Primary CNS lymphoma

Impact of Postoperative Chemotherapy on Survival in Patients with Primary Central Nervous System Lymphoma: A Study Based on the SEER Database

Aims/Background We aimed to investigate the impact of postoperative chemotherapy (POCT) on survival in patients with primary central nervous system lymphoma (PCNSL) using data from the Surveillance, Epidemiology, and End Results (SEER) database. Methods This study included 786 PCNSL patients, of which 605 received chemotherapy after surgery, and 181 did not. Data from the SEER registry database (2007-2020) were used to analyze PCNSL. Baseline information, including age, sex, race, marital status, primary tumour site, histological type, summary stage, surgical procedures, chemotherapy, and radiotherapy, was analyzed. Propensity Score Matching (PSM) (1:1) was employed to balance the effects of confounding variables between the two groups. Subsequently, Cox regression and bidirectional stepwise regression were used to identify independent prognostic factors. Kaplan-Meier (K-M) survival curves were constructed to assess the impact of POCT on patient prognosis. Additionally, two cases of PCNSL with typical magnetic resonance imaging appearances were presented. Results Multivariate Cox regression results revealed that age older than 60 years (hazard ratio [HR] = 1.786; 95% confidence interval [CI]: 1.272-2.509; p = 0.001) and absence of POCT (HR = 2.841; 95% CI: 2.159-3.738; p < 0.001) were independent prognostic risk factors, while primary tumour locations in the meninges (HR = 0.136; 95% CI: 0.032-0.569; p = 0.006) and other nervous system regions (HR = 0.552; 95% CI: 0.326-0.936; p = 0.027), as well as histological morphologies such as diffuse large B-cell lymphoma (HR = 0.233; 95% CI: 0.128-0.425; p < 0.001) and non-Hodgkin lymphoma (HR = 0.559; 95% CI: 0.356-0.876; p = 0.011), were associated with favourable patient outcomes. K-M curves demonstrated that the group undergoing POCT had a significantly more favourable prognosis compared to the non-POCT group, before (HR = 0.454; 95% CI: 0.343-0.600; p < 0.0001) or after PSM (HR = 0.580; 95% CI: 0.431-0.780; p < 0.0001). For patients with PCNSL, those with tumours located in the infratentorial region (HR = 0.231; 95% CI: 0.078-0.682; p = 0.046), supratentorial region (HR = 0.250; 95% CI: 0.163-0.383; p < 0.0001), overlapping brain regions (HR = 0.201; 95% CI: 0.056-0.727; p = 0.0058), and those who underwent biopsy (HR = 0.740; 95% CI: 0.463-1.182; p = 0.003), subtotal resection (STR) (HR = 0.490; 95% CI: 0.265-0.906; p = 0.0064), or gross total resection (GTR) (HR = 0.613; 95% CI: 0.292-1.287; p = 0.0003) had better prognoses in the postoperative chemotherapy group compared to the non-chemotherapy group. Conclusion POCT significantly improves the prognosis of PCNSL patients and identifies the characteristics of the benefiting population. This information aids clinical practitioners in designing personalized treatment plans for individuals and advancing precise treatment.

Survival outcomes and treatment experience of 124 patients with primary central nervous system lymphoma

PURPOSE

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.

CONCLUSION

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.

How does deep learning/machine learning perform in comparison to radiologists in distinguishing glioblastomas (or grade IV astrocytomas) from primary CNS lymphomas?: a meta-analysis and systematic review

BACKGROUND

Several studies have been published comparing deep learning (DL)/machine learning (ML) to radiologists in differentiating PCNSLs from GBMs with equivocal results. We aimed to perform this meta-analysis to evaluate the diagnostic accuracy of ML/DL versus radiologists in classifying PCNSL versus GBM using MRI.

METHODOLOGY

The study was performed in accordance with PRISMA guidelines. Data was extracted and interpreted by two researchers with 12 and 23 years' experience, respectively, and QUADAS-2 tool was used for quality and risk-bias assessment. We constructed contingency tables to derive sensitivity, specificity accuracy, summary receiver operating characteristic (SROC) curve, and the area under the curve (AUC).

RESULTS

Our search identified 11 studies, of which 8 satisfied our inclusion criteria and restricted the analysis in each study to reporting the model showing highest accuracy, with a total sample size of 1159 patients. The random effects model showed a pooled sensitivity of 0.89 [95% CI:0.84-0.92] for ML and 0.82 [95% CI:0.76-0.87] for radiologists. Pooled specificity was 0.88 [95% CI: 0.84-0.91] for ML and 0.90 [95% CI: 0.81-0.95] for radiologists. Pooled accuracy was 0.88 [95% CI: 0.86-0.90] for ML and 0.86 [95% CI: 0.78-0.91] for radiologists. Pooled AUC of ML was 0.94 [95% CI:0.92-0.96]and for radiologists, it was 0.90 [95% CI: 0.84-0.93].

CONCLUSIONS

MRI-based ML/DL techniques can complement radiologists to improve the accuracy of classifying GBMs from PCNSL, possibly reduce the need for a biopsy, and avoid any unwanted neurosurgical resection of a PCNSL.

Balanced transformer: efficient classification of glioblastoma and primary central nervous system lymphoma

Objective.Primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM) are malignant primary brain tumors with different biological characteristics. Great differences exist between the treatment strategies of PCNSL and GBM. Thus, accurately distinguishing between PCNSL and GBM before surgery is very important for guiding neurosurgery. At present, the spinal fluid of patients is commonly extracted to find tumor markers for diagnosis. However, this method not only causes secondary injury to patients, but also easily delays treatment. Although diagnosis using radiology images is non-invasive, the morphological features and texture features of the two in magnetic resonance imaging (MRI) are quite similar, making distinction with human eyes and image diagnosis very difficult. In order to solve the problem of insufficient number of samples and sample imbalance, we used data augmentation and balanced sample sampling methods. Conventional Transformer networks use patch segmentation operations to divide images into small patches, but the lack of communication between patches leads to unbalanced data layers.Approach.To address this problem, we propose a balanced patch embedding approach that extracts high-level semantic information by reducing the feature dimensionality and maintaining the geometric variation invariance of the features. This approach balances the interactions between the information and improves the representativeness of the data. To further address the imbalance problem, the balanced patch partition method is proposed to increase the receptive field by sampling the four corners of the sliding window and introducing a linear encoding component without increasing the computational effort, and designed a new balanced loss function.Main results.Benefiting from the overall balance design, we conducted an experiment using Balanced Transformer and obtained an accuracy of 99.89%, sensitivity of 99.74%, specificity of 99.73% and AUC of 99.19%, which is far higher than the previous results (accuracy of 89.6% ∼ 96.8%, sensitivity of 74.3% ∼ 91.3%, specificity of 88.9% ∼ 96.02% and AUC of 87.8% ∼ 94.9%).Significance.This study can accurately distinguish PCNSL and GBM before surgery. Because GBM is a common type of malignant tumor, the 1% improvement in accuracy has saved many patients and reduced treatment times considerably. Thus, it can provide doctors with a good basis for auxiliary diagnosis.

Genomic Profiling of Primary Diffuse Large B-Cell Lymphoma of the Central Nervous System Suggests Novel Potential Therapeutic Targets

Primary diffuse large B-cell lymphoma of the primary central nervous system (CNS-DLBCL) is an aggressive disease, with dismal prognosis despite the use of high-dose methotrexate-based polychemotherapy. Our study aimed to expand the biologic profiles of CNS-DLBCL and to correlate them with clinical/imaging findings to gain diagnostic insight and possibly identify new therapeutic targets. We selected 61 CNS-DLBCL whose formalin-fixed paraffin-embedded samples were available at first diagnosis. These were investigated by immunohistochemistry, cMYC rearrangements were explored by fluorescence in situ hybridization, and CNS-DLBCL mutated genes were evaluated by next-generation sequencing. CD10, BCL6, and IRF4 were observed in 16%, 83.6%, and 93% of cases, respectively. As typical of CNS lymphoma, 10 (16.4%) of 61 cases were classified as germinal center (GCB) type and 51 (83.6%) of 61 as non-germinal center (non-GCB) type according to the Hans algorithm. Double-expression status for BCL2 and cMYC was detected in 36 (59%) of 61 cases whereas 25 (41%) of 61 were non-DE. Rearrangement of the cMYC gene was detected in 2 cases, associated with BCL6 translocation only in 1 case MYD88, PIM1, CD79B, and TP53 were mutated in 54.5%, 53.5%, 30.2%, and 18.4% cases, respectively. Novel mutations not previously reported in CNS-DLBCL were found: AIP in 23.1%, PI3KCA in 15%, NOTCH1 in 11.4%, GNAS in 8.1%, CASP8 in 7.9%, EGFR in 6.4%, PTEN in 5.1, and KRAS in 2.6% of cases. Survival was significantly longer for patients with mutated MYD88 (8.7 months vs 1.7 months; log-rank test = 5.43; P = .020) and for patients with mutated CD79B (10.8 months vs 2.5 months; log-rank test = 4.64; P = .031). MYD88 and CD79B predicted a longer survival in patients affected by CNS-DLBCL. Notably, we identified novel mutations that enrich the mutational landscape of CNS-DLBCL, suggest a role of PTEN-PI3K-AKT and receptor tyrosine kinase-RAS-mitogen-activated protein kinase signaling in a subset of CNS-DLBCL, and provide new potential therapeutic targets.

Primary Dural Acute Lymphoblastic Leukaemia/Lymphoma Masquerading Meningioma: Report of a Case and Review of Literature

Acute lymphoblastic leukaemia/lymphoma (ALL) is a systemic disease which primarily involves bone marrow or lymphoid organs. Extranodal presentation of ALL is uncommon, and ALL presenting as a dural mass is exceedingly rare. Here we present a case of primary dural B-cell ALL which was preoperatively diagnosed as meningioma on clinico-radiological grounds. A 27-year-old female patient presented with left hemicranial headache for one month's duration along with progressive vision loss of in both eye and altered behaviour. Contrast enhanced magnetic resonance imaging (CE-MRI) suggest dural based mass with dural tail sign. Histopathological examination of the resected specimen revealed B-cell ALL. Further systemic investigations didn't suggest any peripheral blood, bone marrow or lymph node involvement. To the best of our knowledge, only two cases of primary dural ALL have been reported in the literature so far. This report highlights the diagnostic difficulty in extramedullary precursor lymphoid neoplasm.

Atypical primary central nervous system lymphoma and glioblastoma: multiparametric differentiation based on non-enhancing volume, apparent diffusion coefficient, and arterial spin labeling

OBJECTIVES

To evaluate the multiparametric diagnostic performance with non-enhancing tumor volume, apparent diffusion coefficient (ADC), and arterial spin labeling (ASL) to differentiate between atypical primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM).

METHODS

One hundred and fifty-eight patients with pathologically confirmed typical PCNSL (n = 59), atypical PCNSL (hemorrhage, necrosis, or heterogeneous contrast enhancement, n = 29), and GBM (n = 70) were selected. Relative minimum ADC (rADCmin), mean (rADCmean), maximum (rADCmax), and rADCmax-min (rADCdif) were obtained by standardization of the contralateral white matter. Maximum cerebral blood flow (CBFmax) was obtained according to the ASL-CBF map. The regions of interests (ROIs) were manually delineated on the inner side of the tumor to further generate a 3D-ROI and obtain the non-enhancing tumor (nET) volume. The area under the curve (AUC) was used to evaluate the diagnostic performance.

RESULTS

Atypical PCNSLs showed significantly lower rADCmax, rADCmean, and rADCdif than that of GBMs. GBMs showed significantly higher CBFmax and nET volume ratios than that of atypical PCNSLs. Combined three-variable models with rADCmean, CBFmax, and nET volume ratio were superior to one- and two-variable models. The AUC of the three-variable model was 0.96, and the sensitivity and specificity were 90% and 96.55%, respectively.

CONCLUSION

The combined evaluation of rADCmean, CBFmax, and nET volume allowed for reliable differentiation between atypical PCNSL and GBM.

KEY POINTS

• Atypical PCNSL is easily misdiagnosed as glioblastoma, which leads to unnecessary surgical resection. • The nET volume, ADC, and ASL-derived parameter (CBF) were lower for atypical PCNSL than that for glioblastoma. • The combination of multiple parameters performed well (AUC = 0.96) in the discrimination between atypical PCNSL and glioblastoma.

Multiple and recurrent intracranial pseudolymphoma mimicking multiple skull base meningioma, a case report

INTRODUCTION AND IMPORTANCE

Primary central nervous system (CNS) lymphomas (PCNSLs) comprise a heterogeneous subset of intracranial disorders, predominantly of the intraparenchymal high-grade non-Hodgkin's lymphoma. Intracranial pseudolymphoma represents an exceedingly rare entity; as few as 3 reports in the English literature. We describe the first multiple large intracranial pseudolymphomata leading to increased intracranial pressure, visual loss, and recurrence during a short while. It also represents the first report of intracranial pseudolymphoma presented as a skull base tumor.

CASE PRESENTATION

We describe a 67-year-old female suffering from left-sided loss of visual acuity, headache, nausea, vomiting, and improper balance. Axial brain computed tomography (CT) scan revealed an isodense anterior interhemispheric mass lesion with surrounding edema in both frontal lobes. T1 and T2 weighted magnetic resonance imaging (MRI) and T1 weighted with gadolinium injection revealed two extra-axial isointense dural-based mass lesions with homogenous enhancement compressing both frontal lobes. The morphologic findings favored B cell pseudolymphoma and meningeal B cell lymphoid hyperplasia. One year later, she developed headaches, disorientation, and progressive meaningless speech lasting 2 months. Subsequent MRI demonstrated the rapid growth of the lesion of the lesser sphenoid wing and recurrence of the lesion at the same site of surgery, thereby undergoing revision surgery in which both tumors were maximally resected using a pterional approach.

CLINICAL DISCUSSION

Intracranial pseudolymphoma remains exceedingly rare, and despite its benign cellular nature, it may proliferate and recur quickly.

CONCLUSION

Intracranial pseudolymphoma should always be considered a rare but potentially differential diagnosis leading to the intraventricular lesion.

Primary Large B-Cell Lymphoma of Immune-Privileged Sites of the Cerebellum: A Case Series and Review of the Literature

Primary large B-cell lymphoma of immune-privileged sites (IP-LBCL) is a rare malignant hematological neoplasm. Involvement of the cerebellum is even rarer and its diagnosis is often difficult to make due to its non-specific clinical and radiological presentation.

METHODS

We reported 3 cases of cerebellar IP-LBCL followed at our hospital and reviewed the medical literature to unravel the peculiarities of this poorly studied entity.

OUTCOMES

Analyzing our cases and reviewing the literature, we could collect and study 26 cases of cerebellar IP-LBCL. To the best of our knowledge, this is the largest cohort of such patients currently published.

CONCLUSION

Cerebellar IP-LBCL presents more often in adult females with cerebellum-related focal neurological signs such as ataxia, headache, and nausea. Histological confirmation is mandatory for a correct diagnosis and treatment and all cases feature diffuse large B-cell lymphoma histopathology. Compared to other encephalic IP-LBCL, cerebellar cases seem to include a higher number of cases with germinal center B-cell phenotype and better survival. These differences may be related to a different immune microenvironment and especially immunoregulation that distinguishes the cerebellum from other areas of the CNS.

Surgical resection versus biopsy in the treatment of primary central nervous system lymphoma: a systematic review and meta-analysis

PURPOSE

Despite the improvement in treatment and prognosis of primary central nervous system lymphoma (PCNSL) over the last decades, the 5-year survival rate is approximately 30%; thus, new therapeutic approaches are needed to improve patient survival. The study's aim was to evaluate the role of surgical resection of PCNSL.

METHODS

Primary outcomes were the overall survival (OS) and progression-free survival (PFS) of patients with PCNSL who underwent surgical resection versus biopsy alone. The meta-analysis was conducted to calculate pooled hazard ratios (HRs) under a random-effects model for the time-to-event variables. The odds ratios (ORs) were calculated for binary, secondary outcome parameters.

RESULTS

Seven studies (n = 1046) were included. We found that surgical resection was associated with significantly better OS (HR 0.63 [95% CI 0.51-0.77]) when compared with biopsy. PFS was also significantly improved (HR 0.64 [95% CI 0.49-0.85]) in patients who underwent resection compared with those who underwent biopsy. The heterogeneity for OS and PFS was low (I2 = 7% and 24%, respectively). We also found that patients who underwent biopsy more often had multiple (OR 0.38 [95% CI 0.19-0.79]) or deep-seated (OR 0.20 [95% CI 0.12-0.34]) lesions compared with those who underwent surgical resection. There were no significant differences in chemotherapy or radiotherapy use or the occurrence of postoperative complications between the two groups.

CONCLUSION

In selected patients, surgical resection of PCNSL is associated with significantly better overall survival and progression-free survival compared with biopsy alone.

Primary central nervous system lymphoma of the tectal plate in adult

Background:

Primary central nervous system lymphoma (PCNSL) originating in the brainstem is uncommon. In particular, PCNSL confined to the tectal plate in adults has never been reported in the past. The case of a 53-year-old man who was diagnosed with PCNSL in the tectal plate is reported.

Case Description:

The patient was referred to our hospital with a 1-month history of disorientation and magnetic resonance imaging showed hydrocephalus with an enhancing lesion in the tectum. Preoperative blood tests showed a high serum soluble interleukin-2 receptor level of 624 U/ml. Through a single burr hole, endoscopic third ventriculostomy and biopsy of the lesion were simultaneously performed with a flexible endoscope. The histological examination confirmed diffuse large B-cell lymphoma. The patient underwent chemotherapy and radiotherapy.

Conclusion:

Malignant lymphoma of the tectum may occur in adults. By measuring the soluble interleukin-2 level preoperatively, it was possible to include malignant lymphoma in the differential diagnosis. In addition, the use of a neuroendoscope permits biopsy and hydrocephalus treatment to be performed simultaneously.

Cerebellar primary central nervous system lymphoma: Case series report

INTRODUCTION AND IMPORTANCE

Primary central nervous system lymphoma (PCNSL) is a rare cranial malignant haematological tumour. PCNSL in the cerebellar region is less common than PCNSL in other encephalic regions. A diagnosis of cerebellar PCNSL is relatively difficult to make due to its diverse imaging manifestations. The aim of this case series report is to determine whether surgery could be used to confirm the diagnosis of cerebellar PCNSL and the effect of surgical treatment.

METHODS

We report 3 cases of cerebellar PCNSL that underwent neuronavigation microsurgery under general anaesthesia. The operation was performed by author 3 and author 5. One patient underwent left lateral ventricular drainage on the fourth and tenth days after the operation due to postoperative obstructive hydrocephalus. All patients received chemotherapy or radiotherapy after histological confirmation.

OUTCOMES

All patients' tumours were completely removed. One patient developed obstructive hydrocephalus twice during the perioperative period after the operation, was given drainage, and then recovered from the hospital. The other two patients recovered and were discharged smoothly without complications. One patient died 9 months after the operation, and the other two patients survived. The prognosis of 3 patients was related to tumour size and timely follow-up chemo-radiation therapy.

CONCLUSION

The histology of all patients showed diffuse large B-cell lymphoma (GCB phenotype). Suspicious cerebellar PCNSL patients should undergo surgery to confirm the diagnosis, followed by radiotherapy and chemotherapy.

Clinical Impact of the Histopathological Index and Neuroimaging Features Status in Primary Central Nervous System Diffuse Large B-Cell Lymphoma: A Single-Center Retrospective Analysis of 51 Cases

Primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL) is an uncommon non-Hodgkin lymphoma subtype, and its clinical and pathological characteristics remain unclear. PCNS-DLBCL patient data were retrospectively evaluated to determine clinical and pathological characteristics and prognostic factors. Furthermore, prognoses were calculated by Kaplan–Meier and Cox regression models based on clinical observations. In total, 51 immunocompetent patients were enrolled. The median age was 55 (range, 16–82) years, and the male-to-female ratio was 3:2. Headache (n = 19; 37%) and the frontal lobe (n = 16; 31%) were the most common presenting symptom and location, respectively. The median follow-up was 33 (range, 3–86) months, and the median overall survival (OS) and progression-free survival (PFS) were 18 months [95% confidence interval (CI), 21.2–34.2] and 15 months (95% CI, 16.9–28.7), respectively. Ki-67, cluster of differentiation-3, and deep brain involvement were independent prognostic markers. Moreover, multifocal lesions and deep brain involvement were unfavorable independent prognostic markers for PFS. This study indicates that targeted drug development for adverse prognostic factors is possible and provides guidance for clinical treatment decision-making.

CNS Lymphoma: Clinical Pearls and Management Considerations

Primary CNS lymphoma presents unique challenges for the clinician. New evidence has emerged regarding the appropriate workup, management considerations, and treatment. In this paper, we highlight the clinical presentations, disease prognosis, and management considerations. We place specific emphasis on the decision tree for immunocompetent and immunocompromised. The key imaging characteristics are discussed. Once biopsy prove lymphoma, important management considerations are addressed. We highlight need for follow up and role for surgery verse radiation. Finally, we present emerging treatment options and pre-clinical work that will be making its way through the pipeline. This up-to-date review will serve as a key learning tool for clinicians and researchers.

3D pseudo-continuous arterial spin labeling-MRI (3D PCASL-MRI) in the differential diagnosis between glioblastomas and primary central nervous system lymphomas

PURPOSE

The aim of the study was to compare the parameters of blood flow in glioblastomas and primary central nervous system lymphomas (PCNSLs), measured by pseudo-continuous arterial spin labeling MRI (3D PCASL), and to determine the informativeness of this method in the differential diagnosis between these lesions.

METHODS

The study included MRI data of 139 patients with PCNSL (n = 21) and glioblastomas (n = 118), performed in the Burdenko Neurosurgical Center. No patients received chemotherapy, hormone therapy, or radiation therapy prior to MRI. On the 3D PCASL perfusion map, the absolute and normalized values of tumor blood flow were calculated in the glioblastoma and PCNSL groups (maxTBFmean and nTBF).

RESULTS

MaxTBFmean and nTBF in the glioblastoma group were significantly higher than those in the PCNSL group: 168.9 ml/100 g/min versus 65.6 and 9.3 versus 3.7, respectively (p < 0.001). Arterial spin labeling perfusion had high sensitivity (86% for maxTBFmean, 95% for nTBF) and specificity (77% for maxTBFmean, 73% for nTBF) in the differential diagnosis between PCNSL and glioblastomas. Blood flow thresholds were 98.9 ml/100 g/min using absolute blood flow values and 6.1 using normalized values, AUC > 0.88.

CONCLUSION

The inclusion of 3D PCASL in the standard MRI protocol can increase the specificity of the differential diagnosis between glioblastomas and PCNSL.

A Case of Primary Leptomeningeal Lymphoma Presenting with Hydrocephalus Characterized by Disproportionately Large Fourth Ventricle

Primary leptomeningeal malignant lymphoma (PLML) is a rare variant of primary central nerve system malignant lymphoma (PCNSL) which is restricted to leptomeninges. The lesions of PLML can often be detected as abnormal enhancement on the surface of central nervous system or the ventricular wall on magnetic resonance imaging (MRIs). Cerebrospinal fluid (CSF) evaluation together with such MRI findings provides the definitive diagnosis of PLML. Here, we present a 45-year-old female case of PLML in which hydrocephalus with disproportionately large fourth ventricle was observed at presentation with gait instability. Head MRI revealed no abnormal enhancement and CSF cytology was negative, leaving the cause of hydrocephalus undetermined. Endoscopic third ventriculostomy (ETV) was effectively performed for hydrocephalus and her symptoms disappeared. Nearly 2 years later, she was brought to emergent room due to unconsciousness with the recurrence of hydrocephalus. MRI showed expanded fourth ventricle and abnormal enhancement on the ventricular wall. The endoscopic surgery for improving CSF flow was successful and inflammatory change was endoscopically observed on the ventricular wall involving aqueduct. Pathological diagnosis of the specimen from the ventricular wall proved B-cell lymphoma. Because neither brain parenchymal masses nor systemic tumors were identified, she was diagnosed with PLML and treated by high-dose methotrexate. She was in a stable state 2 years after the diagnosis of PLML. We report and discuss the characteristics of this case.

Diagnosis and management of primary central nervous system lymphoma: a Consensus Practice Statement from the Australasian Lymphoma Alliance

Primary central nervous system lymphoma is a clinicopathological disease entity that accounts for 1 % of all non-Hodgkin lymphoma (NHL). Advanced patient age, adverse disease biology and complexities of diagnosis and treatment render outcomes markedly inferior to systemic NHL. Despite this, an increasing evidence base including limited randomised controlled clinical trial data is informing optimal therapeutic strategies with methotrexate-based induction chemotherapy schedules and intensified consolidation in selected patients. This practice statement represents an evidence-based review of the literature and has been devised to assist healthcare professionals in the diagnosis and management of this disease. This article is protected by copyright. All rights reserved.

A Rare Case of Isolated Intraventricular Primary Central Nervous System Lymphoma in an 85-Year-Old Man

Primary CNS lymphoma (PCNSL) is rare malignant B cell lymphoid tumor of brain which predominantly occurs in supratentorial region in periventricular location. Majority of PCNSL are of DLBCL type and idiopathic in etiology. Here we are reporting a case of primary CNS lymphoma, DLBCL involving extremely uncommon intraventricular location. Central neurocytoma, subependymal giant cell astrocytoma, choroid plexus tumors and meningiomas are the common diagnosis at this site. Aim of reporting this case is to bring awareness of unusual intraventricular location of primary CNS lymphoma which should be kept in mind before considering gross total excision of lesion.

A rare case of Meckel's cave primary lymphoma: a case report and elaboration of the diagnostic algorithm

Management of lesions involving Meckel's cave can represent a challenge for neurosurgeons, because of the deep-seated location and the surrounding complex neurovascular structures. Very small lesions arising from MC are generally asymptomatic and radiological follow-up with head MRI and PET-CT is sufficient to control these lesions. In rare cases, the rapid increase in the size of lesions and the alteration of the neurologic status make early histological characterization mandatory in the plethora of lesions arising from Meckel's cave; a very small percentage is represented by central nervous system lymphomas. Primary diffuse large B-cell lymphoma is the most commonly found. Aggressive surgery, in case of suspicious Meckel's cave lesions, is strongly discouraged, because this procedure may increase the risk of postoperative deficit and provides no survival benefit compared with biopsy alone. The aim of the present paper is to report a very rare case of primary Meckel's cave diffuse large B-cell lymphoma (only seven cases were described in literature) and standardize an operative algorithm to avoid the risks of an incorrect surgical conduct.

Primary central nervous system lymphomas with massive intratumoral hemorrhage: Clinical, radiological, pathological, and molecular features of six cases

Primary central nervous system lymphomas (PCNSLs) rarely exhibit intratumoral hemorrhage. The differential diagnosis of hemorrhagic neoplasms of the central nervous system (CNS) currently includes metastatic carcinomas, melanomas, choriocarcinomas, oligodendrogliomas, and glioblastomas. Here we present the clinical, radiological, pathological, and molecular genetic features of six cases of PCNSL associated with intratumoral hemorrhage. The median age of patients was 75 years, with male predominance. While conventional PCNSLs were associated with low cerebral blood volume (CBV), perfusion magnetic resonance imaging (MRI) revealed elevated CBV in three cases, consistent with vascular proliferation. All six cases were diagnosed pathologically as having diffuse large B-cell lymphoma (DLBCL) with a non-germinal center B-cell-like (non-GCB) phenotype; marked histiocytic infiltrates and abundant non-neoplastic T-cells were observed in most cases. Expression of vascular endothelial growth factor and CD105 in the lymphoma cells and the small vessels, respectively, suggested angiogenesis within the neoplasms. Neoplastic cells were immunohistochemically negative for programmed cell death ligand 1 (PD-L1), while immune cells in the microenvironment were positive for PD-L1. Mutations in the MYD88 gene (MYD88) (L265P) and the CD79B gene (CD79B) were detected in five and one case, respectively. As therapeutic modalities used for PCNSLs differ from those that target conventional hemorrhagic neoplasms, full tissue diagnoses of all hemorrhagic CNS tumors are clearly warranted.

Primary Central Nervous System Lymphoma Mimicking Wernicke's Encephalopathy

Primary central nervous system lymphoma (PCNSL) is a rare disease that can be confused with Wernicke encephalopathy (WE). We have reported here the case of a 31-year-old malnourished man who presented with headache, fever, vomiting, diarrhea, and confusion. His imaging and laboratory findings were indicative of WE. His condition improved after treatment with a high dose of vitamin B1 and intravenous administration of methylprednisolone. However, after continuing to take vitamin B1 for 2 weeks, his symptoms and neuroimaging findings worsened. Increased standardized uptake values of positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (¹⁸F-FDG-PET) and interleukin-10 (IL-10) in the cerebrospinal fluid led to the diagnosis of PCNSL. After treatment with methotrexate and calcium leucovorin, the symptoms and neuroimaging abnormalities disappeared at the 6-month follow-up examination. The possibility of PCNSL should be considered if the routine treatment for WE are ineffective. ¹⁸F-FDG PET and IL-10 may provide a new method for the early diagnosis of PCNSL.

Liquid Biopsy and Other Non-Invasive Diagnostic Measures in PCNSL

Simple Summary

Primary central nervous system lymphoma (PCNSL) is an uncommon disease accounting for around 3% of primary CNS tumors. PCNSL exhibits aggressive clinical behavior and has an overall poor prognosis. The clinical presentation is variable, and there are no specific symptoms. Despite progress in radiographic neuroimaging, stereotactic brain biopsy remains obligatory for definitive diagnosis. Advanced standard diagnostics, including CSF cytology and flow cytometry, have limited sensitivity. Accordingly, there is an urgent need to improve the diagnostic tools for PCNSL, including novel non-invasive procedures. The aim of this review is to present and discuss modern methods that have the potential to contribute standard clinical diagnostics within the next few years.

Abstract

Primary central nervous system lymphoma is a rare but highly aggressive form of non-Hodgkin lymphoma that remains confined to the CNS neuroaxis. The diagnosis of PCNSL requires a high level of suspicion as clinical presentation varies depending on the involved CNS areas. Neurological symptoms and MRI findings may mimic gliomas, demyelinating lesions, or infectious and granulomatous diseases. Almost all PCNSL patients undergo invasive surgical procedures for definite diagnosis. Stereotactic biopsy is still the gold standard in achieving a diagnostic accuracy of 73–97%. Both the potential procedural morbidity and mortality, as well as the time to definite histopathologic diagnosis resulting in delays of treatment initiation, have to be considered. On the contrary, minimally invasive procedures, such as MRI, CSF cytology, and flow cytometry, still have limited value due to inferior specificity and sensitivity. Hence, novel diagnostic approaches, including mutation analyses (MYD88) in circulating tumor DNA (ctDNA) and the determination of microRNAs (miR-21, miR-19b, and miR-92) as well as cytokine levels (IL10 and IL6) in blood, cerebrospinal fluid (CSF), and vitreous fluid (VRF), move into the focus of investigation to facilitate the diagnosis of PCNSL. In this review, we outline the most promising approaches that are currently under clinical consideration.

Differentiation between glioblastoma and primary CNS lymphoma: application of DCE-MRI parameters based on arterial input function obtained from DSC-MRI

OBJECTIVE

This study aimed to evaluate whether arterial input functions (AIFs) obtained from dynamic susceptibility contrast (DSC)-MRI (AIF_DSC) improve the reliability and diagnostic accuracy of dynamic contrast-enhanced (DCE)-derived pharmacokinetic (PK) parameters for differentiating glioblastoma from primary CNS lymphoma (PCNSL) compared with AIFs derived from DCE-MRI (AIF_DCE).

METHODS

This retrospective study included 172 patients with glioblastoma (n = 147) and PCNSL (n = 25). All patients had undergone preoperative DSC- and DCE-MRI. The volume transfer constant (K^trans), volume of the vascular plasma space (v_p), and volume of the extravascular extracellular space (v_e) were acquired using AIF_DSC and AIF_DCE. The relative cerebral blood volume (rCBV) was obtained from DSC-MRI. Intraclass correlation coefficients (ICC) and ROC curves were used to assess the reliability and diagnostic accuracy of individual parameters.

RESULTS

The mean K^trans, v_p, and v_e values revealed better ICCs with AIF_DSC than with AIF_DCE (K^trans, 0.911 vs 0.355; v_p, 0.766 vs 0.503; v_e, 0.758 vs 0.657, respectively). For differentiating all glioblastomas from PCNSL, the mean rCBV (AUC = 0.856) was more accurate than the AIF_DSC-driven mean K^trans, which had the largest AUC (0.711) among the DCE-derived parameters (p = 0.02). However, for glioblastomas with low rCBV (≤ 75th percentile of PCNSL; n = 30), the AIF_DSC-driven mean K^trans and v_p were more accurate than rCBV (AUC: K^trans, 0.807 vs rCBV, 0.515, p = 0.004; v_p, 0.715 vs rCBV, p = 0.045).

CONCLUSION

DCE-derived PK parameters using the AIF_DSC showed improved reliability and diagnostic accuracy for differentiating glioblastoma with low rCBV from PCNSL.

KEY POINTS

• An accurate differential diagnosis of glioblastoma and PCNSL is crucial because of different therapeutic strategies. • In contrast to the rCBV from DSC-MRI, another perfusion imaging technique, the DCE parameters for the differential diagnosis have been limited because of the low reliability of AIFs from DCE-MRI. • When we analyzed DCE-MRI data using AIFs from DSC-MRI (AIF_DSC), AIF_DSC-driven DCE parameters showed improved reliability and better diagnostic accuracy than rCBV for differentiating glioblastoma with low rCBV from PCNSL.

Primary central nervous system lymphoma presenting with Parkinsonism as an initial manifestation: A case report and literature review

Primary central nervous system lymphoma (PCNSL) is a rare intracranial neoplasm in older adults. Tumor-associated parkinsonism (TAP) in PCNSL is extremely rare, and its clinical features are unclear. The present report describes the case of a 75-year-old man who presented with parkinsonism due to multiple hyperintense lesions in the thalamus and periventricular white matter as visualized by magnetic resonance imaging (MRI). Due to the rapid progression of parkinsonism and lesion enlargement, the patient underwent stereotaxic biopsy. Subsequently, his condition was diagnosed as TAP in PCNSL at 2 months after onset. The patient completely recovered after treatment and experienced no recurrence of TAP for 8 months. Although it is difficult to distinguish TAP from vascular parkinsonism (VP) at initial consultation, the early diagnosis of PCNSL is important for improving prognosis. In the case of rapidly progressing parkinsonism, one should suspect the possibility of TAP associated with early-stage PCNSL. Early treatment improves the chances of remission and decreases the possibility of recurrence.

Inflammatory Brain Lesions as Omen of Primary Central Nervous System Lymphoma: A Case Report and Literature Review

We report a rare case that was initially diagnosed as an inflammatory lesion and ultimately confirmed as primary central nervous system lymphoma (PCNSL) in an immunocompetent patient who was not treated with corticosteroid prior to the initial biopsy. A 70-year-old female patient presented with numbness in the left side of face, arm, and leg. Brain magnetic resonance imaging (MRI) revealed a lesion with intense gadolinium (Gd)-enhancement in the ventral portion of the midbrain. A stereotactic biopsy demonstrated mixed T-cell and B-cell infiltrating inflammatory lesions without demyelination. Three months after postoperative treatment with steroid, the lesion markedly decreased on follow-up MRI. Twenty-six months after the initial attack, she complained of dysarthria and urinary incontinence. Repetitive MRI showed a lesion with homogeneous enhancement, extensively involving the bilateral cerebral hemisphere, corpus callosum, and the right middle cerebellar peduncle. The confirmed diagnosis was diffuse large B-cell lymphoma on the second biopsy. Despite our best efforts, she died 38 months after disease onset. Based on review of the literature and our case, preceding inflammatory lesions are not always demyelinating and T-cell dominant inflammatory lesions. When the initial biopsy reveals an inflammatory lesion in an old-aged patient, the clinician should keep in mind the development of PCNSL and perform close clinical and radiological observations for a timely diagnosis.

A single-centre study of frame-based stereotactic brain biopsies

OBJECTIVE

We aimed to evaluate the concordance between the image-based and the tissue-based diagnosis using frame-based stereotactic biopsy.

MATERIALS AND METHODS

Medical records of biopsy procedures from 2000 to 2017 were reviewed. The radiologists' preoperative reports, biopsy procedures and postoperative histopathological diagnoses were retrieved. We compared the preoperative image-based diagnosis with the final histopathological diagnosis.

RESULTS

We identified 125 biopsy procedures performed in 123 patients. The concordance between image-based and histopathological diagnoses varied between 53.3% and 87.5%. The concordance of diagnosis concerning both tumor entity (i.e. cell type) and WHO grade was 54.6%. The diagnostic yield was 95.2%. There was overall morbidity of 10.4%, and a mortality rate of 0.8%. Minor complications occurred in 4.0% of the cases, while clinically significant complications occurred in 6.4% of the cases.

CONCLUSIONS

There was suboptimal concordance between radiological and histopathological diagnosis. Also, there was a tendency of histopathological undergrading. We confirm that frame-based stereotactic biopsies have a high diagnostic yield and a low rate of clinically significant complications and mortality.

Integration of the B-Cell Receptor Antigen Neurabin-I/SAMD14 Into an Antibody Format as New Therapeutic Approach for the Treatment of Primary CNS Lymphoma

Recently, neurabin-I and SAMD14 have been described as the autoantigenic target of approximately 66% of B-cell receptors (BCRs) of primary central nervous system lymphomas (PCNSL). Neurabin-I and SAMD14 share a highly homologous SAM domain that becomes immunogenic after atypical hyper-N-glycosylation (SAMD14 at ASN339 and neurabin-I at ASN1277). This post-translational modification of neurabin-I and SAMD14 seems to lead to a chronic immune reaction with B-cell receptor activation contributing to lymphoma genesis of PCNSLs. The selective tropism of PCNSL to the CNS corresponds well to the neurabin-I and SAMD14 protein expression pattern. When conjugated to Pseudomonas Exotoxin A (ETA´), the PCNSL reactive epitope exerts cytotoxic effects on lymphoma cells expressing a SAMD14/neurabin-I reactive BCR. Thus, the reactive epitopes of SAMD14/neurabin-I might be useful to establish additional therapeutic strategies against PCNSL. To test this possibility, we integrated the PCNSL-reactive epitope of SAMD14/neurabin-I into a heavy-chain-only Fab antibody format in substitution of the variable region. Specific binding of the prokaryotically produced SAMD14/neurabin-I Fab-antibody to lymphoma cells and their internalization were determined by flow cytometry. Since no established EBV-negative PCNSL cell line exists, we used the ABC-DLBCL cell lines OCI-Ly3 and U2932, which were transfected to express a SAMD14/neurabin-I reactive BCR. The SAMD14/neurabin-I Fab antibody bound specifically to DLBCL cells expressing a BCR with reactivity to SAMD14/neurabin-I and not to unmanipulated DLBCL cell lines. Eukaryotically produced full-length IgG antibodies are well established as immunotherapy format. Therefore, the PCNSL-reactive epitope of SAMD14/neurabin-I was cloned into a full-length IgG1 format replacing the variable domains of the light and heavy chains. The IgG1-format SAMD14/neurabin-I construct was found to specifically bind to target lymphoma cells expressing a SAMD14/neurabin-I reactive B cell receptor. In addition, it induced dose-dependent relative cytotoxicity against these lymphoma cells when incubated with PBMCs. Control DLBCL cells are not affected at any tested concentration. When integrated into the Fab-format and IgG1-format, the PCNSL-reactive epitope of SAMD14/neurabin-I functions as B-cell receptor Antigen for Reverse targeting (BAR). In particular, the IgG1-format BAR-body approach represents a very attractive therapeutic format for the treatment of PCNSLs, considering its specificity against SAMD14/neurabin-I reactive BCRs and the well-known pharmacodynamic properties of IgG antibodies.

Histopathological variation in the demyelinating sentinel lesion of primary central nervous system lymphoma

Background:

Primary central nervous system lymphoma (PCNSL) is one of the least common malignant brain tumors. It is usually diagnosed initially as diffuse large B cell lymphoma (DLBCL). In rare cases, however, a demyelinating lesion referred to as a “sentinel lesion” precedes the actual diagnosis, which usually depicts two distinct patterns of inflammatory cells during histological analysis. This case report describes a unique histological finding and describes the recognized variations in sentinel lesion histopathology.

Case Description:

A 78-year-old female patient was found to have multiple white matter lesions of various degrees of enhancement on post-contrast T1-weighted magnetic resonance imaging. A stereotactic biopsy of a heterogeneous lesion in the left occipital lobe was performed, which revealed demyelination along with lymphocytic infiltration, reactive astrocytosis, abundant T cells, and foamy macrophages. There was no evidence of monoclonality, rapid regression of all lesions occurred, and the patient was thus treated for tumefactive demyelination. Three months later, all of the residual lesions had enlarged and were homogeneously enhancing. An endoscopic-guided biopsy of the right periventricular lesion showed diffuse atypical lymphoid cells.

Conclusion:

The sentinel lesion of PCNSL expresses a variable histological pattern of inflammatory cells. This case demonstrates a unique and rare picture of mixed perivascular and parenchymal infiltration of inflammatory cells, highlighting the importance of repeated biopsies and/or radiological examinations to obtain an accurate diagnosis.

Comparison of Radiomics-Based Machine-Learning Classifiers in Diagnosis of Glioblastoma From Primary Central Nervous System Lymphoma

Purpose: The purpose of the current study was to evaluate the ability of magnetic resonance (MR) radiomics-based machine-learning algorithms in differentiating glioblastoma (GBM) from primary central nervous system lymphoma (PCNSL).

Method: One-hundred and thirty-eight patients were enrolled in this study. Radiomics features were extracted from contrast-enhanced MR images, and the machine-learning models were established using five selection methods (distance correlation, random forest, least absolute shrinkage and selection operator (LASSO), eXtreme gradient boosting (Xgboost), and Gradient Boosting Decision Tree) and three radiomics-based machine-learning classifiers [linear discriminant analysis (LDA), support vector machine (SVM), and logistic regression (LR)]. Sensitivity, specificity, accuracy, and areas under curves (AUC) of models were calculated, with which the performances of classifiers were evaluated and compared with each other.

Result: Brilliant discriminative performance would be observed among all classifiers when combined with the suitable selection method. For LDA-based models, the optimal one was Distance Correlation + LDA with AUC of 0.978. For SVM-based models, Distance Correlation + SVM was the one with highest AUC of 0.959, while for LR-based models, the highest AUC was 0.966 established with LASSO + LR.

Conclusion: Radiomics-based machine-learning algorithms potentially have promising performances in differentiating GBM from PCNSL.

Primary large B-cell lymphoma of the central nervous system with cyclin D1 expression and t(11;14) (IGH-CCND1): Diffuse large B-cell lymphoma with CCND1 rearrangement or mantle cell lymphoma?

Mantle cell lymphomas (MCLs) are the prototypic B-cell non-Hodgkin lymphomas defined by cyclin D1 gene (CCND1; or other cyclin D family gene) rearrangements. However, extremely rare cases of diffuse large B-cell lymphomas (DLBCLs) harboring CCND1 rearrangements, resulting in cyclin D1 protein expression, have also been reported. In this report, we describe an unusual primary large B-cell lymphoma of non-germinal center immunophenotype of the central nervous system (CNS) in an elderly male patient, which was negative for CD5 and SOX11, and exhibited cyclin D1 expression. Fluorescence in situ hybridization analysis detected IGH-CCND1 and BCL6 rearrangements. This case may represent the first report of a primary CNS DLBCL with IGH-CCND1 rearrangement. The clinico-pathologic features that can help differentiate primary CNS MCL from primary DLBCL of the CNS with IGH-CCND1 rearrangement are discussed.

Molecular Diagnostics in Lymphoid Neoplasms of the Central Nervous System

Primary lymphoid neoplasms of the central nervous system are rare tumors that span a wide range of histopathologic appearances and can overlap occasionally with non-neoplastic processes. Application of modern molecular techniques has not only begun to unravel their unique underlying biology but has also started to lay a valuable diagnostic and therapeutic framework for these frequently aggressive malignancies. This review summarizes the existing landscape of clinicopathologic and genomic features of lymphoid neoplasms that may arise primarily within the central nervous system.

Intraventricular pseudolymphoma a case review

Intracranial pseudolymphoma is a rare entity. We report the case of a 44 year old female who presented with headaches and was noted to have a right lateral ventricular lesion on a background history of Burkitt's lymphoma. She underwent biopsy of said lesion and was found to have benign reactive lymphoid tissue. This is the third reported case in literature of intracranial pseudolymphoma and the first reported intraventricular lesion.

Clinical Characteristics, Surgical Outcomes, and Prognostic Factors of Intracranial Primary Central Nervous System Lymphoma

BACKGROUND

Intracranial primary central nervous system lymphoma (PCNSL) is a rare aggressive malignant tumor with poor prognosis. The effect of surgical resection on intracranial PCNSL is still controversial. This study investigates the efficacy and safety of surgical resection, as well as to analyze the clinical characteristics and prognostic factors of intracranial PCNSL.

METHODS

The clinical materials of 89 consecutive patients with intracranial PCNSL were analyzed retrospectively. Outcome in survival was assessed by progression-free survival (PFS) and overall survival (OS). Univariate and multivariate analyses were performed for various potential prognostic factors to identify independent prognostic factors of intracranial PCNSL.

RESULTS

Among the 89 patients, gross total resection (GTR) was achieved in 57 patients (64.0%), subtotal resection (STR) in 14 patients (15.8%), and biopsy in 18 patients (20.2%).The PFS and OS at 2 years were estimated at 32.3% and 74.1%, respectively. The median PFS was 20 months (95% confidence interval, 16-23) and the median OS was 32 months (95% confidence interval, 25-38). Patients with surgical resection (GTR and STR) had better PFS than those with biopsy, and the difference of PFS was statistically significant (P = 0.007). However, the difference of OS was not statistically significant (P = 0.062). Multivariate analysis showed that invasion of deep structure was the only independent risk factor for intracranial PCNSL. Eleven patients (12.4%) had surgical complications, mainly including limb weakness and visual field defect.

CONCLUSIONS

For intracranial PCNSL, surgical excision can improve PFS but not OS. Invasion of deep structure was the only independent risk factor for intracranial PCNSL.

Nonneuroendocrine Neoplasms of the Pituitary Region

CONTEXT

Although most sellar lesions are related to pituitary adenomas, the region gives rise to a variety of neoplasms that can be associated with substantial morbidity and/or mortality.

DESIGN

Information from reviews and guidelines of relevant societies dealing with such neoplasms, as well as articles that have provided new developments that made important contributions to their pathogenesis and treatment up to 2018, were obtained: public indexes such as PubMed/MEDLINE were used with the relevant search items.

RESULTS

Sellar neoplasms have a worse outcome than pituitary adenomas that is related not only to their natural history but also to side effects of therapies and evolving endocrine and/or hypothalamic deficiencies. Recent imaging advances have established the radiological fingerprint of some of these neoplasms, and several chromosomal aberrations have also been identified. Although established approaches along with new surgical and radiotherapeutic approaches remain the main treatment modalities, recent evidence has provided insight into their molecular pathogenesis involving, other than chemotherapy, treatments with targeted agents as in gliomas and craniopharyngiomas bearing BRAF mutations. Development of predictive markers of recurrences may also identify high-risk patients, including proliferative markers and expression of the progesterone receptor in meningiomas, and lead to less aggressive surgery. Owing to the rarity and complexity of these neoplasms, patients should be managed in dedicated centers.

CONCLUSIONS

The diagnosis and management of sellar neoplasms necessitate a multidisciplinary approach. Following evolving recent advances in their diagnosis and therapy, such a multidisciplinary approach needs to be extended to establish evidence-based diagnostic and management plans.

Rare cases of primary central nervous system anaplastic variant of diffuse large B-cell lymphoma

BACKGROUND

Primary central nervous system (CNS) diffuse large B-cell lymphoma (DLBCL) is a rare intracranial tumor, defined as DLBCL arising from the brain, spinal cord, leptomeninges and eye, with an overall annual incidence of 5 cases per million. The primary CNS anaplastic variant of DLBCL (A-DLBCL) is even less common; to our knowledge, there are only two other case reports in the literature. The aim of this report is to present rare cases of primary CNS A-DLBCL and study their clinicopathologic and genetic features.

CASE PRESENTATION

We report 3 patients, two men and one woman, aged 54, 55 and 67 years old, with primary CNS A-DLBCL. All 3 patients had a high International Extranodal Lymphoma Study Group (IELSG) score; although the patients were treated with methotrexate-based regimens and/or with radiation therapy, the overall survival was only 2, 5, and 8 months. All 3 patients presented with characteristic features of perivascular space infiltration with bizarre-shaped tumor cells, leading to the diagnosis of primary CNS A-DLBCL. Concurrent of MYC and BCL2 and/or BCL6 abnormalities and MYC/BCL2 double-expressor DLBCL occurred in all 3 patients; two patients had MYC/BCL2/BCL6 triple extra copies, and one patient had MYC extra copy and BCL6 translocation. All 3 patients displayed mutations in MYD88 L265P and nuclear positivity for RELA, RELB and/or c-Rel, indicating constitutive activation of the NF-κB pathway.

CONCLUSIONS

These cases shed light on the unique genetic alterations and biological features of primary CNS A-DLBCL. Patients with primary CNS A-DLBCL may often have a MYC/BCL2 double-expressor and concurrent MYC and BCL2 and/or BCL6 genetic abnormalities, as well as constitutive activation of the NF-κB pathway. Primary CNS A-DLBCL follows a very aggressive disease course and poor prognosis. In the future, a large number of cases should be analyzed, and the evaluation of molecular genetic characteristics could help with practical and therapeutic implications for primary CNS A-DLBCL.

Diagnostic performance of DWI for differentiating primary central nervous system lymphoma from glioblastoma: a systematic review and meta-analysis

OBJECTIVE

The purpose of this meta-analysis was to evaluate the diagnostic performance of diffusion-weighted imaging (DWI) for differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma (GBM).

MATERIALS AND METHODS

A thorough search of the databases including PubMed, EMBASE, and Cochrane Library was carried out and the data acquired were up to November 1, 2017. The quality of the studies involved was evaluated using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies, revised version). Multiple analytic values including sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the summary receiver operating characteristic (SROC) curve were calculated and pooled for the statistical analysis. The subgroup analysis was also performed to explore the heterogeneity.

RESULTS

Eight retrospective studies (461 patients with 461 lesions) were included. The pooled SEN, SPE, PLR, NLR, and DOR with 95% confidence interval (CI) were 0.82 [95% CI 0.70-0.90], 0.84 [95% CI 0.75-0.90], 4.96 [95% CI 3.20-7.69], 0.22 [95% CI 0.13-0.37], and 22.85 [95% CI 10.42-50.11], respectively. The area under the curve (AUC) given by SROC curve was 0.90 [95% CI 0.87-0.92]. The subgroup analysis indicated the slice thickness of the images (> 3 mm versus ≤ 3 mm) was a significant factor affecting the heterogeneity. No existence of significant publication bias was confirmed with Deeks' test.

CONCLUSIONS

DWI showed moderate diagnostic performance for differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma (GBM). Moreover, it is of clinical significance using DWI combined with conventional MRI to differentiate PCNSL from GBM.

MRI as a diagnostic biomarker for differentiating primary central nervous system lymphoma from glioblastoma: A systematic review and meta-analysis

BACKGROUND

Accurate preoperative differentiation of primary central nervous system lymphoma (PCNSL) and glioblastoma is clinically crucial because the treatment strategies differ substantially.

PURPOSE

To evaluate the diagnostic performance of MRI for differentiating PCNSL from glioblastoma.

STUDY TYPE

Systematic review and meta-analysis.

SUBJECTS

Ovid-MEDLINE and EMBASE databases were searched to find relevant original articles up to November 25, 2018. The search term combined synonyms for "lymphoma," "glioblastoma," and "MRI."

FIELD STRENGTH/SEQUENCE

Patients underwent at least one MRI sequence including diffusion-weighted imaging (DWI), dynamic susceptibility-weighted contrast-enhanced imaging (DSC), dynamic contrast-enhanced imaging (DCE), arterial spin labeling (ASL), susceptibility-weighted imaging (SWI), intravoxel incoherent motion (IVIM), and magnetic resonance spectroscopy (MRS) using 1.5 or 3 T.

ASSESSMENT

Quality assessment was performed according to the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

STATISTICAL TESTS

Hierarchical logistic regression modeling was used to obtain pooled sensitivity and specificity. Meta-regression was performed.

RESULTS

Twenty-two studies with 1182 patients were included. MRI sequences demonstrated high overall diagnostic performance with pooled sensitivity of 91% (95% confidence interval [CI], 87-93%) and specificity of 89% (95% CI, 85-93%). The area under the hierarchical summary receiver operating characteristic curve was 0.92 (95% CI, 0.90-0.94). Studies using DSC or ASL showed high diagnostic performance (sensitivity of 93% [95% CI, 89-97%] and specificity of 91% [95% CI, 86-96%]). Heterogeneity was only detected in specificity (I² = 66.84%) and magnetic field strength was revealed to be a significant factor affecting study heterogeneity.

DATA CONCLUSION

MRI showed overall high diagnostic performance for differentiating PCNSL from glioblastoma, with studies using DSC or ASL showing high diagnostic performance. Therefore, MRI sequences including DSC or ASL is a potential diagnostic tool for differentiating PCNSL from glioblastoma.

LEVEL OF EVIDENCE

3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;50:560-572.

Psychosis as an indicator of recurrent non-Hodgkin's lymphoma: a rare presentation

Psychotic manifestations of brain tumours are rare but described in the literature mostly along with other neurological deficits. Memory loss, difficulty in attention and concentration, depression, anxiety, and mood symptoms are commonly described in brain tumours. A schizophrenia-like picture without a deficit in motor or sensory function may land the clinician into a diagnostic dilemma. Primary central nervous system lymphoma (PCNSL) is a highly malignant disease with high mortality and needs immediate attention. Our case which had a unique recurrence in the postoperative period with psychotic symptoms can be an eye-opener to be more vigilant about underlying clinical extension.

Utility of arterial spin labelling MRI for discriminating atypical high-grade glioma from primary central nervous system lymphoma

AIM

To evaluate the ability of arterial spin labelling (ASL) magnetic resonance imaging (MRI) in differentiating primary central nervous system lymphoma (PCNSL) from atypical high-grade glioma (HGG), as well as exploring the underlying pathological mechanisms.

METHODS AND MATERIALS

Twenty-three patients with PCNSL and 17 patients with atypical HGG who underwent ASL-MRI were identified retrospectively. Absolute cerebral blood flow (aCBF) and normalised cerebral blood flow (nCBF) values were obtained, and were compared between PCNSL and atypical HGG using the Mann-Whitney U-test. The performance in discriminating between PCNSL and atypical HGG was evaluated using receiver-operating characteristics analysis and area-under-the-curve (AUC) values for aCBF and nCBF. The correlation between microvessel density (MVD) and aCBF was determined by Spearman's correlation analysis.

RESULTS

Atypical HGG demonstrated significantly higher aCBF, nCBF, and MVD values than PCNSL (p<0.05). The diagnostic accuracy of discriminating PCNSL from atypical HGG showed AUC=0.877 (95% confidence interval [CI] 0.735-0.959) for aCBF, and AUC=0.836 (95% confidence interval [CI] 0.685-0.934) for nCBF. There was a moderate positive correlation between aCBF values of region of interest (ROI >30 mm²) in the enhanced area and MVD values (rho=0.579, p=0.0001), and a strong positive correlation between aCBF values MVD based on "point-to-point biopsy" (rho=0.83, p=0.0029). Interobserver agreements for aCBF and nCBF were excellent (ICC >0.75).

CONCLUSIONS

ASL perfusion MRI is a useful imaging technique for the discrimination between atypical HGG and PCNSL, which may be determined by the difference of MVD between them.

Molecular analysis in liquid biopsies for diagnostics of primary central nervous system lymphoma: Review of literature and future opportunities

Primary central nervous system lymphoma (PCNSL) is an aggressive lymphoma with a poor prognosis, for which accurate and timely diagnosis is of utmost importance. Unfortunately, diagnosis of PCNSL can be challenging and a brain biopsy (gold standard for diagnosis) is an invasive procedure with the risk of major complications. Thus, there is an urgent need for an alternative strategy to diagnose and monitor these lymphomas. Currently, liquid biopsies from cerebrospinal fluid (CSF) are used for cytomorphologic and flow cytometric analysis. Recently, new biomarkers such as genetic mutations and interleukins have been identified in these liquid biopsies, further expanding the diagnostic armamentarium. In this review we present an overview of genetic aberrations (>70) reported in this unique lymphoma. Of these genes, we have selected those that are reported in ≥3 studies. Half of the selected genes are implicated in the NFκB pathway (CARD11, CD79B, MYD88, TBL1XR1 and TNFAIP3), while the other half are not related to this pathway (CDKN2A, ETV6, PIM1, PRDM1 and TOX). Although this underlines the crucial role of the NFκB pathway in PCNSL, CD79B and MYD88 are at present the only genes mentioned in liquid biopsy analysis. Finally, a stepwise approach is proposed for minimally invasive liquid biopsy analysis and work-up of PCNSL, incorporating molecular analysis. Prioritization and refinements of this approach can be constructed based upon multidisciplinary collaboration as well as novel scientific insights.

Primary central nervous system lymphoma and atypical glioblastoma: Differentiation using radiomics approach

OBJECTIVES

To evaluate the diagnostic performance of magnetic resonance (MR) radiomics-based machine-learning algorithms in differentiating primary central nervous system lymphoma (PCNSL) from non-necrotic atypical glioblastoma (GBM).

METHODS

Seventy-seven patients (54 individuals with PCNSL and 23 with non-necrotic atypical GBM), diagnosed from January 2009 to April 2017, were enrolled in this retrospective study. A total of 6,366 radiomics features, including shape, volume, first-order, texture, and wavelet-transformed features, were extracted from multi-parametric (post-contrast T1- and T2-weighted, and fluid attenuation inversion recovery images) and multiregional (enhanced and non-enhanced) tumour volumes. These features were subjected to recursive feature elimination and random forest (RF) analysis with nested cross-validation. The diagnostic abilities of a radiomics machine-learning classifier, apparent diffusion coefficient (ADC), and three readers, who independently classified the tumours based on conventional MR sequences, were evaluated using receiver operating characteristic (ROC) analysis. Areas under the ROC curves (AUC) of the radiomics classifier, ADC value, and the radiologists were compared.

RESULTS

The mean AUC of the radiomics classifier was 0.921 (95 % CI 0.825-0.990). The AUCs of the three readers and ADC were 0.707 (95 % CI 0.622-0.793), 0.759 (95 %CI 0.656-0.861), 0.695 (95 % CI 0.590-0.800) and 0.684 (95 % CI0.560-0.809), respectively. The AUC of the radiomics-based classifier was significantly higher than those of the three readers and ADC (p< 0.001 for all).

CONCLUSIONS

Large-scale radiomics with a machine-learning algorithm can be useful for differentiating PCNSL from atypical GBM, and yields a better diagnostic performance than human radiologists and ADC values.

KEY POINTS

• Machine-learning algorithm radiomics can help to differentiate primary central PCNSL from GBM. • This approach yields a higher diagnostic accuracy than visual analysis by radiologists. • Radiomics can strengthen radiologists' diagnostic decisions whenever conventional MRI sequences are available.

Case of Primary Leptomeningeal Lymphoma Presenting with Papilloedema and Characteristics of Pseudotumor Syndrome

The authors describe an immunocompetent, 50-year-old man who complained of a daily transient blurring of his vision with bilateral papilloedema. His visual acuity was 20/20 OU, and the blind spot was enlarged bilaterally. There was intracranial hypertension, but imaging for systemic and brain tumours were negative. These findings suggested a diagnosis of the pseudotumor syndrome. However, MRI showed leptomeningeal enhancement, and acetazolamide successfully resolved his visual symptoms and papilloedema. Cytology and flow cytometry of the CSF led to the final diagnosis of primary leptomeningeal lymphoma (PLML). Clinicians need to be aware that a case of PLML may be misdiagnosed as peudotumor cerebri.