Prognostic markers for immunodeficiency-associated primary central nervous system lymphoma

Primary central nervous system lymphoma: A mirror type presentation in an immunocompetent patient

Background

Primary central nervous system (CNS) lymphoma is a very rare extranodal non-Hodgkin lymphoma. The bilateral pattern, as we call it "mirror type", has been identified in other CNS lesions such as gliomas, metastases, and demyelinating lesions, so the differential diagnosis includes imaging studies such as magnetic resonance imaging contrasted with spectroscopy, ruling out immunodeficiency or metastatic disease.

Case Description

A 65-year-old female presented progressing headache, loss of memory and language alterations, as well as sensory alterations. Neuroimaging showed the presence of two equidistant periventricular lesions at the level of both ventricular atria, a spectroscopy study suggestive of malignancy. Serological studies showed no evidence of immunodeficiency or the presence of positive tumor markers; however, a biopsy was performed, which revealed a histopathological result of primary lymphoma of the CNS.

Conclusion

In neuro-oncology, primary CNS tumors with multiple lesions are rare, even more, the "mirror type" lesions. Lymphomas are lesions that can present in different ways on imaging and clinical presentation. These tumors that present a vector effect due to their size, perilesional edema, or that lead to loss of neurological function are highly discussed in diagnostic and surgical treatment. Due to their prognosis, action on diagnosis and treatment must be taken as quickly as hospital resources allow.

Coexisting of Primary Central Nervous System Lymphoma and Talaromyces marneffei Brain Abscess in an AIDS Patient, A Case Report and Review of the Literature

Background

Talaromyces marneffei is prevalent in South Asia. Latent Talaromyces marneffei infection of travellers make the diagnosis difficult. There are similarities in clinical manifestations between Talaromyces marneffei infection and lymphoma. Brain abscess is a rare form of Talaromyces marneffei infection.

Case Presentation

We reported a very rare case of a 19-year-old man with HIV infection who suffered from a brain mass and lymphadenopathy. His blood culture, bone marrow culture and sputum culture all grew Talaromyces marneffei. One month after treatment with voriconazole, the symptoms improved except brain mass. Surgical incision of the brain mass showed a compact mass, and pathological analysis showed the coexisting Talaromyces marneffei abscess and lymphoma. The patient is currently in a stable condition after receiving antifungal therapy and chemotherapy.

Conclusion

Based on a case report of a traveller who suffered from a brain mass of Talaromyces marneffei abscess and lymphoma after a visit to an endemic area, this review summarized the cases where there was confusion between lymphoma and the brain abscess of Talaromyces marneffei. Talaromyces marneffei infection can be found globally due to the increasing number of international travels. Talaromyces marneffei infection and lymphoma had similar characteristics which is easy to misdiagnose in clinic. Infection may also be accompanied by tumors, especially in patients infected with HIV. The manifestations and imaging of brain abscess of Talaromyces marneffei were not characteristic in different patients.

Integrated genetic analyses of immunodeficiency-associated Epstein-Barr virus- (EBV) positive primary CNS lymphomas

Immunodeficiency-associated primary CNS lymphoma (PCNSL) represents a distinct clinicopathological entity, which is typically Epstein-Barr virus-positive (EBV+) and carries an inferior prognosis. Genetic alterations that characterize EBV-related CNS lymphomagenesis remain unclear precluding molecular classification and targeted therapies. In this study, a comprehensive genetic analysis of 22 EBV+ PCNSL, therefore, integrated clinical and pathological information with exome and RNA sequencing (RNASeq) data. EBV+ PCNSL with germline controls carried a median of 55 protein-coding single nucleotide variants (SNVs; range 24-217) and 2 insertions/deletions (range 0-22). Genetic landscape was largely shaped by aberrant somatic hypermutation with a median of 41.01% (range 31.79-53.49%) of SNVs mapping to its target motifs. Tumors lacked established SNVs (MYD88, CD79B, PIM1) and copy number variants (CDKN2A, HLA loss) driving EBV- PCNSL. Instead, EBV+ PCNSL were characterized by SOCS1 mutations (26%), predicted to disinhibit JAK/STAT signaling, and mutually exclusive gain-of-function NOTCH pathway SNVs (26%). Copy number gains were enriched on 11q23.3, a locus directly targeted for chromosomal aberrations by EBV, that includes SIK3 known to protect from cytotoxic T-cell responses. Losses covered 5q31.2 (STING), critical for sensing viral DNA, and 17q11 (NF1). Unsupervised clustering of RNASeq data revealed two distinct transcriptional groups, that shared strong expression of CD70 and IL1R2, previously linked to tolerogenic tumor microenvironments. Correspondingly, deconvolution of bulk RNASeq data revealed elevated M2-macrophage, T-regulatory cell, mast cell and monocyte fractions in EBV+ PCNSL. In addition to novel insights into the pathobiology of EBV+ PCNSL, the data provide the rationale for the exploration of targeted therapies including JAK-, NOTCH- and CD70-directed approaches.

Study on primary central nervous system lymphoma in pediatric patients

BACKGROUND

Primary central nervous system lymphoma (PCNSL) in pediatric patients presents diagnostic and treatment challenges, leading to delays and suboptimal strategies. Moreover, PCNSL in immunocompetent pediatric patients is rarely reported. This retrospective study aimed to describe the demographic and clinical features, as well as outcomes, of pediatric PCNSL cases.

METHODS

A retrospective review was conducted on 11 immunocompetent pediatric patients diagnosed with PCNSL between January 2012 and April 2020. Data regarding age, gender, initial presenting symptoms, tumor location, and radiological characteristics were collected. Treatment strategies and analyzed prognosis were documented. Survival curves were generated using the Kaplan-Meir method, and data were analyzed using SPSS (version 23.0, IBM Corp.).

RESULTS

The study cohort comprised 11 patients, including 10 males and 1 female. The age at diagnosis ranged from 4 to 15 years, with a median age of 10.6 years. Headache was the most common presenting symptom, observed in 81.8% (9/11) of patients. Tumor locations in the supratentorial and infratentorial regions exhibited a similar occurrence rate. All tumors showed strong contrast enhancement on T1-weighted images. The average survival time for the 11 patients was 44.4 months. Among them, 5 patients died by the last follow-up visit, with a mean survival time of 8.8 months (one patient died in a car accident).

CONCLUSION

Headache is the predominant manifestation of PCNSL in pediatric patients. PCNSL demonstrates imaging characteristics resembling various intracranial tumors and is associated with a poor prognosis. Therefore, pediatric neurosurgeons should exercise caution in diagnosing and treating intracranial lymphoma.

Clinical pathology of primary central nervous system lymphoma in HIV-positive patients-a 41 Chinese patients retrospective study

OBJECTIVES

The purpose of this study was to investigate the clinicopathological characteristics of primary central nervous system lymphoma (PCNSL).

METHODS

We collected 41 PCNSL formalin-fixed, paraffin-embedded (FFPE) samples from human immunodeficiency virus (HIV)-positive patients and performed HE (haematoxylin-eosin) staining, immunohistochemistry (IHC) staining, in situ hybridization, fluorescence in situ hybridization (FISH). Real-time quantitative polymerase chain reaction (RT-qPCR) was performed in 9 cases of FFPE samples. Meanwhile, we analysed the clinical pathological significance of the results.

RESULTS

Seven patients had diffuse large B-cell lymphoma (DLBCL) with germinal centre B-cell (GCB)-like DLBCL, 32 had activated B-cell (ABC)-like DLBCL, and 2 had Burkitt lymphoma (BL). GCB-like DLBCL patients were older at onset (P = 0.040).A lower CD4⁺ T-cell count and a decrease in cerebrospinal fluid (CSF) glucose content were more frequent in ABC-like DLBCL (P = 0.012, P = 0.006). Overexpression of P53 was more in ABC-like DLBCL (P = 0.041). 73.2 % cases were Epstein-Barr encoding region (EBER) positive, which was more likely in ABC-like DLBCL patients (P = 0.037). EBV DNA were detected in 5/7 EBER-negative DLBCL cases and none (0/2) of the BL cases. All the cases were negative for HHV8 staining. None of the 7 Double expressor lymphoma (DEL) cases had BCL2, BCL6, or c-MYC genetic rearrangements.

CONCLUSIONS

HIV-related PCNSL showed unique clinical pathological significance. None of EBV detected in HIV-related BL and without HHV8 infectious are new sights in our single-center study of Chinese HIV-related PCNSL patients.

Glioblastoma and Other Primary Brain Malignancies in Adults: A Review

Importance

Malignant primary brain tumors cause more than 15 000 deaths per year in the United States. The annual incidence of primary malignant brain tumors is approximately 7 per 100 000 individuals and increases with age. Five-year survival is approximately 36%.

Observations

Approximately 49% of malignant brain tumors are glioblastomas, and 30% are diffusely infiltrating lower-grade gliomas. Other malignant brain tumors include primary central nervous system (CNS) lymphoma (7%) and malignant forms of ependymomas (3%) and meningiomas (2%). Symptoms of malignant brain tumors include headache (50%), seizures (20%-50%), neurocognitive impairment (30%-40%), and focal neurologic deficits (10%-40%). Magnetic resonance imaging before and after a gadolinium-based contrast agent is the preferred imaging modality for evaluating brain tumors. Diagnosis requires tumor biopsy with consideration of histopathological and molecular characteristics. Treatment varies by tumor type and often includes a combination of surgery, chemotherapy, and radiation. For patients with glioblastoma, the combination of temozolomide with radiotherapy improved survival when compared with radiotherapy alone (2-year survival, 27.2% vs 10.9%; 5-year survival, 9.8% vs 1.9%; hazard ratio [HR], 0.6 [95% CI, 0.5-0.7]; P < .001). In patients with anaplastic oligodendroglial tumors with 1p/19q codeletion, probable 20-year overall survival following radiotherapy without vs with the combination of procarbazine, lomustine, and vincristine was 13.6% vs 37.1% (80 patients; HR, 0.60 [95% CI, 0.35-1.03]; P = .06) in the EORTC 26951 trial and 14.9% vs 37% in the RTOG 9402 trial (125 patients; HR, 0.61 [95% CI, 0.40-0.94]; P = .02). Treatment of primary CNS lymphoma includes high-dose methotrexate-containing regimens, followed by consolidation therapy with myeloablative chemotherapy and autologous stem cell rescue, nonmyeloablative chemotherapy regimens, or whole brain radiation.

Conclusions and Relevance

The incidence of primary malignant brain tumors is approximately 7 per 100 000 individuals, and approximately 49% of primary malignant brain tumors are glioblastomas. Most patients die from progressive disease. First-line therapy for glioblastoma is surgery followed by radiation and the alkylating chemotherapeutic agent temozolomide.

European Association of Neuro-Oncology (EANO) guidelines for treatment of primary central nervous system lymphoma (PCNSL)

The management of primary central nervous system (PCNSL) is one of the most controversial topics in neuro-oncology because of the complexity of the disease and the limited number of controlled studies available. In 2021, given recent advances and the publication of practice-changing randomized trials, the European Association of Neuro-Oncology (EANO) created a multidisciplinary task force to update the previously published evidence-based guidelines for immunocompetent adult patients with PCNSL and added a section on immunosuppressed patients. The guideline provides consensus considerations and recommendations for the treatment of PCNSL, including intraocular manifestations and specific management of the elderly. The main changes from the previous guideline include strengthened evidence for the consolidation with ASCT in first-line treatment, prospectively assessed chemotherapy combinations for both young and elderly patients, clarification of the role of rituximab even though the data remain inconclusive, of the role of new agents, and the incorporation of immunosuppressed patients and primary ocular lymphoma. The guideline should aid the clinicians in everyday practice and decision making and serve as a basis for future research in the field.

Treatment Options for Recurrent Primary CNS Lymphoma

OPINION STATEMENT

Primary CNS lymphoma (PCNSL) constitutes a rare extranodal variant of non-Hodgkin lymphoma (NHL) with an annual incidence of 0.45/100,000. Given the paucity of large prospective clinical trials, there is no consensus treatment for refractory or relapsed (r/r) PCNSL, and available strategies are largely based on retrospective analyses. Patient age, performance status, previously administered treatment, duration of response, and molecular characteristics guide selection of salvage therapy. Patients with a good performance status (KPS >70), particularly ≤65 years, and adequate organ function should be considered for salvage polychemotherapy. Based on its high overall response rate even in the relapsed setting, we choose high-dose (≥ 3.5g/m²) methotrexate (HD-MTX) based regimens, e.g., R-MPV (rituximab, HD-MTX, procarbazine, and vincristine), for remission re-induction as long as patients were sensitive to first line HD-MTX-based regimens, especially when duration of previous response was ≥ 1 year. Following successful remission induction, we choose myeloablative chemotherapy (e.g., thiotepa, busulfan, cyclophosphamide) and subsequent autologous stem cell transplant in curative intent whenever feasible. Alternatively, conventional chemotherapy regimens (for example, monthly HD-MTX) or low-dose whole-brain radiation therapy (WBRT) are selected for consolidation in non-transplant candidates in complete remission. In cases of HD-MTX refractory disease or contraindications, we use pemetrexed; temozolomide/rituximab; high-dose cytarabine; or whole brain radiation for remission induction. Clinical trial participation is considered as well. Emerging therapies for upfront or salvage therapy under ongoing investigation include bruton tyrosine kinase inhibition (e.g., ibrutinib), immunomodulatory drugs (e.g., lenalidomide), immune checkpoint inhibitors (ICI, e.g., nivolumab), and chimeric antigen receptor T (CAR-T) cell therapy.

Socioeconomic deprivation and survival outcomes in primary central nervous system lymphomas

Objective

To our knowledge, the impact of area-level socioeconomic status (SES) has not yet been described in primary central nervous system lymphomas (PCNSLs). Current study sought to explore the association of socioeconomic deprivation, measured using the Area Deprivation Index (ADI), with PCNSL outcomes.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify PCNSL patients diagnosed between 2006 and 2015 for our analyses. The impact of ADI on overall survival (OS) and cancer-specific survival (CSS) were investigated. Survival analyses were conducted using Kaplan-Meier method with log-rank tests. The Inverse Probability Weighting (IPW) analysis and multivariate cox proportional hazards regression analysis were employed to make covariate adjustments. Multiple mediation analysis (MMA) was performed to estimate the mediating effects.

Results

A total of 3159 PCNSL patients classified into low and high ADI subgroups according to the median ADI score were studied. The Kaplan-Meier analyses showed that low ADI was significantly associated with higher OS rates (HR 1.15, 95%CI 1.06-1.26, P<0.01) and CSS rates (HR 1.15, 95%CI 1.05-1.27, P<0.01). Similar results were observed in analyses adjusted via IPW and multivariate cox methods. Subgroup analyses revealed that ADI could remain a prognostic indictor among different subsets. MMA revealed that several factors including chemotherapy and HIV status making up about 40% of the overall effect, mediated PCNSL survival disparities related to the ADI. Finally, multivariable logistic regression analysis showed that ADI as well as several other factors were independently related to receipt of chemotherapy.

Conclusions

Our study highlights the role of area-level SES in prognosis of PCNSLs. And several factors including chemotherapy and HIV status of PCNSL patents contributed to the CSS disparities between ADI subgroups were uncovered by MMA. Such relationships would highlight the importance of policies development to enhance healthcare delivery and promote awareness of HIV prevention and treatment in low-resource neighborhoods.

Different facets of intracranial central nervous system lymphoma and its imaging mimics

Lymphomas of the central nervous system (CNS) are broadly classified into primary CNS lymphoma (PCNSL) and secondary CNS lymphoma (SCNSL). PCNSL refers to lymphoma restricted to the brain, leptomeninges, spinal cord, or eyes without evidence of it outside the CNS at primary diagnosis, while SCNSL refers to secondary CNS involvement by systemic lymphoma. The brain is the most common site of involvement and intracranial CNS lymphoma has a highly variable imaging appearance and varies according to the patient’s clinical profile and immunity. This pictorial essay aims to illustrate the different facets of intracranial CNS lymphomas on neuroimaging. This enables radiologists to be familiarized with their key diagnostic features and differentiate from their differential diagnoses, leading to early diagnosis, and treatment.

Clinical and Therapeutic Implications of Epstein-Barr Virus in HIV-Related Lymphomas

The incidence of lymphomas is increased in people living with HIV (PLWH). Aggressive B-cell non-Hodgkin lymphomas (NHLs) are the most common and are considered an AIDS-defining cancer (ADC). Although Hodgkin lymphoma (HL) is not considered an ADC, its incidence is also increased in PLWH. Among all HIV-related lymphomas (HRL), the prevalence of Epstein-Barr virus (EBV) is high. It has been shown that EBV is involved in different lymphomagenic mechanisms mediated by some of its proteins, contributing to the development of different lymphoma subtypes. Additionally, cooperation between both HIV and EBV can lead to the proliferation of aberrant B-cells, thereby being an additional lymphomagenic mechanism in EBV-associated HRL. Despite the close relationship between EBV and HRL, the impact of EBV on clinical aspects has not been extensively studied. These lymphomas are treated with the same therapeutic regimens as the general population in combination with cART. Nevertheless, new therapeutic strategies targeting EBV are promising for these lymphomas. In this article, the different types of HRL are extensively reviewed, focusing on the influence of EBV on the epidemiology, pathogenesis, clinical presentation, and pathological characteristics of each lymphoma subtype. Moreover, novel therapies targeting EBV and future strategies to treat HRL harboring EBV are discussed.

CAR T-Cells for CNS Lymphoma: Driving into New Terrain?

Primary CNS lymphomas (PCNSL) represent a group of extranodal non-Hodgkin lymphomas and secondary CNS lymphomas refer to secondary involvement of the neuroaxis by systemic disease. CNS lymphomas are associated with limited prognosis even after aggressive multimodal therapy. Chimeric antigen receptor (CAR) T-cells have proven as a promising therapeutic avenue in hematological B-cell malignancies including diffuse large B-cell lymphoma, B-cell acute lymphoblastic leukemia, and mantle-cell lymphoma. CARs endow an autologous T-cell population with MHC-unrestricted effectivity against tumor target antigens such as the pan B-cell marker CD19. In PCNSL, compelling and long-lasting anti-tumor effects of such therapy have been shown in murine immunocompromised models. In clinical studies on CAR T-cells for CNS lymphoma, only limited data are available and often include both patients with PCNSL but also patients with secondary CNS lymphoma. Several clinical trials on CAR T-cell therapy for primary and secondary CNS lymphoma are currently ongoing. Extrapolated from the available preliminary data, an overall acceptable safety profile with considerable anti-tumor effects might be expected. Whether these beneficial anti-tumor effects are as long-lasting as in animal models is currently in doubt; and the immunosuppressive tumor microenvironment of the brain may be among the most pivotal factors limiting efficacy of CAR T-cell therapy in CNS lymphoma. Based on an increasing understanding of CAR T-cell interactions with the tumor cells as well as the cerebral tissue, modifications of CAR design or the combination of CAR T-cell therapy with other therapeutic approaches may aid to release the full therapeutic efficiency of CAR T-cells. CAR T-cells may therefore emerge as a novel treatment strategy in primary and secondary CNS lymphoma.

Treatment of lymphomas via regulating the Signal transduction pathways by natural therapeutic approaches: A review

Lymphoma is a heterogeneous group of malignancies, which comprises 4.2 % of all new cancer cases and 3.3 % of all cancer deaths in 2019, globally. The dysregulation of immune system, certain bacterial or viral infections, autoimmune diseases, and immune suppression are associated with a high risk of lymphoma. Although several conventional strategies have improved during the past few decades, but their detrimental impacts remain an obstacle to be resolved. However, natural compounds are considered a good option in the treatment of lymphomas because of their easy accessibility, specific mode of action, high biodegradability, and cost-effectiveness. Vegetables, fruits, and beverages are the primary sources of natural active compounds. The present review investigated the activities of different natural medicinal compounds including curcumin, MK615, resveratrol, bromelain, EGCG, and Annonaceous acetogenins to treat lymphomas. Moreover, in vitro and in vivo studies, classification, risk factors, and diagnosis of lymphoma are also discussed in the present review. The accumulated data proposed that natural compounds regulate the signaling pathways at the level of cell proliferation, apoptosis, and cell cycle to exhibit anti-lymphoma activities both in-vivo and in-vitro studies and suggested that these active compounds could be a good therapeutic option in the treatment of different types of lymphomas.

Gamma knife stereotactic radiosurgery as an effective tool in primary CNS lymphoma: Evaluation of stereotactic radiosurgery and methotrexate treatment in a prospective and observational clinical research study

OBJECTIVE

The purpose of this study was to compare the progression of Primary Central Nervous System Lymphoma (PCNSL) in patients treated with methotrexate (MTX) versus those treated with a combination of Stereotactic Radiosurgery (SRS) and MTX. Progression was measured via brain lesion count and tumor volume.

METHODS

This observational and prospective cohort study evaluated the outcome of SRS treatment of PCNSL in one hundred twenty-eight subjects. We analyzed baseline, prospective, and retrospective data of patients enrolled in the brain tumor registry between June 2010 and August 2017. Seventy-three patients were treated exclusively with MTX while the remaining fifty-five patients received a combination of SRS and MTX. Strict inclusion and exclusion criteria were established.

RESULTS

Mean survival rate for patients receiving combined SRS and MTX treatment was significantly higher (52.6 months) compared to the MTX group (19.8 months); p = 0.0029. At the 36 months follow-up, patients treated with SRS and MTX also had a lower rate of tumor progression (32.7 %) than the MTX group (95.9 %); p = 0.00192. Local tumor control was achieved in all patients treated with SRS. No clinical toxicity was observed in this group.

CONCLUSIONS

Clinical results obtained from this observational study highlight the potential effectiveness of SRS in the treatment of PCNSL. Although treatment outcomes have improved in the past years, additional evidence in the clinical design of randomized trials is needed to evaluate the strength of this treatment in specific situations.

The clinical heterogeneity of entirely nonenhancing CNS lymphoma: a case series

CNS lymphoma often presents with atypical imaging characteristics leading to delay in diagnosis and initiation of treatment. Among the most rarely reported of these is entirely nonenhancing CNS lymphoma, which is estimated at an incidence of about 1%. Here, we present three cases of nonenhancing CNS lymphoma in immune competent patients at both initial presentation and recurrence and in primary as well as secondary CNS lymphoma. Diffusion- and perfusion-weighted imaging was found helpful in diagnosis in some cases.

HIV prevalence in primary central nervous system lymphoma: A systematic review and meta-analysis

HIV infection is considered a major risk factor for primary central nervous system lymphoma (PCNSL). However, the percentage of PCNSL that occurs in HIV + patients is not well defined. We aimed to assess the prevalence of HIV infection in patients with PCNSL through a systematic review and meta-analysis. Electronic databases were searched for studies assessing the presence of HIV infection in series of patients with PCNSL. Pooled prevalence of HIV infection in PCNSL was calculated, with a subgroup analysis based on the geographic area. Twenty-seven studies with 6422 patients were included. Overall, pooled prevalence of HIV infection among PCNSL patients was 6.1 % with high heterogeneity. In the subgroup analysis, pooled prevalence was 3.6 % in India with low heterogeneity, 30.2 % (overall) and 16.5 % (after 2000) in the USA with high heterogeneity, 5.7 % in Europe with high heterogeneity, 2.2 % in East Asia with null heterogeneity, 7.3 % in South America with moderate heterogeneity. In conclusion, only a minor part of PCNSL occurs in patients with HIV. The results stratified by geographic area reflect the different prevalence of HIV infection in the general population, except for India, probably due to the shorter life expectancy of HIV + patients.

Autoimmune disease-related primary CNS lymphoma: systematic review and meta-analysis

BACKGROUND

Recent studies suggest a relatively high prevalence of autoimmune disorders (AD) among primary CNS lymphoma (PCNSL) patients, however, the literature is limited to case reports. To gain a better understanding of AD-PCNSL we reviewed and analyzed all cases described in the literature.

METHODS

We searched the MEDLINE database using the search terms 'central nervous system lymphoma' or 'CNS lymphoma' along with AD-related terms. We selected 39 records for qualitative synthesis of data and identified 50 AD-PCNSL. Clinical, imaging and outcome data were collected. Overall survival (OS) was analyzed with the Kaplan-Meier method. Univariate and multivariate analyses were performed using log rank test and Cox proportional hazard model.

RESULTS

Most common AD were systemic lupus erythematosus (24%), multiple sclerosis (16%), and myasthenia gravis (14%). All patients had received immunosuppressants for their AD. Median interval from AD until PCNSL diagnosis was 108 months (range: 11-420). Male-to-female ratio was 0.42 and AD-PCNSL was diagnosed at a median age of 57 years (range: 2-88). On imaging lesions typically localized to the hemispheres (65%) and displayed peripheral enhancement (74%). Pathological evaluation revealed diffuse large-B-cell lymphoma (DLBCL) subtype (80%) and Epstein-Barr virus positivity (75%) in most AD-PCNSL. Median OS was 31 months. Age > 60 years (p = 0.014) was identified as a significant prognostic factor.

CONCLUSIONS

AD requiring immunosuppression appear over-represented in the population of PCNSL patients. Aggressive polychemotherapy can accomplish long term OS in AD-PCNSL comparable to immunocompetent patients. Age > 60 may serve as a prognostic factor.

Primary dural lymphomas: Clinical presentation, management, and outcome

BACKGROUND

Clinical experience is limited for primary central nervous system (CNS) lymphoma that arises from the dura mater, which is denoted with the term primary dural lymphoma (PDL). This study was aimed at determining the relative incidence, presentation, and outcomes of PDL.

METHODS

The institutional databases of the Divisions of Neuro-Oncology at the Massachusetts General Hospital and the Yale School of Medicine were retrospectively searched for patients with primary CNS lymphoma. Patients with pathologically confirmed dural lymphoma and no evidence of primary cerebral or systemic involvement were identified. Clinical data, diagnostic findings, treatments, and outcomes were recorded.

RESULTS

A total of 20 patients with PDL were identified, and they represented 6.3% of the individuals with primary CNS lymphomas (20 of 316). Histopathological examination of PDL revealed the following underlying subtypes: diffuse large B-cell lymphoma (10 of 20 patients), marginal zone lymphoma (6 of 20), follicular lymphoma (2 of 20), undefined B-cell non-Hodgkin lymphoma (1 of 20), and T-cell non-Hodgkin lymphoma (1 of 20). On imaging, all tumors appeared as extra-axial masses with avid contrast enhancement and mostly mimicked meningioma. The median apparent diffusion coefficient value was 667 ± 26 mm² /s. Cerebrospinal fluid analyses and symptoms were nonspecific, and the diagnosis rested on tissue analysis. Therapeutic approaches included surgery, radiotherapy, and chemotherapy. The median overall survival was not reached after 5 years. Three patients were deceased at database closure because of tumor progression. The extent of tumor resection correlated positively with overall survival (P = .044).

CONCLUSIONS

PDL is a rare variant of primary CNS lymphoma that can be radiographically mistaken for meningioma. The outcome is excellent with multimodality treatment, and aggressive surgery may convey a survival advantage in select cases.

CNS Infections in Immunoincompetent Patients : Neuroradiological and Clinical Features

In patients with immunodeficiency the pathogen spectrum of central nervous system (CNS) infections is broader and different from that of immunocompetent patients. Numerous opportunistic infections are characterized by a high prevalence of viral, bacterial and parasitic pathogens, and depend on the type of impaired immune defense, for example impaired T‑cell or monocyte function, monoclonal antibody treatment, and impaired granulocyte function. Neuroradiological features as well as laboratory findings are often different and versatile in comparison to immunocompetent individuals and pathognomonic imaging findings do not exist; however, knowledge of possible pathways of pathogens in the CNS and preferred tissue affection may help in narrowing down differential diagnoses. Therefore, knowledge of the type of patient and the performed immunomodulatory therapy is essential for the neuroradiological assessment and the differential diagnostic considerations. Moreover, parenchymal reactions in the sense of an immune reconstitution inflammatory syndrome (IRIS) can occur when immunocompetence is restored. This review focus on the most common pathologies in immunocompromised patients, and an overview of imaging features but also of pathology and clinical aspects is given. The synopsis of anamnestic information, clinical findings and structured analysis of the lesion pattern, its spread and short-term follow-up may increase the correct diagnostic classification; however, the gold standard is still determination of the pathogen in the cerebrospinal fluid (CSF), blood cultures or biopsies.