study was conducted on the Haematology Clinic, Clinical center University of Sarajevo, BH, in the period from January 2012.-December 2022. Total sample of 24 patients were enrolled. All have undergone diagnostic surgery. Patients were treated with regimens based on High dose Methotrexate, with/without whole brain radiotherapy as consolidation. Treatment response was captured by imaging techniques. Patients who have relapsed were evaluated with imaging techniques and treated according to Methotrexate-based treatment protocols.
UNASSIGNED: We have captured equal gender distribution. The median age of patients was 59.5 years (range 20-79). Pathohistological analysis confirmed DLBCL diagnosis in 22 patients, T cell lymphoma and anaplastic large cell lymphoma, each in 1 patient. Chemotherapy, chemotherapy combined with WBRT and radiotherapy were given to 5, 18 and 1 patients, respectively. The overall complete response rate (CR) was 87,15%. Those receiving combined modality-treatment had higher CR than those receiving chemotherapy (94,4% versus 60%). Out of 24 patients, 11 of them relapsed. The median time to relapse was 29 months (from 1 to 105). After second line of the treatment, CR was 54,5%, while 45,45% of patients died during the treatment. 4 patients relapsed for the second time with median time to relapse of 9 months (from 2 to 77). 2 year OS rate was 67%, and the median OS rate was 45,9 months. 2 year PFS rate was 31%.
UNASSIGNED: The OS and PFS rates indicate the usage of new drugs and consolidation with autologous stem cell transplantation in patients with PCNSL in order to achieve better treatment outcomes.

Primary Angiitis of the Central Nervous System (PACNS) is a rare disease and its diagnosis is a challenge for several reasons, including the lack of specificity of the main findings highlighted in the current diagnostic criteria. Among the neuroimaging pattern of PACNS, a tumefactive form (t-PACNS) is a rare subtype and its differential diagnosis mainly relies on neuroimaging. Tumor-like mass lesions in the brain are a heterogeneous category including tumors (in particular, primary brain tumors such as glial tumors and lymphoma), inflammatory (e.g., t-PACNS, tumefactive demyelinating lesions, and neurosarcoidosis), and infectious diseases (e.g., neurotoxoplasmosis). In this review, the main features of t-PACNS are addressed and the main differential diagnoses from a neuroimaging perspective (mainly Magnetic Resonance Imaging-MRI-techniques) are described, including conventional and advanced MRI.

OBJECTIVE: Primary central nervous system lymphoma (PCNSL) is a rare malignancy of the central nervous system with high invasiveness. There is little consensus on the treatment of PCNSL. This study retrospectively studied data from PCNSL patients in a single center to summarize treatment experience and explore prognostic factors.
METHODS: Survival curves were drawn using the Kaplan-Meier method and prognostic factors were analyzed using Cox\'s hazards model.
RESULTS: In multivariate analysis, cerebrospinal fluid lactic acid dehydrogenase (CSF LDH; p = 0.005 and p = 0.002), neutrophil to lymphocyte ratio (NLR; p = 0.014 and p = 0.038), and completion of four cycles of induction therapy (p < 0.001and p < 0.001) were significant and independent predictors of overall survival (OS) and progression-free survival (PFS), respectively.
CONCLUSIONS: On the basis of this study, we propose that PCNSL patients should receive early induction therapy with sufficient cycles. Subsequent consolidation therapy can prevent relapses and improve survival. In patients with PCNSL, the independent prognostic factors for OS and PFS were CSF LDH level, NLR, and full cycles of induction therapy.