Dural marginal zone lymphoma with massive amyloid deposition: rare low-grade primary central nervous system B-cell lymphoma. Case report

Primary cerebral immunoglobulin light chain amyloidoma in a patient with multiple sclerosis

A man in his 60s, known with multiple sclerosis, presented with seizures and paresis of the left arm and leg. Brain imaging showed a white matter lesion, right parietal, which was progressive over the last 6 years and not typical for multiple sclerosis. Brain biopsy showed a B-cell infiltrate with IgA lambda monotypic plasma cell differentiation and amyloid deposits, typed as lambda immunoglobulin light chain (AL). Bone marrow biopsy and PET/CT ruled out a systemic lymphoma. Extended history taking, blood and urine testing (including cardiac biomarkers) identified no evidence of systemic amyloidosis-induced organ dysfunction.Primary cerebral AL amyloidoma is a very rare entity where optimal treatment is difficult to assess. The patient was treated with locally applied volumetric modulated arc radiotherapy, 24 Gy, divided in 12 fractions. Afterwards, the paresis of the left arm partially resolved, and the function of the left leg improved. Seizures did not occur anymore.

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.

Mucosa‑associated lymphoid tissue in the central nervous system presenting as meningioma: A case report

Mucosa-associated lymphoid tissue (MALT) lymphoma involving meningeal tissue is rare condition, easily mistaken for meningiomas upon imaging. In this report, a case of primary left temporal lobe MALT lymphoma that was initially misdiagnosed as temporal meningioma is presented, with subsequent investigation into the mechanism and treatments. Clinically, MALT lymphomas can be easily confused with meningiomas based solely on imaging and clinical manifestations. MALT lymphomas are indolent, localized lesions that can be cured through surgical resection and radiotherapy. Currently, radiotherapy is the most commonly used treatment; however, the patient in the present report did not receive any chemotherapy or radiotherapy after surgery, and recent related examinations revealed a recurrence of lymphomas that had metastasized throughout the body. As a result, future patients may benefit from chemotherapy or radiotherapy, and clinicians should be more meticulous regarding patient follow-up.

Low‐grade B‐cell lymphoma of the central nervous system with plasmacytic differentiation and amyloid deposition

A 65-year-old woman with a resolved history of epilepsy due to a motor vehicle accident and hippocampal sclerosis presented with recurrent de novo seizures. Brain imaging demonstrated enhancement in the left parieto-occipital lobe. At histopathological examination, the lesion displayed a diffuse lymphoid infiltrate comprised of small atypical lymphocytes, plasmacytoid lymphocytes, and scattered plasma cells with amyloid deposition. Pathology workup demonstrated a monotypic B-cell phenotype of the lymphoid infiltrate, expressing lambda light chain restriction and plasmacytic differentiation without MYD88 mutations. The patient had no systemic evidence of lymphoma, plasma cell dyscrasia, or amyloidosis. A diagnosis of low-grade B-cell lymphoma of the central nervous system with plasmacytic differentiation and amyloid deposition was made.

Extranodal Marginal Zone Lymphoma of the Central Nervous System Includes Parenchymal-Based Cases With Characteristic Features

OBJECTIVES

To define the clinicopathologic features of extranodal marginal zone lymphoma (EMZL) of the central nervous system (CNS), including cases arising in CNS parenchyma, which have been reported only rarely.

METHODS

Twelve cases of CNS EMZL were identified, including 5 based in CNS parenchyma and 7 nonparenchymal cases arising in dura or choroid plexus.

RESULTS

Histologically, parenchymal cases were perivascular infiltrates without a dominant lymphoid mass, whereas nonparenchymal cases were masses of small lymphocytes. Plasma cells were a larger component of the infiltrate in parenchymal cases (median, 30%; range, 20%-50%) than nonparenchymal cases (median, 0%; range, 0%-5%; P < .001), and plasma cells were clonal by immunohistochemistry in 4 of 5 parenchymal vs 1 of 7 nonparenchymal cases (P = .07). Fluorescence in situ hybridization for MALT1 rearrangement was positive in 1 of 3 parenchymal and none of 3 nonparenchymal cases. Chromosomal microarray was abnormal in 5 of 7 cases (71%), with chromosome 6/6q alterations identified in 3 cases. No patients with parenchymal disease but all 6 (100%) with nonparenchymal disease achieved complete remission.

CONCLUSIONS

This case series, the first to include multiple parenchymal cases, clarifies the spectrum of clinical, pathologic, and genetic findings in CNS EMZL and suggests that parenchymal-based lesions may show less favorable prognosis than dural-based disease.

Primary Dural Lymphoma: Clinical Cases and Literature Review

Primary dural lymphoma (PDL) is an extranodal non-Hodgkin lymphoma that accounts for less than 1% of all central nervous system lymphomas. Primary dural lymphoma grows from the dura mater, and it is often diagnosed as meningioma or acute subdural hematoma due to its radiological characteristics. Surgery is the gold standard of therapy; in many patients, PDL is relatively benign with good outcome. Authors report their experience in three patients affected by extranodal non-Hodgkin lymphoma (PDL) mimicking a meningioma.

Cerebral Amyloidoma Resulting from Central Nervous System Lymphoplasmacytic Lymphoma: A Case Report and Literature Review

Cerebral amyloidomas are rare cerebral mass lesions often associated with significant morbidity. Cerebral amyloid accumulation can be the result of a number of disease states and it is crucial for proper patient care to identify the pathogenic process leading to amyloidoma formation. Low grade clonal B-cell processes are one cause of cerebral amyloidomas. We report a case of an 87-year-old woman who presented with a lymphoplasmacytic lymphoma associated cerebral amyloidoma complicated by cerebral hemorrhage, discuss the proper workup of this disease entity, and present a review of the literature on this topic.

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.

Giant solitary primary intracranial lymphoma masquerading as meningioma: a case and review of literature

Non-Hodgkin's lymphomas (NHL) with intracranial origin are very rare and constitutes about 1-2% of primary central nervous system lymphomas (PCNSL). Diffuse large B cell lymphoma (DLBCL) is the most common subtype of NHL and mostly seen in immunocompromised patients. Therefore, the occurrence of giant solitary DLBCL in an immunocompetent patient is puzzling. We present a case of 68-year-old man who was admitted at our facility with a history of “hypomnesia of two (2) months” duration. Magnetic resonance imaging (MRI) revealed a space occupying lesion in the bilateral frontal lobe and corpus callosum measuring about 5.4cm * 4.6cm * 3.8cm with mixed signal intensities and vasogenic edema around the mass. Radiological, this mass was mistaken for meningioma until histopathological studies revealed DLBCL. Giant solitary primary intracranial lymphomas are very rare and can be mistake for meningioma even with very experience radiologist or neurosurgeon since the radiological features of PCNSL can be very unspecific. We achieved to total resection because of the giant and solitary nature of our case. The prognosis of PCNSL is general very poor when the patient is immunocompromised. In immunocompetent patients, who are well managed with surgery and chemotherapy, the overall survival and quality of life can very encouraging.

Extranodal Marginal Zone Lymphoma of the Central Nervous System

Extranodal marginal zone lymphoma of the central nervous system (CNS EMZBL) is a rare disease. We present a review of the literature and describe its presentation, differential diagnosis, treatment options, and outcomes. Systematic search of PubMed, Medline, and Embase databases via the Ovid engine for primary articles and case reports yielded 37 unduplicated peer-reviewed articles of CNS EMZBL. We identified 69 cases in these articles and 1 unreported case at our institution, which were included for this review's analysis. Median age at diagnosis was 55 years (range, 18-78 years), with a female preponderance of 77% (n = 54). Most common presenting symptoms were headache in 43% (n = 30), seizures in 31% (n = 22), and visual defects in 27% (n = 19). The most common treatment modalities were localized therapies, which were provided to 67% (n = 47) of cases. These included radiotherapy in 27% (n = 19), radiotherapy with surgery in 24% (n = 17), and surgery alone in 16% (n = 11). Ninety percent (n = 63) of patients had a median follow-up of 23 months. Complete remission was experienced by 77% (n = 49) patients, and 22% (n = 14) were alive with disease. Three patients had evidence of relapse, and one patient died. CNS EMZBL is an indolent, low-grade, radiosensitive lymphoma with good treatment outcomes and prognosis. It is an important differential to consider in extra-axial dural-based masses. Individualized management plans, with preference given to localized treatment options, should be considered after factoring in the site and extent of disease, its resectability, and the expected adverse effects of systemic therapy.

Primary Meningeal Pleomorphic Xanthoastrocytoma With Anaplastic Features: A Report of 2 Cases, One With BRAF(V600E) Mutation and Clinical Response to the BRAF Inhibitor Dabrafenib

Primary meningeal gliomas are rare tumors composed of a heterogeneous group of neoplasms. We present 2 clinically aggressive cases of primary meningeal pleomorphic xanthoastrocytoma that clinically mimicked meningioma. One case presented in the posterior fossa of a 56-year-old woman; the other centered on the left operculum of a 35-year-old woman. These cases showed many of the classic features of pleomorphic xanthoastrocytoma, except that xanthomatous cells were rare and eosinophilic granular bodies were inconspicuous. Both cases exhibited high proliferative indices and superficially invaded the brain. One case harboring a BRAF mutation disseminated to the thecal sac and showed a clinical response to the targeted BRAF inhibitor dabrafenib. These cases seem to represent an unusual primarily extra-axial presentation of pleomorphic xanthoastrocytoma and may account for at least some of the previously reported cases of primary meningeal glioma and/or glial fibrillary acidic protein-immunoreactive meningioma variants. We suggest that BRAF mutation analysis be considered in all meningeal lesions showing atypical histologic or immunohistochemical profiles, particularly those exhibiting glial differentiation, as a diagnostic aid and possible indication for targeted therapy.

Extranodal Marginal Zone B-Cell Lymphoma of Mucosa-Associated Tissue Type Involving the Dura

Primary central nervous system marginal zone B-cell lymphoma (MZBCL) is very rare, with only a few reported cases worldwide. It has an indolent disease course with high cure potential. We experienced a rare case of dural MZBCL of mucosa-associated lymphoid tissue (MALT) in a 69-year-old man who presented with headache. A magnetic resonance imaging scan of brain showed a 1.9×3.6-cm-sized extra-axial mass with a broad based dural attachment to the anterosuperior aspect of the falx cerebri, radiographically consistent with meningioma. Surgical resection yielded a MZBCL of the MALT type. Histopathology revealed a lymphoplasmacytic infiltration of the dura, and immunohistochemical study showed a B-cell phenotype with CD20, bcl-2, MUM-1, Ki-67 positive. He was treated with chemotherapy after complete surgical resection and remained free of disease at 30 months after chemotherapy. MALT lymphoma must be considered in the differential diagnosis in patients presenting radiographically with meningioma.

Adnexal mass secondary to extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) with associated amyloid deposition

Systemic amyloid light chain amyloidosis (AL amyloidosis) is usually seen in association with a plasma cell disorder. Amyloid deposition associated with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is a rare phenomenon that is not typically associated with systemic AL amyloidosis. We describe the unusual case of a patient with an adnexal mass secondary to MALT lymphoma with associated amyloid deposition.

EBV-positive low-grade marginal zone lymphoma in the breast with massive amyloid deposition arising in a heart transplant patient: A report of an unusual case

According to the 2008 World Health Organization classification, low-grade lymphomas arising in transplant recipients are not considered as specific types of PTLD. Most such cases are not associated with EBV infections, although rare reports of post-transplant marginal zone lymphoma have been described. We describe the case of an 18-yr-old female with history of heart transplant who developed a breast mass, but was otherwise completely asymptomatic. Surgical excision of the mass and histopathologic examination showed a low-grade B-cell lymphoma most consistent with marginal zone lymphoma with massive amyloid deposition; furthermore, numerous tumor cells were positive for EBV by in situ hybridization for EBV-encoded RNA. The patient was treated with reduction in immunosuppression, and no additional lesions developed. This case describes an atypical presentation of post-transplant low-grade B-cell lymphoma, unusual in its location, histopathologic features, and association with EBV, thereby adding to the rare previous accounts of such an entity, suggesting the need to include post-transplant marginal zone lymphomas in the current classification of PTLD, and helping in determining the optimal treatment modalities for such tumors.

Primary spinal marginal zone lymphoma: case report and review of the literature

BACKGROUND AND IMPORTANCE

Marginal zone lymphoma (MZL) describes a heterogeneous group of indolent B-cell lymphomas. The World Health Organization recognizes 3 types of MZLs: splenic MZL, nodal MZL, and extranodal MZL of mucosa-associated lymphoid tissue. There is no consensus on the optimal adjuvant treatment modalities for intracranial primary MZLs. To date, no case of spinal primary MZL has been reported.

CLINICAL PRESENTATION

We present the first case of spinal MZL diagnosed in a 65-year-old man with progressive paraparesis. He underwent surgical removal of the main spinal tumor mass, which extended epidurally from vertebral body T3 to T7. Surgery was followed by 10 sessions of local irradiation for a total dose of 31 Gy. On long-term follow-up in 2010, the patient was in good health without any signs of residual or recurrent disease. Twenty-seven publications reporting on 61 cases of intracranial primary MZL were identified and reviewed. In the majority of cases of marginal zone B-cell lymphoma, adjuvant radiotherapy was used, with some combining radiotherapy and chemotherapy after surgical removal of the bulk of the main tumor. Long-term follow-up in most patients showed no evidence of disease and clinical well-being years after the initial diagnosis.

CONCLUSION

Chemotherapy and/or radiation have been used in larger case series. Although there is no defined treatment guideline for this rare disease entity, our review of the literature suggests a favorable prognosis when combining surgical and adjuvant radiotherapy approaches.

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue with amyloid deposition: a clinicopathologic case series

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a mature B-cell neoplasm that typically follows an indolent clinical course. Amyloid deposition associated with MALT lymphoma is uncommon. We describe the clinical and pathologic features of 20 cases of MALT lymphoma and associated amyloid deposition across diverse primary sites. Frozen section immunofluorescence performed on 4 cases suggests that these deposits are a localized form of AL amyloid. Clinical follow-up was available for 15 patients. Amyloid deposits distant from the initial site occurred in 5 cases, always at sites also involved by the underlying lymphoma. No definitive evidence of systemic amyloidosis affecting the heart, kidneys, or liver was present in any patient. Given the generally indolent clinical behavior of MALT lymphomas with associated amyloid, we do not recommend extensive follow-up testing for systemic amyloidosis or more aggressive therapy than would be indicated for other MALT lymphomas of similar clinical stage.

Anomalous PiB enhancement in the superior sagittal and transverse venous sinuses

Pittsburgh compound-B (PiB), an amyloid-binding positron emission tomography (PET) tracer, is widely used for imaging amyloid-β in those with and at risk for Alzheimer disease. Here, we report on an otherwise normal 68-year-old female with abnormally high and very focal PiB retention. Coregistered T1-weighted magnetic resonance imaging and dynamic 2-fluoro-2-deoxy-D-glucose (FDG) images confirmed that the focal PiB enhancement was in the superior sagittal and transverse sinuses, outside of the adjacent cortex. Flow through the venous vasculature was normal as assessed by dynamic FDG PET imaging. These features supported the conclusion that PiB retention was not simply due to a hemodynamic abnormality, but may have represented PiB binding to fibrillar deposits of a β-sheet protein (ie, amyloid), whose nature is currently unclear.

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.

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue arising in the lateral ventricle

Extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) lymphomas are a well-described type of low-grade B-cell non-Hodgkin lymphoma. They typically arise adjacent to mucosal surfaces in the gastrointestinal tract, lung and conjunctiva, and, less frequently, in the skin, salivary gland and thyroid gland. Unusual locations, such as the genitourinary tract, thymus and meninges, have also been reported. We recently encountered a case of an intracranial MALT lymphoma in a 53-year-old man who presented with persistent headaches and a seizure. The lesion developed as a mass within the lateral ventricle, appeared to be arising from the choroid plexus, and was not associated with meninges. Histologically, there was a vaguely nodular, dense lymphoid infiltrate with occasional benign follicles colonized by marginal zone lymphoma, suggesting derivation from a focus of prior inflammation. Translocations involving the MALT1 gene were not identified but karyotypic evaluation highlighted a complex cytogenetic profile with many chromosomal abnormalities. This rare case provides insight into the pathophysiology of MALT lymphomas.

Primary lymphoblastic B-cell lymphoma of the cranial dura mater: a case report and review of the literature

Primary lymphomas of the cranial dura mater are rare. Mucosa-associated lymphoid tissue extranodal marginal zone lymphomas are the most common subtype of non-Hodgkin's lymphomas that present as primary cranial dura tumors. A 33 year-old male presented with a 3-month history of a growing lump in the right frontal area. Neuroimaging studies demonstrated an extra-axial, broad-based mass with a dural tail in the right frontal bone convexity. Biopsy led to the diagnosis of localized dural precursor B-cell lymphoblastic lymphoma. The patient was treated with a combination of chemotherapy and radiotherapy, achieving durable disease-free survival. This is the first report of precursor B-cell lymphoblastic lymphoma of dura mater. A review of the literature on primary lymphomas of cranial dura mater is presented. Primary lymphomas of the cranial dura mater are rare. Mucosa-associated lymphoid tissue extranodal marginal zone lymphomas are the most common subtype of non-Hodgkin's lymphomas that present as primary cranial dura tumors. A 33 year-old male presented with a 3-month history of a growing lump in the right frontal area. Neuroimaging studies demonstrated an extra-axial, broad-based mass with a dural tail in the right frontal bone convexity. Biopsy led to the diagnosis of localized dural precursor B-cell lymphoblastic lymphoma. The patient was treated with a combination of chemotherapy and radiotherapy, achieving durable disease-free survival. This is the first report of precursor B-cell lymphoblastic lymphoma of dura mater. A review of the literature on primary lymphomas of cranial dura mater is presented.

[Follicular dural lymphoma. Case report]

A case of a meningeal B-cell lymphoma is described. A 48-year-old man presented with an episode of grand mal seizure following a brain injury. An initial diagnosis of extradural hematoma was made based on the results of the cerebral computerized tomography scan. Magnetic resonance images demonstrated an enhanced mass with a dural tail attached to the meningeal layer of the temporal bone, suggesting a meningioma "en plaque". The mass was surgically excised. Tumoral removal was subcomplete (Simpson 2). Operative inspection also suggested a meningioma, but histological analysis and electron microscopy revealed a grade IV follicular B-cell lymphoma. Biological studies were normal. An extensive workup found an external iliac adenopathy with several osseous locations on PET. The patient underwent chemotherapy and radiotherapy. Three years after the first symptoms appeared, the patient is alive and free of symptoms. The clinicopathological features and treatments were discussed.

Primary central nervous system marginal zone B-cell lymphoma of the Basal Ganglia mimicking low-grade glioma: a case report and review of the literature

Primary central nervous system (CNS) marginal zone B-cell lymphoma (MZBL) is very rare and shows an indolent disease course with potential of being cured. It seems to originate from meningothelial cells, and the most common site of occurrence is the dura of the cerebral convexity. Primary CNS MZBL is often misdiagnosed as meningioma because of its similar tumor locations and appearances on magnetic resonance imaging (MRI). Surgery, radiation therapy, chemotherapy, and combinations of these are considered treatment modalities depending on the case. Herein, we describe an 18-year-old man who presented with acute onset of right-sided central facial nerve palsy, right-sided hemiparesis with motor power grade 4+, dizziness, and dysarthria. After an MRI scan of the brain, wherein he was first diagnosed with high-grade glioma, a biopsy sample showed that he had primary CNS MZBL arising in the left basal ganglia. He was treated with radiation therapy, which resulted in complete remission for 1 year and 10 months up to the date of this case report. It is important to diagnose primary CNS MZBL correctly because it is curable without unnecessary invasive treatment in cases of localized disease.

Immunoglobulin derived depositions in the nervous system: novel mass spectrometry application for protein characterization in formalin-fixed tissues

Proteinaceous deposits are occasionally encountered in surgically obtained biopsies of the nervous system. Some of these are amyloidomas, although the precise nature of other cases remains uncertain. We studied 13 cases of proteinaceous aggregates in clinical specimens of the nervous system. Proteins contained within laser microdissected areas of interest were identified from tryptic peptide sequences by liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS). Immunohistochemical studies for immunoglobulin heavy and light chains and amyloidogenic proteins were performed in all cases. Histologically, the cases were classified into three groups: 'proteinaceous deposit not otherwise specified' (PDNOS) (n=6), amyloidoma (n=5), or 'intracellular crystals' (n=2). LC-MS/MS demonstrated the presence of lambda, but not kappa, light chain as well as serum amyloid P in all amyloidomas. lambda-Light-chain immunostaining was noted in amyloid (n=5), although demonstrable monotypic lymphoplasmacytic cells were seen in only one case. Conversely, in PDNOS kappa, but not lambda, was evident in five cases, both light chains being present in a single case. In three cases of PDNOS, a low-grade B-cell lymphoma consistent with marginal zone lymphoma was present in the brain specimen (n=2) or spleen (n=1). Lastly, in the 'intracellular crystals' group, the crystals were present within CD68+ macrophages in one case wherein kappa-light chain was found by LC-MS/MS only; the pathology was consistent with crystal-storing histiocytosis. In the second case, the crystals contained immunoglobulin G within CD138+ plasma cells. Our results show that proteinaceous deposits in the nervous system contain immunoglobulin components and LC-MS/MS accurately identifies the content of these deposits in clinical biopsy specimens. LC-MS/MS represents a novel application for characterization of these deposits and is of diagnostic utility in addition to standard immunohistochemical analyses.

Extranodal marginal zone lymphoma of the dura mater with IgH/MALT1 translocation and review of literature

Primary central nervous system lymphoma (PCNSL) is an extranodal non-Hodgkin lymphoma involving brain, intraocular structures and spinal cord, without evidence of systemic disease. The majority of PCNSLs are diffuse large B-cell type. We encountered a rare case of primary dural marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) with extension into the brain in a 59-year-old man. A magnetic resonance imaging scan showed a 22-mm tumor located in the left posterior temporal lobe extending from the dura. Histopathology revealed a lymphoplasmacytic infiltration of the dura and the brain parenchyma in a perivascular pattern. Immunohistochemical and in situ hybridization studies showed a B-cell phenotype with kappa light chain restriction. Fluorescent in situ hybridization study showed a t(14;18)(q32;q21) with immunoglobulin heavy-chain/MALT1 fusion. The molecular study for immunoglobulin heavy-chain gene rearrangement by polymerase chain reaction showed a clonal gene rearrangement.

Primary leptomeningeal B-cell lymphoma of MALT-type in statu nascendi: a case report and review of the literature

A 29-year-old Caucasian female suffering from bipolar disorder, mixed, moderate with psychotic features (DSM-IV 296.64) and panic disorder without agoraphobia (DSM-IV 300.01) died as a result of an accidental overdose. Upon histopathological examination of the brain, as an incidental finding, a small lesion (1mm x 2mm) composed of heterogeneous small lymphocytic cells (CD20-positive) including centrocyte-like cells, a few small lymphocytes and rare immunoblast-like cells was evident. The diagnosis of primary leptomeningeal MALT-type lymphoma was made. Due to its small size and lack of space-occupying characteristics, the lesion is considered to be in statu nascendi. This case adds another aspect to the rare entity of primary leptomeningeal lymphomas.

Overview of monoclonal gammopathies of undetermined significance

Among the B-cell lymphoproliferative disorders, monoclonal gammopathy of undetermined significance (MGUS) is the humoral counterpart to monoclonal B-cell lymphocytosis. This review introduces the papers from the section devoted to MGUS at the International Workshop entitled 'Monoclonal B-cell lymphocytosis and chronic lymphocytic leukaemia: environmental and genetic risk factors.'

Primary malignant B-cell–type dural lymphoma: case report

BACKGROUND

The primary malignant dural lymphoma of B-cell type is rare. Our review of the literature (24 cases) indicated that patients with this tumor had female predominance, immunocompetency, and longer survival compared with those with primary malignant intracerebral lymphomas. Based on its clinicopathological features, this dural lymphoma may be classified differently from other types of malignant lymphomas in the central nervous system.

CASE DESCRIPTION

The authors report an example of a patient who had a favorable course of malignant dural lymphoma. A 59-year-old woman presented with primary malignant dural lymphoma in the frontal area. Histological diagnosis was a diffuse large B-cell-type lymphoma of intermediate malignancy, but MIB-1 index was extremely high. Subtotal tumor removal was followed by 4 courses of chemotherapy. Thirty months after surgery, the patient is asymptomatic with no MRI evidence of recurrence. A combination of subtotal resection and chemotherapy for a primary malignant dural lymphoma is an effective means to attempt cure of this tumor.

CONCLUSION

These rare tumors may be managed successfully by subtotal resection and postoperative treatment. We believe that chemotherapy is the treatment of choice after subtotal resection of malignant dural lymphomas, as experienced in our case.

Primary diffuse large B-cell lymphoma of the dura mater and cranial vault

✓ Primary high-grade lymphoma of the dura mater and cranial vault has rarely been reported. The authors treated a 61-year-old man who presented with a slow-growing scalp mass that involved the cranial vertex. Magnetic resonance imaging revealed an oval mass of the dural type with peripheral edema in the bilateral parietal region, with attachment to the cranial vault and extension to the subgaleal space. After subtotal resection, pathological examination yielded a diagnosis of malignant large B-cell lymphoma. Twenty-three months postoperatively, after undergoing radiation therapy and chemotherapy, the patient is neurologically intact and without systemic dissemination of the malignancy. This is a case of primary malignant B-cell lymphoma of the dura mater with extensive involvement of the skull, which is a very rare event. Imaging-based diagnosis and combined therapy consisting of surgery, radiation therapy, and chemotherapy for the disease are discussed, and the literature on extraaxial malignant lymphomas is extensively reviewed.

Primary dural lymphomas: a review

✓Primary dural lymphoma (PDL) is a rare subtype of primary central nervous system lymphoma (PCNSL) that arises from the dura mater and differs biologically from other CNS lymphomas. The PDL is usually a low-grade marginal zone lymphoma (MZL), whereas other types of PCNSLs are usually high-grade, diffuse, large B-cell lymphomas. A PDL usually presents with single or multiple extraaxial masses that enhance diffusely with addition of contrast material and can be confused with meningioma. The MZLs respond well to local therapy such as surgery and radiation treatment. Most patients attain complete response and have good local disease control. Nevertheless, the risk of systemic relapse appears to be high, probably because the dura mater is outside of the blood–brain barrier.

Intracranial non-Hodgkin's MALT lymphoma mimicking a large convexity meningioma

Primary presentation of an intradural Non-Hodgkin's lymphoma is rare. Recently these B cell lymphomas of mucosa associated lymphoid tissue (MALT) have gained acceptance as an important pathological subtype and are distinguishable from other primary CNS lymphomas that exhibit aggressive behaviour. Over the past decade a number of these lesions have been reported to resemble a meningioma both intra-operatively and radiologically. The authors outline such a case of marginal zone B cell lymphoma that clinically and radiologically resembled a meningioma. This case 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, if appropriate targeted therapy is to be administered.

Clinicopathologic and genetic profile of intracranial marginal zone lymphoma: a primary low-grade CNS lymphoma that mimics meningioma

PURPOSE

Although rare overall, marginal zone B-cell lymphoma (MZBCL) is the most common primary low-grade CNS lymphoma reported in the literature. The aim of this study is to elucidate the biology and genetic features of this unusual tumor.

PATIENTS AND METHODS

Fifteen CNS MZBCLs were studied clinically, pathologically, and genetically, including fluorescent in situ hybridization analyses with commercially available MALT1 and IgH break-apart and centromere 3, 7, 12, and 18 probes.

RESULTS

CNS MZBCLs preferentially affect middle-aged women (female-to-male ratio, 4:1), with 93% presenting as dural-based masses mimicking meningioma. Ten patients with 1 to 7.6 years of follow-up after diagnosis showed no evidence of disease after radiation and/or chemotherapy. Like MZBCLs outside of the CNS, they consisted of CD20+, CD3- small B lymphocytes with varying degrees of plasmacytic differentiation and predominantly kappa light-chain restriction (78%). Lymphoid follicles with follicular colonization were seen in three patients and deposition of amyloid was noted in samples from two patients, one of which was tumefactive. Neither Bcl-6 protein nor Epstein-Barr virus-encoded RNA was expressed. Trisomy 3 was detected in six of 12 patients, with no rearrangements of MALT1 or IgH and no trisomies of 7, 12, or 18 detected.

CONCLUSION

Our data suggest that intracranial MZBCL is an indolent primary CNS lymphoma that typically presents as a meningioma-like dural-based mass. Trisomy 3, but not MALT1 or IgH translocation, is a common genetic abnormality that may contribute to the pathogenesis of this CNS lymphoma.