Low-Dose and Limited-Volume Radiotherapy Alone for Primary Dural Marginal Zone Lymphoma: Treatment Approach and Review of Published Data

Primary central nervous system marginal zone lymphoma

Marginal zone lymphoma (MZL) is the most common indolent lymphoma primarily arising in the central nervous system (CNS). To date, 207 cases of primary CNS MZL (PCNSMZL) were published, mostly as single case reports or small case series. It most commonly presents as extra-axial dural-based masses, more frequently in middle-aged women, displaying an insidious onset, with a long history of symptoms preceding the diagnosis. PCNSMZL can be radiographically mistaken for meningioma. PCNSMZL consists of CD20+ , CD3- small B lymphocytes with varying degrees of plasmacytic differentiation and low proliferation index. Trisomy 3, but not MALT1 or IgH translocation, is a common genetic abnormality. Other recurrent genetic abnormalities involve TNFAIP3 and NOTCH2. Ethiopathogenesis was poorly investigated. Due to its rarity, standard of care remains to be defined; it exhibits an excellent prognosis after varied treatments, such as surgery, radiotherapy, chemotherapy or their combinations. Nevertheless, each treatment should be considered after an accurate analysis of overtreatment risk. Short follow-up is a major limitation in reported PCNSMZL cases, which restrains our knowledge on long-term results and iatrogenic sequels. This review was focussed on presentation, differential diagnoses, pathological findings, treatment options and clinical outcomes of PCNSMZL; recommendations for best clinical practice are provided.

Intracranial dural based marginal zone MALT-type B-cell lymphoma: a case - Based update and literature review

OBJECTIVES

Dural based Marginal Zone MALT-type B-Cell Lymphoma (MZBCL) is an intracranial tumor that can mimicking meningioma both from a clinical and a radiological point of view. A standard treatment protocol is still lacking. Aim of the present work is to provide an update of the present literature regarding this rare neoplasia.

PATIENTS AND METHODS

We report the case of a patient with a dural-based lesion mimicking a meningioma of the tentorium. After surgical treatment, the diagnosis was of MZBCL. A literature review is performed to highlight the typical characteristics of this rare intracranial lesion and to define the best therapeutic approach.

RESULTS

Literature review included 38 articles describing 126 cases of intracranial dural-based MZBCL. No clinical trial has been found. Clinical and histopathological features are properly collected to provide a guide for future cases. Different treatment options have been attempted. Combination of surgery with adjuvant radiation therapy is the most used option.

CONCLUSIONS

MZBCL should be considered in differential diagnosis for dural-based intracranial lesion. Surgery followed by radiation therapy is the most reported treatment. As a consequence of the rarity of this disease, of its indolent progression and of the lack of adequate follow-up, it is not possible to define it is the best treatment option.

Primary Dural Non-Hodgkin's Lymphoma as a Diagnostic Pitfall: Report of a Rare Presentation with Review of Literature

Primary central nervous system lymphomas (PCNSLs) account for 2%-3% of all primary brain tumors. Lymphomas arising from the dura, without brain and other systemic involvement, constitute a tiny fraction of this rare group. Most dural lymphomas present as dural-based masses and an acute presentation as a subdural hematoma is exceptional, with only five such cases reported previously in the literature. We present the case of a 65-year-old female who was admitted with complaints of slurring of speech, visual disturbances, and reduced appetite for 2 days. Computerized tomography scan showed a crescentic hyperdense area in the left fronto-temporo-parietal region with no bony or extracranial involvement suggestive of acute subdural hematoma. There was a history of a similar episode 3 months back, wherein she was operated upon and followed up conservatively. Craniotomy for drainage was performed, and histopathology revealed a non-Hodgkin's Lymphoma. Primary lymphoma of the dura is a rare subtype of PCNSL. This case is being reported for its unusual presentation as a common entity-an acute subdural hematoma.

Primary Dural Mucosa-associated Lymphoid Tissue Lymphoma Mimicking Falx Meningioma: A Case Report

An 85-year-old woman presented with ataxia and deterioration of cognitive functions. She had no history of autoimmune diseases or viral infections. Magnetic resonance imaging showed a solitary mass lesion at the cerebral falx on contrast-enhanced T1-weighted imaging. Gross total resection of the lesion involving the dura mater was performed by bifrontal craniotomy. Histological examination showed diffuse infiltration of small lymphocytes and plasma cells. There was also some proliferation of large lymphocytes with folded nuclei, high-density chromatin, and inconspicuous nucleoli. The large atypical B lymphocytes did not demonstrate diffuse dense sheet findings. Meningothelial components were not detected. Immunohistochemistry was positive for pan B-cell antigens. The analysis of the kappa/lambda ratio indicated kappa immunoglobulin light chain-restricted B-cell proliferation. The final histopathological diagnosis was mucosa-associated lymphoid tissue lymphoma. Systemic screening examinations were then performed. Histological findings of the bone marrow showed normal findings without atypical lymphocytes. A chromosomal study of the bone marrow showed 46, XX. 18F fluoro-2-deoxyglucose positron emission tomography showed high accumulations at the left pterygoid muscle and the right transverse processes of the thoracic vertebrae, and mild accumulation at the right ilium bone, which indicated disseminated lesions. One year later, thickening of the dura mater was detected. Therefore, gamma knife surgery was performed. Two years later, she was alive without neurological deterioration, and magnetic resonance imaging showed no evidence of recurrence.

Chemotherapy is an efficient treatment in primary CNS MALT lymphoma

BACKGROUND

Mucosae-associated lymphoid tissue (MALT) lymphomas are a rare and poorly understood form of primary central nervous system lymphoma (PCNSL). The aim of this study was to better describe these tumors, their management and their long-term prognosis.

METHODS

Patients with primary CNS MALT lymphoma (PCNSML) were retrospectively selected from the database on PCNSL of the Pitié-Salpêtrière Hospital.

RESULTS

Of 662 PCNSL, 11 (1.7%) PCNSML (9 females and 2 males, median age: 56 years) were selected. The median time from first symptoms to diagnosis was 13 months. Location was dural in 8 cases and parenchymal in 3 cases. The disease was multifocal/diffuse in 7 cases. In first line, all patients received chemotherapy (high-dose methotrexate (HD-MTX) based chemotherapy (n = 4) and non-HD-MTX-based chemotherapy (n = 7)), preceded by surgery in 4 cases. None received radiotherapy. According to the IPCG (International PCNSL Collaborative Group) criteria, the overall response rate was 7/11 (64%). At latest news, 5 patients had persistent contrast enhancement, stable with no treatment since a median of 57 months, raising the question of complete response despite persisting contrast enhancement. No patient developed neurotoxicity except for one patient who subsequently received radiotherapy. The median follow-up was 109 months. The median progression-free survival was 78.0 months and the 10-year overall survival rate was 90%.

CONCLUSION

This is the largest series demonstrating that chemotherapy is an efficient treatment in PCNSML, with an excellent long-term outcome and the absence of neurotoxicity, and calling into question the relevance of the IPCG criteria for the evaluation of response.

A Case of Solitary Laryngotracheal Lymphoma Evaluated by 18F-FDG PET/CT

ABSTRACT

Solitary non-Hodgkin lymphoma of the trachea is extremely rare. Herein, we reported a case of solitary laryngotracheal lymphoma in a 55-year-old man. He complained of cough, tachypnea, and dyspnea. 18F-FDG PET/CT showed a hypermetabolic lesion in the subglottic larynx and upper cervical trachea. The subsequent histology and immunohistochemistry of the laryngotracheal lesion tissue confirmed the diagnosis of non-Hodgkin lymphoma (mucosa-associated lymphatic tissue lymphoma).

Local Control of Primary Dural Central Nervous System Lymphoma Achieved With Radiotherapy

Primary central nervous system lymphomas (PCNSL) are extranodal non-Hodgkin's lymphomas (NHL) confined to the brain, leptomeninges, eyes, or spinal cord. Primary leptomeningeal lymphoma (PLML), without parenchymal involvement, synchronous cerebrospinal, or systemic disease is rare. The estimated incidence of PLML is 7% of all PCNSL, which in turn accounts for about 2% of all primary brain tumors and 0.8% of all lymphomas.

The incidence of PCNSL in Western countries is approximately five cases per million inhabitants per year, and less than 5% of all primary tumors of the central nervous system (CNS), although it is worth mentioning that the incidence seems to be increasing. The largest series of cases reported in the medical literature collect information from no more than nine patients; in these series, the median age at diagnosis is 57 years; in general, all patients present with cerebrospinal fluid alteration, and the median overall survival rate is close to eight months.

With our case series, we aim at sharing the experience of four patients diagnosed and treated at the National Cancer Institute between 2010 and 2020, establishing a correlation of the clinical, imaging, and histopathological presentation, the response to treatment based on radiotherapy and chemotherapy, and the clinical outcomes reported in the medical records.

Whole brain radiation therapy for primary central nervous system marginal zone lymphoma: a case report

A standard radiation therapy protocol for primary central nervous system marginal zone lymphoma (CNS-MZL) has not been established. The International Lymphoma Radiation Oncology Group suggested a radiation therapy dose of 30-36 Gy for lesions of well-defined CNS-MZL. We report a case of relatively low-dose whole brain radiation therapy (WBRT) for ill-defined CNS-MZL. A 56-year-old man who presented with sudden left-sided convulsions and impaired consciousness was diagnosed with CNS-MZL. The tumor had an ill-defined lesion, without cerebrospinal fluid involvement. WBRT, consisting of 25.2 Gy in 14 fractions, was administered owing to the difficulty in target delineation for focal radiation therapy. No chemotherapy was administered during the treatment course. After the 36-month follow-up period, the patient maintained complete remission without neurological disorders. This report describes the usefulness of relatively low-dose WBRT for ill-defined CNS-MZL.

A Rare Case of Composite Dural Extranodal Marginal Zone Lymphoma and Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma

Background

Primary extranodal marginal zone lymphoma (MZL) of the dura is a rare neoplastic entity in the central nervous system (CNS).

Methods

We used literature searches to identify previously reported cases of primary dural MZL. We also reviewed clinical, pathologic, and radiographic data of an adult patient with concurrent dural MZL and chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL).

Results

We identified 104 cases of dural MZL in the literature. None of them presented concurrently with another type of non-Hodgkin lymphoma. This is the first report of composite lymphoma consisting of dural MZL and CLL/SLL in the bone marrow and lymph nodes.

Conclusion

Primary dural MZL is a rare, indolent low-grade CNS lymphoma, with a relatively good prognosis. Its treatment is multidisciplinary and often requires surgical intervention due to brain compression, along with low to moderate doses of radiotherapy and/or systemic chemotherapy.

Primary spinal mucosa-associated lymphoid tissue lymphoma: A case report

RATIONALE

Mucosa-associated lymphoid tissue (MALT) lymphoma is an indolent B-cell lymphoma which occurs mainly in the organs having mucosal layer and owns a fairly good prognosis. To date, 7 cases of spinal primary MALT has been reported before. However, there is no consensus on the optimal adjuvant treatment modalities for primary spinal MALT. The aim of this study was to add a new case of MALT which responded well to systemic therapy to the literature and to review the current literature.

PATIENT CONCERNS

A 68-year-old woman visited to our hospital due to back pain and progressive bilateral lower extremity weakness for 2 months. Magnetic resonance imaging (MRI) of the spine revealed a diffusely contrast-enhancing epidural mass extending from vertebral body T6 to T8 with compression of the spinal cord. Due to the spinal cord compression, patient underwent surgical resection. Histological examination indicated monocytoid small B-cells. Immunochemical study demonstrates that most tumor cells were positive for CD20, CD21, CD45, CD79a, CD43, bcl-2 with Ki-67 labing index was 15%, but were negative for CD3, CD5 cyclin D1, BCL6, and CD23. The positron emission tomography/computer tomography (PET/CT) revealed that right iliac wing and right liver were metastases for the standard uptake value (SUV) were 9.05 and 8.35, respectively.

DIAGNOSES

Based on these findings, final diagnosis of spinal MALT lymphoma was made.

INTERVENTIONS

After the diagnosis, the patient received 6 cycles of immuno-chemotherapy and repeated intrathecal methotrexate and intrathecal cytarabine.

OUTCOMES

At 1 year follow up, no recurrence or other dissemination was detected.

LESSONS

Chemotherapy and/or radiation have been employed in larger case series. While there is no defined treatment guideline for this rare disease entity, our reported case suggests a favorable prognosis when combining both surgical and adjuvant systemic approach.

Marginal zone dural lymphoma: the Memorial Sloan Kettering Cancer Center and University of Miami experiences

Dural lymphoma (DL) is a rare type of primary CNS lymphoma arising from the dura mater. The optimal treatment is uncertain. A retrospective review was performed on 26 DL patients. Seventeen patients underwent resection and nine had a biopsy. Twenty three patients could be assessed for a response to treatment after surgery. Thirteen received focal radiotherapy (RT), six whole brain RT (WBRT), three chemotherapy alone and one chemotherapy followed by WBRT. Twenty two achieved complete response (CR) and one a partial response (PR). Four patients relapsed (two local and two systemic). Median follow up was 64 months, with median progression free survival (PFS) and OS not reached. Three year PFS was 89% (95% CI 0.64-0.97). All patients are alive at last follow-up, demonstrating that DL is an indolent tumor with long survival. CR is achievable with focal therapy in the majority of cases, but there is a risk for relapses and long-term follow-up is recommended.

Modern radiation therapy for extranodal lymphomas: field and dose guidelines from the International Lymphoma Radiation Oncology Group

Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT.

Management of the marginal zone lymphomas

Marginal zone lymphomas (MZL) represent around 8 % of all non-Hodgkin lymphomas. During the last decades a number of studies have addressed the mechanisms underlying the disease development. Extranodal MZL lymphoma usually arises in mucosal sites where lymphocytes are not normally present from a background of either autoimmune processes, such as Hashimoto thyroiditis or Sjögren syndrome or chronic infectious conditions. In the context of a persistent antigenic stimulation, successive genetic abnormalities can progressively hit a B-cell clone among the reactive B-cells of the chronic inflammatory tissue and give rise to a MALT lymphoma. The best evidence of an etiopathogenetic link is available for the association between Helicobacter pylori-positive gastritis and gastric MALT lymphoma. Indeed, a successful eradication of this micro-organism with antibiotics can be followed by gastric MALT lymphoma regression in more than 2/3 of cases. Other microbial agents have been implicated in the pathogenesis of MZL arising in the skin (Borrelia burgdorferi), in the ocular adnexa (Chlamydophila psittaci), and in the small intestine (Campylobacter jejuni). The prevalence of hepatitis C virus (HCV) has also been reported higher in MZL patients (particularly of the splenic type) than in the control population, suggesting a possible causative role of the virus. In non-gastric MALT lymphoma and in splenic MZL the role of the antimicrobial therapy is, however, less clear. This review summarizes the recent advances in Marginal Zone Lymphomas, addressing the critical points in their diagnosis, staging and clinical management.

The role of radiation therapy in the management of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is an aggressive neoplasm with a poor prognosis. Early studies of whole brain radiation therapy (WBRT) alone revealed a robust initial response but high rates of local recurrence with long-term follow-up. The addition of high-dose methotrexate (HDMTX)-based chemotherapy improved the durability of disease control. However, delayed neurotoxicity emerged as an important complication, mainly in elderly patients. Therefore, researchers have investigated eliminating WBRT or reducing its dose. Multiple studies of chemotherapy alone have demonstrated inferior disease control. On the other hand, a phase III trial reported that WBRT may be deferred until relapse without compromising survival; however, this trial is fraught with flaws. A recent study of immunochemotherapy and dose-reduced WBRT demonstrated excellent outcomes. Currently, this regimen is being studied in a multi-institutional trial by the Radiation Therapy Oncology Group. WBRT maintains an important position in the armamentarium against PCNSL. This article aims to describe its evolving role.

Primary spinal marginal zone lymphoma relapse at a different spinal level after remission of the primary lesion

Study Design Case report. Objective Most spinal lymphomas occur in the context of systematic lymphomas. Marginal zone lymphoma (MZL) is a type of B-cell lymphoma originating from the marginal zone of B-cell follicles. Mucosa-associated lymphoid tissue (MALT) lymphoma is a type of extranodal MZL and rarely occurs in the central nervous system. To date, there has been only one case report of primary spinal MALT lymphoma and there are no case reports of relapsed MALT lymphoma at a different location of the spine. Results A 58-year-old man complained of gait disturbance and urinary dysfunction. Magnetic resonance images showed an abnormal lesion in the epidural space at T11-L1 compressing the conus medullaris. The patient underwent laminectomy and partial resection of the tumor. Histopathologic and immunohistochemical findings were consistent with MALT lymphoma. Following postoperative radiotherapy, the epidural mass disappeared completely. Three years later, epidural MALT lymphoma at a different location in the thoracic spine (T8-T10) occurred and caused myelopathy again. Histologic diagnosis of the relapsed tumor was the same as had been seen 3 years previously. Conclusions This is the first case report of relapsed spinal MALT lymphoma at a different location of the thoracic spine. Though the prognosis of MALT lymphoma is fairly good, careful follow-up is needed to screen any relapse or transformation to a high-grade lymphoma.

Rare case of cerebral MALToma presenting with stroke-like symptoms and seizures

Mucosa-associated lymphoid tissue (MALT) cells are present in gastrointestinal mucosa but rarely found in the central nervous system (CNS). We describe an unusual and rare case of CNS MALT lymphoma in a patient presenting with stroke-like symptoms.

Primary dural lymphoma: a novel concept of heterogeneous disease

Spinal primary dural lymphoma (PDL) is uncommon with a total of 37 previous well-documented cases reported, including one diagnosed in the authors' institution. More recently we encountered an additional case of spinal PDL that, similarly to our previous case, was grade 1-2 follicular B-cell PDL. Our two cases were diagnosed over a 3-year interval in a 72-year-old female and a 74-year-old male, respectively. An exhaustive literature review on PDL was performed consequently to reveal that: (i) spinal and cerebral sites of involvement by PDL are constantly mutually exclusive; and (ii) unlike cerebral PDL, which is usually of marginal zone B-cell type, only two of the 38 cases of spinal PDL were diagnosed as such, diffuse large B-cell lymphoma being the most commonly encountered type in the spine. This divergence infers that, in contrast to the prevailing concept that PDL is a unique disease group, PDL appears to be rather heterogeneous with a difference in predilection of lymphoma type for the anatomical site of dural involvement. Such a site-specific lymphoma-type predilection phenomenon, well-recognized in other organ systems, has not been acknowledged in PDL. This report brings new insights into PDL, and may contribute to a better understanding of nervous system pathophysiology and lymphoma classification.

Primary CNS lymphoma other than DLBCL: a descriptive analysis of clinical features and treatment outcomes

Diffuse large B-cell lymphoma (DLBCL) constitutes most primary central nervous system (CNS) lymphoma (PCNSL), whereas T-cell, low-grade and Burkitt’s lymphomas (BL) are rarely encountered. Due to the paucity of cases, little is known about the clinical features and treatment outcomes of PCNSL other than DLBCL. The objective of this study was to describe the clinical characteristics and outcomes for patients with PCNSL other than DLBCL. Fifteen patients, newly diagnosed with PCNSLs other than DLBCL between 2000 and 2010, were included. The male to female ratio was 0.67:1 with a median age of diagnosis of 31 years (range 18–59). Pathologic distributions were as follows: peripheral T-cell lymphoma (PTCL; n = 7), marginal zone B-cell lymphoma (MZBCL; n = 1), lymphoplasmacytic lymphoma (LPL; n = 2), Burkitt’s lymphoma (n = 1), other unspecified (T-cell lineage, n = 2; B-cell lineage, n = 2). Thirteen patients (87%) showed Eastern Cooperative Oncology Group performance score (ECOG PS) 1–2. The remaining two were one PTCL patient and one Burkitt’s lymphoma patient. Of the nine patients with T-cell lymphoma, five (56%) had multifocal lesions, and one (20%) with LPL of the five patients with B-cell lymphoma showed a single lesion. Leptomeningeal lymphomatosis was identified in two patients (one with Burkitt’s lymphoma and one with unspecified B-cell lymphoma). Two patients (22%) with T-cell lymphoma died 7.7 and 23.3 months later, respectively, due to disease progression, despite HD-MTX-based therapy. Six patients with T-cell lymphoma (6/9, 66.7%) and four patients with low-grade B-cell lymphoma (4/5, 80%) achieved complete response and have survived without relapse (Table 3). One patient with Burkitt’s lymphoma showed poor clinical features with ECOG PS 3, deep structure, multifocal, and leptomeningeal lymphomatosis, and died 7.6 months after the initiation of treatment. In comparison with previously reported DLBCLs (median OS 6.4 years, 95% CI 3.7–9.1 years), T-cell lymphoma showed equivocal or favorable clinical outcomes and low-grade B-cell lymphomas, such as MZBCL and LPL, had a good prognosis. However, primary CNS Burkitt’s lymphoma presented poor clinical outcomes and showed a comparatively aggressive clinical course. In conclusion, primary CNS lymphoma other than DLBCL occurred more in younger patients and showed a generally good prognosis, except for Burkitt’s lymphoma. Further research on treatment strategies for Burkitt’s lymphoma is needed.

Dural MALT lymphoma with disseminated disease

Central nervous system (CNS) lymphoma involving the dura mater is very rare and histologically is usually a subtype of non-Hodgkin's lymphoma (NHL) termed mucosa-associated lymphoid tissue (MALT) lymphoma. We present a case of a 46-year old woman with dural MALT lymphoma that was found to also involve a lacrimal gland, inguinal lymph nodes, and bone marrow. Magnetic resonance imaging of the brain showed an extra-axial enhancing mass approximately 6 cm in maximum diameter along the right frontotemporal convexity. Histopathology of the resected dural mass showed MALT lymphoma expressing CD20, CD52, CD19, and CD38. Molecular studies of the B-cell receptor heavy chain demonstrated monoclonality at the involved sites. The patient was treated with four cycles of fludarabine, mitoxantrone, and rituximab with complete remission. She had recurrence in the subcutaneous tissue of the back at 12 months but has remained free of intracranial disease for 31 months. A review of the literature reveals 57 cases of dural MALT lymphoma. Only 4 had extra-CNS involvement at presentation, and only 3 had local recurrence of the dural tumor. Because of the indolent behavior of this tumor, the intracranial portion can be treated conservatively after resection with or without chemotherapy. Deferral of brain radiation can be considered with close clinical and neuroimaging follow up.

Primary central nervous system mucosa-associated lymphoid tissue lymphoma: case report and literature review

Primary presentation of intradural non-Hodgkin lymphoma is rare. Recently, B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) have been recognized as an important pathologic subtype. When MALT lymphomas present in the central nervous system (CNS), they are distinguishable from primary high-grade CNS lymphomas. We present the clinicopathologic features of 5 patients with primary CNS MALT lymphoma treated at our institution from 1999 to 2006. Four out of 5 patients were women, and all patients presented with headaches, focal motor deficits, or cranial nerve palsy. Radiologic studies demonstrated ill-defined dural masses in 3 and well-defined masses in 2 patients. Pathology revealed small to medium-sized cells with a moderate amount of cytoplasm and irregular nuclear borders, expressing pan B-cell markers (CD19, CD20, and CD79a) but lacking CD10, CD23, and cyclin D1, confirming low-grade MALT lymphoma. Plasma cells were encountered in all the biopsies with variable reactive T-cell infiltration. wedge chain restriction was seen in 3 patients. Therapy consisted of either surgical resection, whole-brain radiation, or systemic or intrathecal chemotherapy. There was no evidence of recurrence or systemic relapse in 4 patients at 4 years of follow-up. One patient died in 2 months, unrelated to CNS lymphoma. This case series illustrates the rare occurrence of low-grade dural B-cell lymphoma and the need to consider this entity in the differential diagnosis of CNS lesions.