A systematic approach to the diagnosis of suspected central nervous system lymphoma

Cardiac sarcoidosis and neurosarcoidosis - multidisciplinary approach for diagnosis

PURPOSE OF REVIEW

The current review aims to highlight the role of multidisciplinary approach in the diagnosis of patients with cardiac and neurosarcoidosis. Multidisciplinary approach integrates the available clinical information, imaging and histopathological results aiming to reach a definite or at least provisional diagnosis and allow appropriate management. Multidisciplinary approach is the reference standard for diagnosis of interstitial lung disease and should be strongly considered in complex clinical conditions such as cardiac sarcoidosis (CS) and neurosarcoidosis.

RECENT FINDINGS

Histopathological confirmation of noncaseating granulomatous inflammation provides a definite diagnosis of sarcoidosis involving any organ. However, a provisional high confidence or even definite clinical diagnosis can be reached using multidisciplinary evaluation of all available evidence. The diagnosis of cardiac sarcoidosis and neurosarcoidosis requires the integration of different expertise based on the current diagnostic criteria sets. Identifying typical or at least compatible patterns on advanced imaging modalities (CMR and Fluro-Deoxy-Glucose Positron Emission Tomography (FDG-PET)) seems key for the diagnosis of CS, while a confident diagnosis of extra-cardiac disease supports an at least provisional diagnosis. Similarly, in neurosarcoidosis integrating compatible MRI appearances and cerebrospinal fluid results in patients with systemic sarcoidosis allows an at least provisional diagnosis. Exclusion of alternative differential diagnoses is crucial and requires high clinical suspicion, imaging review expertise and appropriate tests performance.

SUMMARY

There have been considerable advances in the diagnostic approach of patients with cardiac and neurosarcoidosis. Multidisciplinary approach for both diagnosis and management is required to reach a confident clinical diagnosis and should be applied when possible.

Comparison of the diagnostic significance of cerebrospinal fluid metagenomic next-generation sequencing copy number variation analysis and cytology in leptomeningeal malignancy

BACKGROUND

Diagnosis and monitoring of leptomeningeal malignancy remain challenging, and are usually based on neurological, radiological, cerebrospinal fluid (CSF) and pathological findings. This study aimed to investigate the diagnostic performance of CSF metagenomic next-generation sequencing (mNGS) and chromosome copy number variations (CNVs) analysis in the detection of leptomeningeal malignancy.

METHODS

Of the 51 patients included in the study, 34 patients were diagnosed with leptomeningeal malignancies, and 17 patients were diagnosed with central nervous system (CNS) inflammatory diseases. The Sayk's spontaneous cell sedimentation technique was employed for CSF cytology. And a well-designed approach utilizing the CSF mNGS-CNVs technique was explored for early diagnosis of leptomeningeal malignancy.

RESULTS

In the tumor group, 28 patients were positive for CSF cytology, and 24 patients were positive for CSF mNGS-CNVs. Sensitivity and specificity of CSF cytology were 82.35% (95% CI: 66.83-92.61%) and 94.12% (95% CI: 69.24-99.69%). In comparison, sensitivity and specificity of CSF mNGS-CNV were 70.59% (95% CI: 52.33-84.29%) and 100% (95% CI: 77.08-100%). There was no significant difference in diagnostic consistency between CSF cytology and mNGS-CNVs (p = 0.18, kappa = 0.650).

CONCLUSIONS

CSF mNGS-CNVs tend to have higher specificity compared with traditional cytology and can be used as a complementary diagnostic method for patients with leptomeningeal malignancies.

Diagnostics and treatment delay in primary central nervous system lymphoma: What the neurosurgeon should know

PURPOSE

The gold standard for diagnostics in primary central nervous system lymphoma (PCNSL) is histopathological diagnosis after stereotactic biopsy. Yet, PCNSL has a multidisciplinary diagnostic work up, which associated with diagnostic delay and could result in treatment delay. This article offers recommendations to neurosurgeons involved in clinical decision-making regarding (novel) diagnostics and care for patients with PCNSL with the aim to improve uniformity and timeliness of the diagnostic process for patients with PCNSL.

METHODS

We present a mini review to discuss the role of stereotactic biopsy in the context of novel developments in diagnostics for PCNSL, as well as the role for cytoreductive surgery.

RESULTS

Cerebrospinal fluid-based diagnostics are supplementary and cannot replace stereotactic biopsy-based diagnostics.

CONCLUSION

Histopathological diagnosis after stereotactic biopsy of the brain remains the gold standard for diagnosis. Additional diagnostics should not be a cause of diagnostic delay. There is currently no sufficient evidence supporting cytoreductive surgery in PCNSL, with recent studies showing contradictive data and suboptimal study designs.

Intrathecal IgM synthesis as a diagnostic marker in patients with suspected CNS lymphoma

For CNS lymphomas (CNSL), there is a high need for minimally invasive and easily obtainable diagnostic markers. Intrathecal IgM synthesis can easily be determined in routine CSF diagnostics. The aim of this study was to systematically investigate the diagnostic potential of intrathecal IgM synthesis in primary and secondary CNSL (PCNSL and SCNSL). In this retrospective study, patients with a biopsy-proven diagnosis of PCNSL or SCNSL were compared with patients with other neurological diseases in whom CNSL was initially the primary radiological differential diagnosis based on MRI. Sensitivity and specificity of intrathecal IgM synthesis were calculated using receiver operating characteristic curves. Seventy patients with CNSL were included (49 PCNSL and 21 SCNSL) and compared to 70 control patients. The sensitivity and specificity for the diagnosis of CNSL were 49% and 87%, respectively, for the entire patient population and 66% and 91% after selection for cases with tumor access to the CSF system and isolated intrathecal IgM synthesis. In cases with MRI-based radiological suspicion of CNSL, intrathecal IgM synthesis has good specificity but limited sensitivity. Because of its low-threshold availability, analysis of intrathecal IgM synthesis has the potential to lead to higher diagnostic accuracy, especially in resource-limited settings, and deserves further study.

Not everything is ischemic optic neuropathy

A 71-year-old woman developed sudden, painful, decreased vision in the left eye accompanied by progressive instability. Initial examination revealed left optic disc edema, and macular optical coherence tomography confirmed the presence of intraretinal and subretinal fluid, as well as hyperreflective material under the retinal pigment epithelium. Subsequent investigations, including brain magnetic resonance imaging and a comprehensive serological analysis, ruled out infectious and autoimmune causes, further complicating the diagnostic picture. The patient's vision in both eyes continued to deteriorate, prompting empirical corticosteroid treatment. While the vision improved, the case took an unexpected turn with worsening neurological symptoms. Ultimately a brain biopsy was consistent with diffuse large B-cell lymphoma.

Intraoperative pathologic diagnosis of central nervous system lymphomas: A comparison of frozen and permanent section diagnoses, and the significance of preoperative imaging

BACKGROUND

Central nervous system (CNS) lymphomas, either primary or secondary in origin, are rare malignant tumors affecting the brain, spinal cord, or leptomeninges. Diagnosis of CNS lymphomas is complicated by their diverse clinical presentations, radiological features, and histopathological characteristics. Although frozen section (FS) analysis is commonly employed for various CNS tumors, its role and accuracy in CNS lymphoma diagnosis are less explored. In this study, we conducted a comparative analysis to assess the impact of knowledge of preoperative imaging on enhancing the accuracy of FS diagnosis in CNS lymphomas.

METHODS

Data collection involved a retrospective review of CNS lymphoma patients from January 2009 to August 2021. Patients who underwent intraoperative consultation were included, excluding those with prior cortisone treatment. The dataset incorporated patient demographics, classification as primary or secondary lymphoma, radiological preliminary diagnoses, FS diagnosis, and permanent section diagnosis. We employed various archived materials, including FSs, touch imprint slides, crush cytology slides, H&E-stained sections, and immunohistochemical stains, and re-evaluated all slides for diagnostic validation.

RESULTS

Our study included 25 patients, of whom 60 % were female and had a mean age of 56.5 years. Preoperative radiology data were available for 80 % of cases, with preliminary diagnoses commonly including lymphoma and/or metastasis. Intraoperative consultation results indicated lymphoma in 18 (72 %) patients, with discordance observed in 28 % of cases when compared to permanent section diagnoses. Most permanent section diagnoses were diffuse large B-cell lymphomas (92 %), with the remainder being T-cell non-Hodgkin lymphoma (4 %) and follicular lymphoma (4 %). Intraoperative misdiagnoses were significantly associated with the absence of knowledge of preoperative imaging.

CONCLUSION

Our study demonstrates the reliability of FS diagnosis for CNS lymphomas during surgery, with a favorable complete concordance rate of 72 % when compared to permanent diagnoses. Importantly, lack of knowledge of preoperative imaging significantly impaired diagnostic accuracy in FS, emphasizing the need for close collaboration between pathologists and radiologists.

Essentials for early diagnosis of primary intramedullary spinal cord lymphoma. How to suspect primary intramedullary spinal cord lymphoma early and proceed to invasive biopsy? A case report and literature review

Background

Primary intramedullary spinal cord lymphoma (PISCL) is an extremely rare condition. Early diagnosis is very difficult due to the nonspecific clinical and imaging findings. A biopsy is essential for a definitive diagnosis, but courage is required to perform the surgery. Here, we present a case of PISCL and suggest useful indicators for accurate diagnosis of this pathological entity.

Case Description

A 70-year-old woman presented with subacute bilateral lower-limb paralysis, disturbance of warm and pain sensations, and vesicorectal disturbance. Magnetic resonance imaging showed a contrast-enhanced mass from C7 to Th2 and large, edematous lesions from the upper cervical to lower thoracic spinal cord. Elevated uptake of 18F-fluoro-2-deoxy-D-glucose (FDG) was identified in the enhanced regions on FDG-positron emission tomography (PET). Cerebrospinal fluid (CSF) analysis revealed highly elevated levels of β2-microglobulin (β2-MG). Steroid pulse therapy and therapeutic plasma exchange were performed for suspected myelitis, but symptoms did not improve. Spinal cord biopsy was, therefore, performed for treatment-resistant myelopathy. Histopathological examination revealed diffuse large B-cell lymphoma, which was diagnosed as PISCL because systemic examination showed no other findings suggestive of malignant lymphoma.

Conclusion

In cases with poor response to treatment and a progressive course, PISCL should be considered, and spinal cord biopsy should be performed if PET shows increased 18F-FDG uptake and β2-MG is elevated in CSF.

Central Nervous System Lymphoma

Central nervous system lymphoma (CNSL) is a rare and aggressive malignancy that primarily affects the brain, spinal cord, and meninges. This article provides a comprehensive overview of the current understanding of CNSL encompassing its epidemiology, pathophysiology, clinical presentation, diagnosis, treatment modalities, and prognosis. Although the main focus is on primary CNS lymphoma (PCNSL), ocular lymphoma, primary leptomeningeal lymphoma, and secondary CNS lymphoma are also discussed. The pathobiology of CNSL involves the infiltration of malignant lymphocytes within the CNS parenchyma or leptomeninges. Various risk factors and immunological mechanisms contribute to its development, including immunodeficiency states, chronic inflammation, and genomic alterations. Accurate diagnosis is crucial for appropriate management, given the heterogeneous clinical presentation. The neuroimaging, systemic imaging, and other modalities for diagnosis and evaluation for extent of disease involvement will be discussed. Additionally, the importance of histopathological examination, cerebrospinal fluid (CSF) analysis, and molecular testing in confirming the diagnosis and guiding treatment decisions are highlighted. The treatment landscape for CNSL has evolved significantly. Therapeutic approaches encompass a multimodal strategy combining high-dose methotrexate-based chemotherapy, consolidation with whole-brain radiation therapy, and high-dose chemotherapy with stem cell rescue. Recent advancements in targeted therapies and immunomodulatory agents offer promising avenues for future treatment options. We review the clinical outcomes and prognostic factors influencing the survival of CNSL patients, including age, performance status, disease stage, and genetic abnormalities.

How I treat secondary CNS involvement by aggressive lymphomas

Secondary central nervous system (CNS) lymphoma (SCNSL) is a rare but clinically challenging scenario with historically disappointing outcomes. SCNSL refers to lymphoma that has spread into the CNS concurrently with systemic disease or CNS relapse during or after frontline immunochemotherapy, presenting with or without systemic lymphoma. Diffuse large B-cell lymphoma (DLBCL) denotes the most common entity, but an increased incidence is observed in other histologies, such as Burkitt lymphoma and mantle-cell lymphoma. The incidence, timing in disease course, location, evidence supporting the use of CNS prophylaxis, and treatment pathways vary according to histology. No randomized data exist to delineate the best treatment approaches with current recommendations based on retrospective and single-arm studies. However, a regimen comprising immunochemotherapy, incorporating agents that cross the blood-brain barrier, followed by thiotepa-containing conditioning and autologous stem-cell transplant outlined in the international MARIETTA study demonstrated improvement in outcomes, representing a major accomplishment in the care of patients with DLBCL with SCNSL. Anti-CD19 chimeric antigen receptor T cell denotes a paradigm shift in the treatment of patients with systemic aggressive lymphomas, with emerging data also demonstrating efficacy without higher neurotoxicity in those with SCNSL. In this manuscript we discuss 5 clinical scenarios and review the evidence supporting our recommendations.

Analysis of False-negative Findings of the Incomparable Accuracy and Swiftness of Flow Cytometric Diagnosis of Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL), a relatively rare brain tumor, bears a dire prognosis. On occasion, the rapid progression of the tumor makes immediate diagnosis and initiation of therapy imperative. To achieve swift diagnosis, we adopt flow cytometry (FCM) in addition to conventional histopathology. This study aimed to reveal the utility of FCM diagnosis for PCNSL and the cause of false-negative results of FCM diagnosis. We investigated 33 patients with suspected PCNSL on neuroradiological findings and received both FCM and histological diagnosis. The patients' electronic medical records were investigated, and histological findings, results of FCM, and other clinical data were evaluated. Overall, 27 patients (14 males and 13 females) were diagnosed with PCNSL by histological confirmation. The median age at diagnosis was 68 years. FCM analysis showed lymphoma pattern in 24 cases; however, FCM results did not show lymphoma pattern (sensitivity: 88.9%, specificity: 100%) in the other three lymphoma cases (FCM discordant: FCM-D) and six nonlymphomatous tumor cases. Analysis of FCM-D cases showed the infiltration of T lymphocytes or astrocytes into the tumor tissue, indicating tumor microenvironmental reaction; it is assumed that these reactions deceived FCM diagnosis. The survival of FCM-D patients was superior to FCM concordant counterpart, although the difference was not significant (p = 0.459). The diagnosis of PCNSL by FCM is rapid and highly reliable. Some FCM-D cases are PCNSLs with strong tumor microenvironmental reactions.

Neurosarcoidosis: Diagnostic Challenges and Mimics A Review

PURPOSE OF REVIEW

Neurosarcoidosis is a rare manifestation of sarcoidosis that is challenging to diagnose. Biopsy confirmation of granulomas is not sufficient, as other granulomatous diseases can present similarly. This review is intended to guide the clinician in identifying key conditions to exclude prior to concluding a diagnosis of neurosarcoidosis.

RECENT FINDINGS

Although new biomarkers are being studied, there are no reliable tests for neurosarcoidosis. Advances in serum testing and imaging have improved the diagnosis for key mimics of neurosarcoidosis in certain clinical scenarios, but biopsy remains an important method of differentiation. Key mimics of neurosarcoidosis in all cases include infections (tuberculosis, fungal), autoimmune disease (vasculitis, IgG4-related disease), and lymphoma. As neurosarcoidosis can affect any part of the nervous system, patients should have a unique differential diagnosis tailored to their clinical presentation. Although biopsy can assist with excluding mimics, diagnosis is ultimately clinical.

Challenges in the management of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare extranodal non-Hodgkin lymphoma. Stereotactic biopsy remains the gold standard for the pathological diagnosis of PCNSL. However, certain new auxiliary diagnostic methods are considered to have good application prospects; these include cytokine and tumor circulating DNA, among others. Although new drugs such as immunomodulators, immune checkpoint inhibitors, chimeric antigen receptor T-cells, and Bruton tyrosine kinase inhibitors have brought hope owing to their improved efficacy, the high recurrence rate and subsequent high mortality remain barriers to long-term survival. Increasing emphasis is therefore being placed on consolidation treatments. Consolidation treatment strategies include whole brain radiotherapy, autologous hematopoietic stem cell transplantation, and non-myeloablative chemotherapy. As studies directly comparing the effectiveness and safety of different consolidation treatment schemes are lacking, the optimal consolidation strategy remains uncertain. This article will review the diagnosis and treatment of PCNSL, focusing on the progress in research pertaining to consolidation therapy.

Leptomeningeal Disease (LMD) in Patients with Melanoma Metastases

Leptomeningeal disease (LMD) is a devastating complication caused by seeding malignant cells to the cerebrospinal fluid (CSF) and the leptomeningeal membrane. LMD is diagnosed in 5-15% of patients with systemic malignancy. Management of LMD is challenging due to the biological and metabolic tumor microenvironment of LMD being largely unknown. Patients with LMD can present with a wide variety of signs and/or symptoms that could be multifocal and include headache, nausea, vomiting, diplopia, and weakness, among others. The median survival time for patients with LMD is measured in weeks and up to 3-6 months with aggressive management, and death usually occurs due to progressive neurologic dysfunction. In melanoma, LMD is associated with a suppressive immune microenvironment characterized by a high number of apoptotic and exhausted CD4⁺ T-cells, myeloid-derived suppressor cells, and a low number of CD8⁺ T-cells. Proteomics analysis revealed enrichment of complement cascade, which may disrupt the blood-CSF barrier. Clinical management of melanoma LMD consists primarily of radiation therapy, BRAF/MEK inhibitors as targeted therapy, and immunotherapy with anti-PD-1, anti-CTLA-4, and anti-LAG-3 immune checkpoint inhibitors. This review summarizes the biology and anatomic features of melanoma LMD, as well as the current therapeutic approaches.

Usefulness of Serum Soluble Interleukin-2 Receptor Levels for Differentiating between PCNSL and SCNSL

Serum soluble interleukin-2 receptor (sIL-2R) is a practical tumor marker that is elevated in hematogenous tumors. The purpose of this study was to determine the usefulness of serum sIL-2R for differentiating among malignant brain tumors, including primary central nervous system lymphoma (PCNSL) and secondary central nervous system lymphoma (SCNSL). This study retrospectively investigated the sIL-2R levels in 130 patients with various types of malignant brain tumors, including PCNSL patients (n = 48) and SCNSL (n = 8); metastatic brain tumors (MTs, n = 16); and glioblastoma (GBM, n = 58). The median sIL-2R level (U/mL) of the PCNSL, SCNSL, MTs, and GBM groups were 489.7, 1024.8, 413.3, and 332.7 respectively. The sIL-2R level was significantly higher in the SCNSL group than in the PCNSL or other groups. The area under the ROC curve generated from the sIL-2R level was 0.826 (sensitivity: 0.875, specificity: 0.667, cutoff value: 521 U/mL) for differentiating SCNSL from PCNSL and 0.685 (sensitivity: 0.667, specificity: 0.707, cutoff value: 342 U/mL) for differentiating PCNSL from GBM. Measurement of sIL-2R level was convenient and useful to differentiate between SCNSL and PCSNL, both of which demand different treatment strategies.

[A case of primary central nervous system lymphoma with marked cauda equina enlargement]

An 80-year-old woman presented with subacute right lower limb pain and bilateral lower limb weakness. MRI of the spine showed marked cauda equina enlargement with contrast enhancement. Cerebrospinal fluid (CSF) examination showed elevated cell count, decreased glucose, and elevated protein. Cytology of the CSF showed class V, which together with B-cell clonality by flow cytometry, led to the diagnosis of primary central nervous system lymphoma (PCNSL). The patient was treated with steroid, radiation, and chemotherapy. Despite the reduction in lesion size, her neurological symptoms revealed no improvement. PCNSL with cauda equina lesions are rare and often require highly invasive cauda equina biopsy for diagnosis. In recent years, some studies reported useful CSF biomarkers, but they may have some problems. Therefore, as in this case, the combination of cytology, flow cytometry and, CSF biomarkers could be a substitute method for invasive biopsies, and contribute to the early treatment of PCNSL.

Lymphomas mimicking neuroinflammatory diseases - A diagnostic conundrum worth revisiting

PURPOSE OF REVIEW

Central nervous system (CNS) lymphomas (CNSLs) have varied clinical presentations which can mimic neuroinflammatory disease, leading to a diagnostic dilemma for clinicians.

RECENT FINDINGS

This report describes two patients who initially received a diagnosis of neuroinflammatory disorders but were refractory to treatment over a protracted time course. In both cases, biopsy revealed diffuse large B cell lymphoma (DLBCL) as the final diagnosis.

SUMMARY

The analysis of these cases provides an opportunity for increased recognition of CNS lymphomas for earlier diagnosis and treatment. It also calls for increased clinical suspicion for CNSLs in such circumstances. And possibly the search for new biomarker development for identifying and tracking CNSLs.

Primary central nervous system lymphoma presenting as an isolated intramedullary spinal cord lesion: a case report

Background

Intramedullary spinal cord lesions prove to be a diagnostic challenge due to their non-specific clinical and radiological presentation. There is a preference for empiric medical therapy, given the inherent risks of surgical intervention to the spine. These factors can lead to delay in diagnosis. Primary central nervous system lymphoma is a rare cause and presents with atypical features in the immunosuppressed patient, including a lack of response to steroid therapy.

Case Description

We present a 64-year-old male patient with underlying sarcoidosis who reported progressive neuropathy with imaging showing a spinal cord lesion. Based on the above, multiple courses of empiric therapy were employed, including systemic steroids, chemotherapy and immunotherapy. Despite this, there was further clinical deterioration and interim imaging showed disease progression. The decision was made to perform open biopsy of the spinal cord lesion to aid diagnosis. Histological analysis diagnosed Epstein-Barr virus (EBV)-positive high grade large B-cell lymphoma. The patient received rituximab and methotrexate with radiological response but no clinical benefit. He continued to suffer treatment-related complications including encephalopathy and recurrent infections which eventually lead to death.

Conclusions

Primary central nervous system lymphoma is an aggressive disease and failure to respond to empiric treatment should prompt clinician's to consider biopsy for definitive diagnosis. A lack of response to steroids does not exclude lymphoma.

Clinical and magnetic resonance imaging features, and pathological findings of spinal lymphoma in 27 cats

This multicentric retrospective study describes the clinical and MRI features and pathological studies of spinal lymphoma in 27 cats. MRI characteristics and their possible correlations with histopathological findings were studied. The most frequent neurological signs were rapidly progressive paraparesis (62.9%) or paraplegia (22.2%). Bimodal age distribution was found with 40.7% of cats aged ≤2.5 years (63.6% of them FeLV positive), and 44.4% of cats aged ≥8 years (16.7% of them FeLV positive). Spinal lymphoma was generally presented on MRI as an ill-defined epidural focal lesion with moderate to severe spinal cord compression, expanding more than one vertebral body. MRI lesions were typically localized in the lumbar vertebral segment (p = 0.01), circumferential to the spinal cord (p = 0.04), hyperintense on T2-weighted sequences (p = 4.3e-06), and isointense on T1-weighted sequences (p = 8.9e-07). The degree and pattern of contrast enhancement were variable. Other morphological patterns included paravertebral masses with extension into the vertebral canal and lesions centered in the spinal nerve roots. Involvement of vertebrae and adjacent spinal soft tissues was present in 74% of cases when present vertebral involvement was characterized by cortical sparing. When follow-up MRI studies (n = 4) were performed after treatment new lesions of similar nature but different localizations and extension were observed. Confirmation of spinal lymphoma was performed by CSF analysis in 4/27 (14.8%) of cases, by FNA in 6/27 (22.2%) of cases, by surgical biopsy in 10/27 (37%) of cases, by FNA and surgical biopsy in 1/27 (3.7%) of cases, by CSF, FNA, surgical biopsy and postmorten examination in 1/27 (3.7%) of cases, and postmorten studies in 5/27 (18.5%) of cases. Antemortem diagnosis was achieved in 22/27 (81.5%) cats. The presence of necrosis in histopathological studies as an unfavorable prognostic indicator of survival was significantly more probable when lesions were not hyperintense on T2-weighted sequences (p = 0.017). Spinal lymphoma in cats is a complex entity with heterogeneous imaging and histopathological appearance. However, certain MRI features may support a tentative diagnosis, which in a group of cases can be confirmed when combined with the CSF findings. For the rest of the cases, tissue sampling assisted by imaging findings remains necessary for definitive diagnosis.

Neurosarcoidosis: Phenotypes, Approach to Diagnosis and Treatment

PURPOSE OF REVIEW

The aim of this review is to provide an update of clinical presentation, diagnosis, differential diagnoses, and treatment according to recent evidence.

RECENT FINDINGS

Neurosarcoidosis remains a diagnosis of exclusion, with infectious and malignant etiologies recognized as important mimickers. Corticosteroids remain as first-line therapy. In recent years, however, studies have demonstrated the effectiveness of anti-tumor necrosis factor (anti-TNF) therapy in the treatment of neurosarcoidosis, leading to improved outcomes. Neurosarcoidosis is a granulomatous disease with protean manifestations that may affect any part of the central and peripheral nervous system. It has many mimickers, and potentially devastating complications necessitating long-term follow-up. Early initiation of treatment, particularly with anti-TNF therapy, may lead to better outcomes and fewer relapses. There is an unmet need for randomized controlled trials that provide robust data to guide therapy and the long-term management of neurosarcoidosis patients.

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.

Circulating microRNAs in Cerebrospinal Fluid and Plasma: Sensitive Tool for Detection of Secondary CNS Involvement, Monitoring of Therapy and Prediction of CNS Relapse in Aggressive B-NHL Lymphomas

Simple Summary

Lymphoma involving the central nervous system and CNS relapse present diagnostic and predictive challenges. Its diagnosis is based on conventional methods with low sensitivity and/or specificity. More powerful tools for its early detection, response evaluation, and CNS relapse prediction are needed. MicroRNAs are short post-transcriptional gene regulators that are remarkably stable and detectable extracellularly in body fluids. We evaluated the diagnostic and predictive potential of circulating oncogenic microRNAs (oncomiRs) in CSF and plasma for the detection of secondary CNS involvement in aggressive B-NHL lymphomas, as well as for detection and prediction of their CNS relapse. Our findings indicate that the evaluation of oncogenic microRNAs in CSF and plasma potentially provides a sensitive tool for the early detection of secondary CNS lymphoma, the monitoring and estimating of treatment efficacy, and the prediction and early detection of CNS relapse.

Abstract

Lymphoma with secondary central nervous system (CNS) involvement represents one of the most aggressive malignancies, with poor prognosis and high mortality. New diagnostic tools for its early detection, response evaluation, and CNS relapse prediction are needed. We analyzed circulating microRNAs in the cerebrospinal fluid (CSF) and plasma of 162 patients with aggressive B-cell non-Hodgkin’s lymphomas (B-NHL) and compared their levels in CNS-involving lymphomas versus in systemic lymphomas, at diagnosis and during treatment and CNS relapse. We identified a set of five oncogenic microRNAs (miR-19a, miR-20a, miR-21, miR-92a, and miR-155) in CSF that detect, with high sensitivity, secondary CNS lymphoma involvement in aggressive B-NHL, including DLBCL, MCL, and Burkitt lymphoma. Their combination into an oncomiR index enables the separation of CNS lymphomas from systemic lymphomas or nonmalignant controls with high sensitivity and specificity, and high Receiver Operating Characteristics (DLBCL AUC = 0.96, MCL = 0.93, BL = 1.0). Longitudinal analysis showed that oncomiR levels reflect treatment efficacy and clinical outcomes, allowing their monitoring and prediction. In contrast to conventional methods, CSF oncomiRs enable detection of early and residual CNS involvement, as well as parenchymal involvement. These circulating oncomiRs increase 1–4 months before CNS relapse, allowing its early detection and improving the prediction of CNS relapse risk in DLBCL. Similar effects were detectable, to a lesser extent, in plasma.

Diagnosis, treatment, and outcome of primary CNS lymphoma-a single-center experience

BACKGROUND

Primary CNS lymphoma (PCNSL) is a highly aggressive non-Hodgkin lymphoma (NHL) that occurs in the CNS (e.g. brain, meninges, spinal cord, cerebrospinal fluid, or intraocular involvement) in the absence of systemic NHL. Tumor resection does not improve survival, and neurosurgical intervention is generally limited to stereotactic biopsy to provide a histopathological diagnosis.

OBJECTIVE

The objective of this single-center study was to evaluate the management and outcome of PCNSL patients diagnosed by biopsy, using overall survival and progression-free survival as endpoints.

METHODS

At our department of neurosurgery, 140 patients were diagnosed with PCNSL by biopsy between January 1, 2009, and December 31, 2018. Of these, 37 patients were included in the study and were divided into three groups according to their postoperative therapy.

RESULTS

Median OS was 35.7 months for the intensive treatment group, 29.5 months for the moderate treatment group, and 8.6 months for the palliative treatment group. The intensive and moderate treatment groups had similar progression-free survival, while the palliative treatment group had poor overall and progression-free survival. Six patients were long-term survivors (> 80 months). Age under 65 years was the main significant parameter affecting overall survival.

CONCLUSION

In this cohort, patients with PCNSL had an overall fair prognosis if they (1) were under 65 years old, (2) had a performance score < 2 at the time of diagnosis, and (3) received either intensive or moderate chemotherapeutic treatment. Biopsy is still the primary diagnostic tool; other methods have been investigated but are not yet recommended.

Rare central nervous system lymphomas

Central nervous system (CNS) lymphomas are rare malignancies characterised by lymphoid infiltration into the brain, spinal cord, cranial nerves, meninges and/or eyes in the presence or absence of previous or concurrent systemic disease. Most CNS lymphomas are of the diffuse large B-cell lymphoma (DLBCL) subtype for which treatment strategies, particularly the use of high-dose methotrexate-based protocols and consolidation with autologous stem cell transplantation, are well established. Other histopathological subtypes of CNS lymphoma are comparatively less common with published data on these rare lymphomas dominated by smaller case series and retrospective reports. Consequently, there exists little clinical consensus on the optimal methods to diagnose and manage these clinically and biologically heterogeneous CNS lymphomas. In this review article, we focus on rarer CNS lymphomas, summarising the available clinical data on incidence, context, diagnostic features, reported management strategies, and clinical outcomes.

Branch-like enhancement on contrast enhanced MRI is a specific finding of cerebellar lymphoma compared with other pathologies

Branch-like enhancement (BLE) on contrast-enhanced (CE) magnetic resonance imaging (MRI) was found to be effective in differentiating primary central nervous system lymphoma (PCNSL) from high-grade glioma (HGG) in the cerebellum. However, whether it can be applied to assessments of secondary central nervous system lymphoma (SCNSL), or other cerebellar lesions is unknown. Hence, we retrospectively reviewed cerebellar masses to investigate the use of BLE in differentiating cerebellar lymphoma (CL), both primary and secondary, from other lesions. Two reviewers qualitatively evaluated the presence and degree of BLE on CE-T1 weighted imaging (T1WI). If multiple views were available, we determined the view in which BLE was the most visible. Seventy-five patients with the following pathologies were identified:17 patients with CL, 30 patients with metastasis, 12 patients with hemangioblastoma, 9 patients with HGG, and 7 patients with others. Twelve patients presented with PCNSL and five with SCNSL. Of 17 patients with CL, 15 (88%) had BLE, whereas three (5%) out of 58 patients in the non-CL group showed BLE. In patients who underwent three-dimensional-CE-T1WI, BLE was the most visible on the sagittal image. In conclusion, BLE is a highly specific finding for CL and the sagittal image is important in evaluating this finding.

Primary Diffuse Large B Cell Lymphoma of Bone: A Single-Center Experience

Background

Primary diffuse large B-cell lymphoma of the bone (PB-DLBCL) is a rare type of extra-nodal lymphoma. This study aimed to examine the clinical characteristics, outcomes, treatment modalities and risk of central nervous system relapse (CNSR) among adult Jordanian patients with PB-DLBCL.

Methods

This retrospective study included patients aged >16 years who were diagnosed with PB-DLBCL and treated at our hospital between 2002 and 2021. Clinical characteristics, treatment modalities, outcomes and CNSR events were extracted from the hospital’s data system and analysed. Patients were categorised into unifocal (UF) and multifocal (MF) PB-DLBCL groups according to the number of bone sites involved. The involvement of only one site was defined as UF, whereas the involvement of two or more sites was defined as MF.

Results

In total, 12 patients were diagnosed with PB-DLBCL. Their median age was 47.5 years (range, 17–80 years). The male:female ratio was 1:1. There were eight patients in the UF PB-DLBCL group and four in the MF PB-DLBCL group. All patients received treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone. In the UF PB-DLBCL group, the male:female ratio was 5:3, the median age was 41 years, and the follow-up duration was 9–135 (mean, 83.3) months. In the MF PB-DLBCL group, the male:female ratio was 1:3, the median age was 51.5 years, and the survival time was 3–11 (mean, 7) months. Three patients with vertebral UF PB-DLBCL underwent early vertebroplasty without complications. The most common site involved was the vertebral column. Most patients with UF PB-DLBCL achieved complete remission (CR), whereas no patients with MF PB-DLBCL achieved CR.

Conclusion

PB-DLBCL is rare in adult Jordanian patients. UF PB-DLBCL is more common than MF PB-DLBCL. Patients with UF PB-DLBCL had a good prognosis. Patients with MF PB-DLBCL had a high international prognostic index score, risk of CNSR and short survival time.

[Central nervous system involvement of graft versus host disease after allogeneic hematopoietic stem cell transplantation for adult T cell leukemia]

A 54-year-old woman was diagnosed with acute adult T-cell leukemia (ATL) in November 2015 and underwent allogeneic hematopoietic stem cell transplantation in March 2016. Cognitive impairment appeared suddenly around May 2019, and MRI of the brain showed cerebral white matter lesions. Cerebrospinal fluid examination showed no significant findings other than elevated protein. Brain biopsy showed inflammatory cells, (mainly CD8-positive T lymphocytes), infiltrating the white matter. Based on the pathological findings and the history of chronic graft versus host disease (GVHD) in the lungs and intestines, we diagnosed central nervous system involvement of GVHD (CNS-GVHD). Immunotherapy with steroids and mycophenolate mofetil resulted in improvement of the cognitive dysfunction and inflammatory findings in the spinal fluid. This case is the first report of CNS-GVHD in ATL, suggesting the importance of diagnosis by brain biopsy and the efficacy of immunotherapy.

Primary Leptomeningeal B-cell Lymphoma in an Immunocompetent Adult: Case Report

Primary leptomeningeal lymphoma (PLML) is a rare disease, comprising less than 1% of all lymphomas. Clinical manifestations include headache, encephalopathy, ataxia, cranial nerve palsy, and myelitis. Diagnosis requires a combination of magnetic resonance images (MRI), cytology, flow cytometry of cerebrospinal fluid (CSF), and an extensive workup to rule out systemic lymphoma.

We describe the case of a 49-year-old man who developed subacute onset headache, encephalopathy, and blindness. Whole-body examinations, including a bone marrow trephine biopsy, excluded systemic lymphoma. Brain MRI showed leptomeningeal enhancement. Cytology and flow cytometry of CSF found a clonal B-cell population making a diagnosis of PLML. He began treatment with rituximab and high-dose methotrexate (HD-MTX), with progressive clinical improvement. CSF analysis after two cycles and one intrathecal methotrexate dose was normal.

Brain and spinal MRI images plus CSF analysis, along with an extensive workup to exclude systemic lymphoma, are necessary to diagnose PLM. Early treatment with HD-MTX alone or in combination with rituximab improves clinical outcomes.

An Unusual Case of Concurrent Herpes Simplex Virus Type 1 and Cytomegalovirus Encephalitis Complicated by Primary Central Nervous System Lymphoma as an Initial Presentation of Acquired Immunodeficiency Syndrome

Primary central nervous system lymphoma (PCNSL) is an uncommon brain tumor with a puzzling diagnosis. It has an incidence of seven cases per 100,000,000 people in the United States, which is further lower in immunocompromised patients. Cytomegalovirus (CMV) is a common cause of various malignancies, notably Burkitt’s lymphoma, nasopharyngeal carcinoma, Hodgkin’s lymphomas, and non-Hodgkin’s lymphomas (NHL) including PCNSL. Cases with PCNSL can vary in presentation with either focal or non-focal manifestations progressively worsening over a period that could last up to a few months. In this report, we discuss the case of a 39-year-old woman with a past medical history of bipolar disorder who presented with PCNSL as the initial presentation of acquired immunodeficiency syndrome (AIDS). This case report emphasizes the importance of a multidisciplinary team (MDT) approach for the interpretation as well as for correlating the laboratory and imaging results with clinical findings given the challenging diagnosis, to choose an appropriate management approach that is tailored to the patient's presentation.

Approach to Altered Mental Status and Inpatient Delirium

Altered mental status is a nonspecific diagnosis that encompasses a wide spectrum of disease and is frequently cited as a reason for both hospital admission and inpatient neurologic consultation. There are numerous etiologies of altered mental status, and so although many are facile with the workup of this potentially life-threatening entity, it can nevertheless be overwhelming. Our goal was to provide a practical framework embedded in a current, comprehensive review of the epidemiology, clinical evaluation, and management of undifferentiated altered mental status. We pay particular attention to the management of a critical yet underdiagnosed subtype of altered mental status: delirium.

[A case of primary intramedullary spinal cord lymphoma diagnosed by spinal cord biopsy of long spinal cord lesions showing persistent gadolinium contrast enhancement]

An 82-year-old man presented with subacute bilateral lower limb paralysis, deep sensory disturbance, and vesico-rectal disturbance. MRI of the spinal cord revealed a large gray matter-dominant lesion extending from the medulla oblongata to the lower thoracic spinal cord. The patient was treated with steroid-pulse therapy for myelitis, but without symptomatic improvement. A spinal cord biopsy was performed for treatment-resistant myelopathy, and histopathology revealed a diffuse large B-cell lymphoma, that was diagnosed as a primary intramedullary spinal cord lymphoma because systemic examination didn't show any other findings suggestive of malignant lymphoma. A spinal cord biopsy is necessary for the definitive diagnosis of this disease, but in the case of poor response to treatment and a progressive course, intramedullary malignant lymphoma should be considered if there is a persistent elevation of CSF IL-10 or a prolonged contrast effect.

Detection of Neoplasms by Metagenomic Next-Generation Sequencing of Cerebrospinal Fluid

Importance

Cerebrospinal fluid (CSF) cytologic testing and flow cytometry are insensitive for diagnosing neoplasms of the central nervous system (CNS). Such clinical phenotypes can mimic infectious and autoimmune causes of meningoencephalitis.

Objective

To ascertain whether CSF metagenomic next-generation sequencing (mNGS) can identify aneuploidy, a hallmark of malignant neoplasms, in difficult-to-diagnose cases of CNS malignant neoplasm.

Design, Setting, and Participants

Two case-control studies were performed at the University of California, San Francisco (UCSF). The first study used CSF specimens collected at the UCSF Clinical Laboratories between July 1, 2017, and December 31, 2019, and evaluated test performance in specimens from patients with a CNS malignant neoplasm (positive controls) or without (negative controls). The results were compared with those from CSF cytologic testing and/or flow cytometry. The second study evaluated patients who were enrolled in an ongoing prospective study between April 1, 2014, and July 31, 2019, with presentations that were suggestive of neuroinflammatory disease but who were ultimately diagnosed with a CNS malignant neoplasm. Cases of individuals whose tumors could have been detected earlier without additional invasive testing are discussed.

Main Outcomes and Measures

The primary outcome measures were the sensitivity and specificity of aneuploidy detection by CSF mNGS. Secondary subset analyses included a comparison of CSF and tumor tissue chromosomal abnormalities and the identification of neuroimaging characteristics that were associated with test performance.

Results

Across both studies, 130 participants were included (median [interquartile range] age, 57.5 [43.3-68.0] years; 72 men [55.4%]). The test performance study used 125 residual laboratory CSF specimens from 47 patients with a CNS malignant neoplasm and 56 patients with other neurological diseases. The neuroinflammatory disease study enrolled 12 patients and 17 matched control participants. The sensitivity of the CSF mNGS assay was 75% (95% CI, 63%-85%), and the specificity was 100% (95% CI, 96%-100%). Aneuploidy was detected in 64% (95% CI, 41%-83%) of the patients in the test performance study with nondiagnostic cytologic testing and/or flow cytometry, and in 55% (95% CI, 23%-83%) of patients in the neuroinflammatory disease study who were ultimately diagnosed with a CNS malignant neoplasm. Of the patients in whom aneuploidy was detected, 38 (90.5%) had multiple copy number variations with tumor fractions ranging from 31% to 49%.

Conclusions and Relevance

This case-control study showed that CSF mNGS, which has low specimen volume requirements, does not require the preservation of cell integrity, and was orginally developed to diagnose neurologic infections, can also detect genetic evidence of a CNS malignant neoplasm in patients in whom CSF cytologic testing and/or flow cytometry yielded negative results with a low risk of false-positive results.

Optic Nerve Infiltration in Systemic Lymphoma in an HIV Patient

Different mechanisms have been proposed in lymphomatous involvement of the optic nerve. They include isolated optic nerve lymphoma, optic nerve lymphoma associated with primary central nervous system (CNS) lymphoma, or with systemic lymphoma. We present one case of non-Hodgkin lymphoma of the optic nerve in a Human Immunodeficiency Virus (HIV) patient and discuss the mechanism of metastasis, classification of optic nerve involvement with clinical and radiologic features as well as treatment options. Despite the uncommon nature of optic nerve infiltration by lymphoma, prompt evaluation should be considered in patients with a history of lymphoma and visual symptoms as delays in treatment can result in permanent vision loss. The recommended initial workup includes neuroimaging and cerebrospinal fluid evaluation. Treatment options are not standardized but include intravenous and intrathecal chemotherapy, corticosteroids, and radiation.

Body CT and PET/CT Detection of Extracranial Lymphoma in Patients with Newly Diagnosed Central Nervous System Lymphoma

BACKGROUND

We aimed to investigate the detection rate of body CT or PET/CT for sites of extracranial disease in patients with a new pathological diagnosis of CNS DLBCL and to identify factors associated with sites of extracranial disease.

METHODS

An international multicenter cohort study of consecutive immunocompetent patients with a new diagnosis of CNS DLBCL confirmed by brain biopsy who underwent CT and/or PET/CT to evaluate for sites of extracranial disease between 1998 and 2019. The primary outcome was the detection rate of extracranial lymphoma by CT or PET/CT. Subgroup analyses according to age and EBV status were also performed. Logistic regression analyses were performed to determine factors related to sites of extracranial disease. Detection rates of CT and PET/CT were compared.

RESULTS

1043 patients were included. The overall detection rate of CT or PET/CT was 2.6% (27/1043). The treatment approach was adjusted in 74% of these patients. Multivariable analysis demonstrated that age>61-years (OR, 3.10; P=.016) and EBV positivity (OR, 3.78; P=.045) were associated with greater odds of extracranial lymphoma. There was no statistically significant difference in detection rate between CT and PET/CT (P=.802). In patients≤61 years old, the false-referral rates were significantly higher than the detection rates (P<.001).

CONCLUSION

Our results showed increased odds of extracranial lymphoma in patients with older age or EBV-positive lymphoma. Treatment was adjusted in a majority of patients diagnosed with extracranial lymphoma, thereby supporting the current guidelines for the use contrast-enhanced body CT or PET/CT in patients with newly diagnosed CNS DLBCL.

MicroRNAs as Diagnostic Biomarkers in Primary Central Nervous System Lymphoma: A Systematic Review and Meta-Analysis

Background

Diagnosing primary central nervous system lymphoma (PCNSL) remains a challenge. MicroRNAs (miRNAs) are promising noninvasive markers for the identification of PCNSL. The present study aims to assess the diagnostic value of miRNAs for PCNSL patients as biomarkers.

Methods

We systematically searched PubMed, Embase, and the Cochrane library from inception to January 31, 2021. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), together with the summary receiver operator characteristic (SROC) curve, and the area under the SROC curve (AUC) value were used to estimate the overall diagnostic performance. We used Q statistic and I² to test heterogeneity and used subgroup analyses to investigate the source of heterogeneity. The statistical analyses were independently performed by two investigators using Stata 14.0 and Revman 5.3.

Results

In total, 11 studies from 6 records were included in the current meta-analysis with 281 PCNSL patients and 367 controls. Our statistical analysis demonstrated that the pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0.91 (95% CI 0.84–0.95), 0.88 (95% CI 0.84–0.91), 7.48 (95% CI 5.71–9.78), 0.11 (95% CI 0.06–0.19), 70 (95% CI 35–142), and 0.90 (95% CI 0.87–0.92), respectively. The studies had substantial heterogeneity (I² = 54%, 95% CI 0–100). Two subgroup analyses were conducted based on the type of specimen and miRNAs profiled.

Conclusions

This meta-analysis indicated that miRNAs were suitable as noninvasive diagnostic biomarkers for PCNSL with high accuracy. In addition, both cerebrospinal fluid-based and blood-based miRNAs assays for PCNSL detection were considered reliable for clinical application. MicroRNA-21 assays also seemed to be more accurate in the diagnosis of PCNSL. Good quality studies with large samples should be conducted to verify our results.

Treatment of Primary CNS Lymphoma: Maximizing Clinical Benefit, Minimizing Neurotoxicity

PURPOSE OF REVIEW

The optimal treatment for newly diagnosed and refractory or relapsed primary central nervous system lymphoma (PCNSL) is not fully defined. We review the epidemiology, clinical presentation, and current management strategies for newly diagnosed PCNSL as well as emerging treatments for refractory and relapsed disease.

RECENT FINDINGS

In recent decades, the incidence of PCNSL has increased in the elderly population. With advancements in chemotherapy for PCNSL, survival has improved. However, outcomes remain inferior when compared with other forms of extranodal lymphoma. Additionally, treatments can be associated with clinically significant neurotoxicities. Despite advances in the treatment of PCNSL, current treatment regimens remain suboptimal in terms of response rates and neurotoxicity. Well-tolerated agents, especially for the elderly, are still needed.

Primary peripheral T-cell central nervous system lymphoma

BACKGROUND

Primary peripheral T-cell central nervous system lymphoma (PCNSL) is a rare, aggressive tumor that arises in the craniospinal axis and has an increased risk in individuals who are immunocompromised. This lesion often mimics other benign and malignant processes on radiographic imaging, leading to misdiagnosis and delays in treatment. We present a case of a patient with a history of Sjögren's syndrome and progressive neurologic symptoms who underwent craniotomy for diagnosis.

CASE DESCRIPTION

A 61-year-old woman with a history of Sjögren's syndrome, progressive aphasia, left facial droop, and right-sided paresthesias for 4 months presented for evaluation and management. An enhancing, infiltrative lesion in the left frontal lobe with underlying vasogenic edema was appreciated and suggestive of a primary or metastatic neoplasm. The patient underwent an open biopsy for further evaluation of the lesion. Extensive histopathologic evaluation revealed a diagnosis of T-cell PCNSL. The patient was started on induction methotrexate and temozolomide followed by consolidative radiotherapy.

CONCLUSION

Autoimmune conditions are a risk factor for T-cell PCNSL development. T-cell PCNSL has radiographic and gross histologic features that are consistent with a broad differential, including gliomas and inflammatory processes. Prompt diagnosis and extensive histopathological evaluation is essential to ensure appropriate treatment.

Cerebral Microvascular Erdheim-Chester Disease: A Perivascular Hematopoietic Vasculopathy

Erdheim-Chester disease (ECD) is a rare and elusive hematopoietic malignancy that may involve the nervous system in various ways. Cerebrovascular ECD involves the perivascular infiltration and compromise of any cervicocranial vessel by transformed proliferating histiocytes. Presented is the novel case of a patient with pathologically proven perivascular microangiopathy, manifesting in multifaceted fashion with ischemia, hemorrhage, mass lesions, and edema.

Clinical utility of brain biopsy for presumed CNS relapse of systemic lymphoma

OBJECTIVE

The objective of this study was to determine the frequency with which brain biopsy for presumed CNS relapse of systemic hematological malignancies yields new, actionable diagnostic information. Hematological malignancies represent a disparate group of genetic and histopathological disorders. Proclivity for brain involvement is dependent on the unique entity and may occur synchronously or metasynchronously with the systemic lesion. Diffuse large B-cell lymphomas (DLBCLs) have a high propensity for brain involvement. Patients in remission from systemic DLBCL may present with a lesion suspicious for brain relapse. These patients often undergo brain biopsy. The authors' a priori hypothesis was that brain biopsy in patients with a history of systemic DLBCL and a new brain MRI lesion would have lower diagnostic utility compared with patients with non-DLBCL systemic malignancies.

METHODS

The authors performed a retrospective review of patients who underwent brain biopsy between 2000 and 2019. Inclusion criteria were patients ≥ 18 years of age with a prior systemic hematological malignancy in remission presenting with a new brain MRI lesion concerning for CNS relapse. Patients with a history of any CNS neoplasms, demyelinating disorders, or active systemic disease were excluded. The main outcome was the proportion of patients with a distinct histopathological brain diagnosis compared with the systemic malignancy. The authors secondarily assessed overall survival, procedure-related morbidity, and 30-day mortality.

RESULTS

Sixty patients met inclusion criteria (40 males and 20 females); the median age at brain biopsy was 67 years (range 23-88 years). The median follow-up was 8.5 months (range 0.1-231 months). Thirty-nine (65.0%) patients had DLBCL and 21 (35%) had non-DLBCL malignancies. Thirty-five of 36 (97.2%) patients with prior systemic DLBCL and a diagnostic biopsy had histopathological confirmation of the original systemic disease versus 0 of 21 patients with non-DLBCL systemic malignancies (p < 0.001). Morbidity and 30-day mortality were 8.3% and 10.0%, respectively; 2 of 6 30-day mortalities were directly attributable to the biopsy. The median overall survival following brain biopsy was 10.8 months.

CONCLUSIONS

Patients with a history of systemic DLBCL and presumed CNS relapse gained minimal clinical benefit from brain biopsy but were at high risk of morbidity and mortality. In patients with a history of non-DLBCL systemic malignancies, brain biopsy remained critical given the high likelihood for discovery of distinct diagnostic entities. It was determined that patients with a prior systemic DLBCL and presumed brain relapse should likely receive empirical therapy obviating treatment delay and the risks of brain biopsy.

Cerebrospinal Fluid Flow Cytometry: Utility in Central Nervous System Lymphoma Diagnosis

BACKGROUND

Flow cytometry of the cerebrospinal fluid (CSF) is used in isolation or as an adjunct to cytology to increase the sensitivity of detecting central nervous system (CNS) lymphoma. We aimed to evaluate the sensitivity of CSF flow cytometry as a diagnostic screening tool for primary CNS lymphoma in patients presenting with undifferentiated neurologic symptoms.

METHODS

We retrospectively reviewed all CSF samples received by the Calgary Laboratory Services Flow Cytometry Laboratory from 2012 to 2015. Clinical data, laboratory investigations, radiologic imaging studies, and pathological data were analyzed. Clinical review extended to 2 years post-CSF flow cytometric testing.

RESULTS

Only 43/763 (5.6%) samples of CSF flow cytometry in 28/573 (4.9%) patients were found to be positive for a hematological malignancy in patients with undifferentiated neurologic symptoms. The overall sensitivity of the test was 13.8% with 25 patients with negative CSF flow cytometry later having a positive biopsy for CNS lymphoma. CSF flow cytometry was negative in all cases when at the time of CSF examination the patient did not have a previous hematological malignancy or findings of abnormal enhancement on MRI (n = 249).

CONCLUSION

CSF flow cytometry has low utility in screening for primary CNS lymphoma in the absence of a previous history of hematologic malignancy or findings of abnormal enhancement on MRI.

The value of bone marrow biopsy for staging of patients with primary CNS lymphoma

BACKGROUND

In patients with presumed primary CNS lymphoma (PCNSL) a systemic manifestation is found only in a small minority. Although bone marrow biopsy (BMB) is recommended for staging, its diagnostic value is unclear.

METHODS

A retrospective analysis of 392 patients with presumed PCNSL from three university hospitals and 33 patients with secondary CNS lymphoma (SCNSL) and initial CNS involvement from a multicentre Germany-wide prospective registry was performed.

RESULTS

A BMB was performed and documented in 320/392 patients with presumed PCNSL; 23 had pathologic results. One harboured the same lymphoma in the brain and bone marrow (BM), 22 showed findings in BM discordant to the histology of brain lymphoma; n=12 harboured a low grade lymphoma in the bone marrow, the other showed B-cell proliferation but no proof of lymphoma (n=5), monoclonal B-cells (n=3) or abnormalities not B-cell associated (n=2). In the group of SCNSL with initial CNS manifestation 32/33 patients underwent BMB; seven were documented with bone marrow involvement (BMI); one had concordant results in the brain and bone marrow with no other systemic manifestation. Six had additional systemic lymphoma manifestations apart from the brain and bone marrow.

CONCLUSIONS

In only two out of 352 (0.6%) patients with CNS lymphoma (320 presumed PCNSL and 32 SCNSL) BMB had an impact on diagnosis and treatment. While collected in a selected cohort these findings challenge the value of BMB as part of routine staging in presumed PCNSL.

Diagnosis, prognosis and treatment of primary central nervous system lymphoma in the elderly population (Review)

Primary central nervous system lymphoma (PCNSL) is a rare subtype of extranodal non-Hodgkin lymphoma that is unique and different from systemic diffuse large B-cell lymphomas. The median age at diagnosis of PCNSL is 65 years and its incidence is rising rapidly in the elderly population. A total of ≥20% of all patients with PCNSL are ≥80 years old. Notably, age has been identified as an independent poor prognostic factor for PCNSL. Elderly patients have an inferior prognosis to that of younger patients and are more severely affected by iatrogenic toxicity; therefore, elderly patients represent a unique and vulnerable treatment subgroup. The present review summarized the available literature to provide an improved understanding of the epidemiology, clinical characteristics, diagnosis, prognosis and management of PCNSL in the elderly population. Notably, the incidence of PCNSL in immunocompetent elderly patients, predominantly in men, is increasing. For the diagnosis of CNSL, imaging-guided stereotactic biopsy is considered the gold standard. When stereotactic biopsy is not possible or conclusive, certain biomarkers have been described that can help establish a diagnosis. PCNSL has a very poor prognosis in the elderly, even though several prognostic scoring systems exist and several prognostic markers have been reported in patients with PCNSL. Furthermore, the treatment of elderly patients remains challenging; it is unlikely that a novel agent could be used as a curative monotherapy; however, a combination of novel agents with polychemotherapy or its combination with other novel drugs may have therapeutic potential.