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Clinical activity of rituximab in extranodal marginal zone B-cell lymphoma of MALT type.

The clinical activity of rituximab has been evaluated in a phase 2 study in both untreated and relapsed mucosa-associated lymphoid tissue (MALT) lymphomas. Treatment consisted of 4 standard (375 mg/m2) weekly doses. Thirty-five patients were enrolled, and 34 completed the treatment program. The primary lymphoma location was stomach in 15 patients, and extragastric in 20. Eleven patients had previously been treated with chemotherapy. At study entry 12 patients had Ann Arbor stage IE, 3 had stage IIE, and 20 had stage IV disease. The overall response rate was 73% (95% confidence interval, 56%-87%), with 15 complete responses and 10 partial responses, and the response rate was significantly higher in the chemotherapy-naive patients, who had an 87% response rate compared with 45% of the previously treated patients (P =.03). The median response duration was 10.5 months. At a median follow-up of 15 months, 9 patients (26%) relapsed. The median time to treatment failure was 14.2 months in the whole series, but it was significantly longer (22 versus 12 months) in the chemotherapy-naive patients compared with those who had prior chemotherapy (P =.001). Most adverse events were of mild to moderate severity with no grade 4 toxicity. This study indicates that rituximab is safe with significant activity in MALT lymphomas.

Adult↗

Oral chlorambucil for extranodal, marginal zone, B-cell lymphoma of mucosa-associated lymphoid tissue of the orbit.

PURPOSE: To report the outcome of oral chlorambucil as a single treatment in patients with orbital mucosa-associated lymphoid tissue (MALT) lymphoma. DESIGN: Retrospective nonrandomized clinical study. PARTICIPANTS: Thirty-three patients with isolated orbital MALT lymphoma. METHODS: Medical records of all patients with histology-verified orbital MALT lymphoma treated with oral chlorambucil at the Royal Melbourne Hospital were reviewed. MAIN OUTCOME MEASURES: Complete clinical response, partial response, local relapse, systemic extension (distant relapse), and survival. RESULTS: Thirty-three patients (19 female; mean age, 69 years) participated in the study. Patients received an average of 4 courses of oral chlorambucil with a mean total dose of 600 mg. The lacrimal gland was the most frequent site of occurrence (24%), followed by the conjunctiva, eyelid, and superior orbit. Orbital mass, swelling, and diplopia were common presenting signs. Complete response was noted in 26 patients (79%). In 2 of the patients with complete clinical response, mild residual thickening was noted on follow-up orbital imaging studies. Four patients (12%) showed disease recurrence or relapse. Mean follow-up time was 32 (+/-20) months (range, 8 months-6 years; median, 26 months). None of the patients developed granulocytopenia secondary to chemotherapy, and none suffered significant nausea or vomiting. One patient with malignant transformation died 12 months after diagnosis and initial treatment. CONCLUSIONS: Systemic chemotherapy with chlorambucil is a reasonable option in patients with orbital MALT lymphoma. It is associated with minimal to no side effects. Additionally, it may be well tolerated by elderly patients and also may treat subclinical disease elsewhere.

Administration, Oral↗

Primary thymic extranodal marginal-zone B-cell lymphoma of mucosa-associated lymphoid tissue type exhibits distinctive clinicopathological and molecular features.

Extranodal marginal-zone B-cell lymphoma (MZBL) of mucosa-associated lymphoid tissue (MALT) arising in the thymus is rare, with the largest series in the literature including only three cases. In the present study, we investigated 15 cases of thymic MALT lymphoma to systematically characterize its clinical, histopathological, and molecular features. There was a marked female predilection (male:female = 1:4), with a mean age of 55 years at diagnosis. There was a strong association with autoimmune disease, especially Sjögren's syndrome. Histologically, the thymic lymphoma showed the characteristic morphological features of extranodal MZBL of MALT type. Cysts were common. Prominent lymphoepithelial lesions were formed by centrocyte-like cells infiltrating and expanding the Hassall's corpuscles and epithelium lining the cysts. Plasmacytic differentiation was apparent in all cases. Notably, 13 of 15 cases expressed immunoglobulin (Ig) A phenotype; IgA expression in thymic MALT lymphoma was in striking contrast with the IgM phenotype observed in most of the Sjögren's syndrome-associated MZBLs and MALT lymphomas at other sites. Epstein-Barr virus was absent, and API2-MALT1 gene fusion, a recently reported MALT lymphoma-specific gene abnormality, was not detected in any case. Although one patient died of disease 85 months after the diagnosis, other patients were alive with overall 3-year and 5-year survival rates being 89% and 83%, respectively. Among the 22 patients reported previously and in the present series, at least 17 patients (77%) were Asians. These data indicate that thymic MALT lymphoma may represent a distinct subgroup of MALT lymphoma characterized by apparent predilection for Asians, a strong association with autoimmune disease, frequent presence of cysts, consistent plasma cell differentiation, tumor cells expressing IgA phenotype, and consistent lack of API2-MALT1 gene fusion.

Adult↗

Molecular diagnostics in low-grade gastric marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type after Helicobacter pylori eradication therapy.

The primary gastric lymphomas are extranodal non-Hodgkin's lymphomas that likely originate from the mucosa-associated lymphoid tissue (MALT). Data suggest that chronic infection with Helicobacter pylori (H pylori) is significantly associated with the pathogenesis of low-grade gastric MALT lymphomas. This is in keeping with the observation that many patients with early low-grade MALT lymphomas have complete remissions after H pylori eradication therapy. However, the stability of these remissions remains unclear and relapses have been reported. It can be difficult to distinguish between early malignant and benign disorders of the gastric mucosa. A polymerase chain reaction (PCR) assay can detect rearrangements of the variable region of immunoglobulin heavy chains. This assay can be used to distinguish the clonality of B lymphocytes and has been investigated as a test for differential diagnosis of MALT lymphomas. Monoclonality is observed in the majority of MALT-lymphoma samples at diagnosis but has been found in gastritis samples as well. Whether the presence of monoclonal B cells is associated with the risk of lymphoma progression remains unclear. As many as 50% of patients who have complete histologic remissions of MALT lymphoma after H pylori eradication therapy have persisting monoclonal bands in follow-up PCR monitoring. Although it is unclear as to whether monoclonality indicates the presence of minimal residual disease, patients who have persistent monoclonal bands during follow-up should be considered at risk for relapse. The PCR assay for rearrangements of the variable region of the immunoglobulin heavy-chain gene appears to be of low value in the diagnosis of B-cell malignancies but could provide a useful tool in the follow-up of patients who achieve remissions after H pylori eradication.

Anti-Bacterial Agents↗

Nongastric marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue.

A retrospective survey of patients with pathologically reviewed extragastric mucosa-associated lymphoma tissue (MALT) lymphomas from 20 institutions was performed. A total of 180 patients with histologically confirmed diagnosis of extragastric MALT lymphomas were studied. Their median age was 59 years (range, 21-92 years). Ann Arbor stage I disease was present in 115 patients (64%) and stage II disease in 16 (9%). Most cases were in the low or low-intermediate risk groups according to the International Prognostic Index (IPI). Forty-one (23%) patients had involvement of more than one extranodal site at diagnosis and in 24 cases (13%) the lymphoma presented at multiple mucosal sites (9 of them with only mucosal involvement, without bone marrow or nodal disease). Lymph node involvement was present in 21%. Patients were treated with a variety of therapeutic strategies, including chemotherapy in 78 cases. The median overall survival (OS) was not reached; the 5-year OS rate was 90% (95% CI, 82%-94%), the 5-year cause-specific survival (CSS) was 94% (95% CI, 87%-97%), and the 5-year progression-free survival (PFS) was 60% (95% CI, 50%-70%). Multivariate analysis showed that Ann Arbor stage was significantly associated with longer OS, nodal involvement with longer CSS, and favorable IPI score with better PFS. At a median follow-up of 3.4 years, 48 patients (27%; 95% CI, 20%-34%) had a relapse, 6 (3%; 95% CI, 1%-7%) showed histologic transformation, and 18 (10%; 95% CI, 6%-15%) experienced the development of a second tumor. Our data confirm the indolent nature of nongastric MALT lymphomas and the high rate of patients presenting with disseminated disease, which, when limited to mucosal sites, was not associated with a poorer outcome.

Adult↗

Treatment of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type with cladribine: a phase II study.

PURPOSE: As chemotherapy has not been extensively studied in patients with lymphoma of the mucosa-associated lymphoid tissue (MALT), we initiated a prospective study to evaluate the activity of the nucleoside analog cladribine (2-chlorodeoxyadenosine [2-CdA]) in this disease. PATIENTS AND METHODS: Patients with histologically verified MALT-type lymphoma were enrolled. 2-CdA was administered at a dose of 0.12 mg/kg body weight on 5 consecutive days, as a 2-hour infusion. Cycles were repeated every 4 weeks for a maximum of six cycles. RESULTS: Nineteen patients with gastric and seven patients with extragastric MALT lymphoma were enrolled. All patients were chemotherapy-naive, and two had been locally irradiated before systemic relapse of the lymphoma. A total of 102 cycles was administered to our patients (median number of cycles per patient, four). All 25 assessable patients responded to treatment: 21 patients (84%) achieved complete remission (CR) and four patients achieved partial remission. All patients (100%) with gastric presentation, but only three patients (43%) with extragastric presentation, achieved CR. Toxicities were moderate and mainly hematologic and required dose reduction and/or premature discontinuation of therapy in only three cases. Two patients died from vascular events, one shortly after the first cycle because of myocardial infarction and the other from stroke 3 months after the second course. Three patients relapsed after 13, 18, and 22 months and one patient showed progressive disease after 15 months. At present, 24 patients are alive at a median follow-up time of 32 months. CONCLUSION: Our data demonstrate that 2-CdA is highly effective in inducing CR in 84% of patients with MALT-type lymphoma.

Adult↗

Treatment of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) with mitoxantrone, chlorambucil and prednisone (MCP).

BACKGROUND: Mucosa-associated lymphoid tissue (MALT) lymphoma is a relatively common type of lymphoma arising in various tissues throughout the human body. Currently, there is no standard chemotherapy for advanced stage MALT lymphoma. This has prompted us to retrospectively analyse our experience with the MCP regimen (mitoxantrone, chlorambucil and prednisone) in patients with MALT lymphoma. PATIENTS AND METHODS: Patients with histologically verified MALT lymphoma undergoing chemotherapy with MCP were evaluated retrospectively. The MCP regimen consists of mitoxantrone 8 mg/m(2) intravenously on days 1 and 2, chlorambucil 3 x 3 mg/m(2) per os (p.o.) on days 1-5 and prednisone 25 mg/m(2) p.o. on days 1-5. Information analysed included localisation of the lymphoma, clinical stage, pretreatment, number of chemotherapy cycles administered, toxicity, response to treatment, follow-up time, relapse and survival. RESULTS: A total of 15 patients (six females and nine males aged between 34 and 88 years) with histologically ascertained MALT lymphoma undergoing treatment with the MCP regimen were identified from our records. Ten patients had extragastric lymphoma, while five patients suffered from gastric MALT lymphoma. All patients were chemotherapy-naïve, while two had been locally irradiated before application of MCP for recurrent disease. A total of 74 cycles was administered to our patients, with a median number of five cycles per patient. Eight (53%) patients achieved complete remission, six (40%) patients partial response and only one (7%) patient had progressive disease. Subjective tolerance was excellent, and toxicities were mainly haematological, including granulocytopenia World Health Organisation grade 3 and 4 in three patients each. In two patients, this was accompanied by single episodes of uncomplicated herpes simplex infection. At the time of analysis, all patients are still alive. No relapses have occurred after a median follow-up time of 16 (range 12-29) months. CONCLUSIONS: Our data suggest that MCP is an effective and well-tolerated regimen for treatment of patients with MALT lymphoma irrespective of localisation. Judging from our data, MCP also appears to be a feasible regimen in elderly patients.

Administration, Oral↗

111In-DOTA- dPhe1-Tyr3-octreotide, 111In-DOTA-lanreotide and 67Ga citrate scintigraphy for visualisation of extranodal marginal zone B-cell lymphoma of the MALT type: a comparative study.

Somatostatin receptor (SSTR) scintigraphy and gallium-67 citrate ((67)Ga) scintigraphy have been used for visualisation of Hodgkin's lymphoma and non-Hodgkin's lymphoma. However, experience with B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) type is very limited. The aim of this study was to prospectively compare the (67)Ga scintigraphy results with those obtained by (111)In-DOTA- dPhe(1)-Tyr(3)-octreotide ((111)In-DOTA-TOCT) and (111)In-DOTA-lanreotide ((111)In-DOTA-LAN) scintigraphy in patients with proven MALT-type lymphoma. Comparative scintigraphic examinations using (67)Ga, (111)In-DOTA-TOCT and (111)In-DOTA-LAN were performed in 18 patients (11 female and 7 male, median age 64+/-15 years) with histologically verified MALT-type lymphomas of various origin. Planar and single-photon emission tomography imaging acquisitions were performed after injection of a mean dose of 185+/-26 MBq (67)Ga and 165+/-20 MBq (111)In-DOTA-TOCT or (111)In-DOTA-LAN. All scintigraphic results were correlated with other conventional examinations including gastroscopy, colonoscopy, endosonoscopy, ophthalmologic investigation, CT of the thorax and abdomen and bone marrow biopsy. This comparative study showed that (67)Ga scintigraphy found abnormalities in 10 of 16 patients (63%) and detected 18 of 31 clinically involved sites (58%), but was false positive in three patients. (111)In-DOTA-TOCT found abnormalities in 9 of 15 patients (60%) and detected 15 of 27 clinical lesions (56%); it was false positive in two patients. (111)In-DOTA-LAN scintigraphy showed abnormalities in 7 of 11 patients (64%) and found 12 of 22 clinical lesions (55%). False-positive (111)In-DOTA-LAN scan results were found in two patients. For supra-diaphragmatic lesions, (67)Ga scintigraphy detected 12 of 16 sites (75%). (111)In-DOTA-TOCT scintigraphy revealed 7 of 15 lesions (47%). (111)In-DOTA-LAN showed 6 of 12 positive sites (50%). For infra-diaphragmatic involvement, the sensitivities of (67)Ga, (111)In-DOTA-TOCT and (111)In-DOTA-LAN were 40%, 67% and 60%, respectively. It is concluded that MALT-type lymphoma can be visualised by (67)Ga, (111)In-DOTA-TOCT and (111)In-DOTA-LAN scintigraphy. Although there were no statistically significant differences in patient-related and site-related sensitivities when using (67)Ga compared with (111)In-DOTA-TOCT and (111)In-DOTA-LAN, the sensitivity of (67)Ga tended to be superior to that of (111)In-DOTA-TOCT and (111)In-DOTA-LAN for supra-diaphragmatic lesions but inferior for infra-diaphragmatic involvement. In selected cases, the combination of (67)Ga and (111)In-DOTA-LAN or (111)In-DOTA-TOCT may increase the diagnostic efficiency in patients with MALT-type lymphoma.

Adult↗

Somatostatin-receptor scintigraphy for staging and follow-up of patients with extraintestinal marginal zone B-cell lymphoma of the mucosa associated lymphoid tissue (MALT)-type.

The majority of lymphomas of the mucosa-associated lymphoid tissue (MALT)-type arise in the stomach, but extragastric locations are also frequently encountered. Due to previous results indicating that somatostatin receptor (SSTR)-expression distinguishes between gastric and extragastric MALT-type lymphoma, we have initiated a study to evaluate the role of SSTR-scintigraphy for staging and follow-up of patients with extragastric manifestations of MALT-type lymphoma. A total of 30 consecutive patients, including 24 with primary extragastric MALT-type lymphoma, 5 patients with dissemination to extragastric sites (including colon, lung, parotid, ocular adnexa and breast) following an initial gastric MALT-lymphoma and one patient with spread to stomach, lung and lymph nodes following parotid lymphoma were prospectively studied. All patients had histologically verified MALT-type lymphoma: 2 patients had lymphoma presenting in the lung, 9 in the ocular adnexa, 7 had lymphomas in the parotid, 2 patients had disease located in the breast, 3 patients had lymph-node relapse following MALT-type lymphoma of the parotid, the lacrimal gland and the thyroid, and 1 had primary MALT-lymphoma of the liver. All patients underwent SSTR-scintigraphy using (111)In-DTPA-D-Phe(1)-Octreotide ((111)In-OCT) before initiation of therapy, while 13 also had a second scan after treatment. The results of gamma camera imaging were compared to conventional staging. No positive scans could be obtained in patients with dissemination following gastric lymphoma, while all patients with primary extragastric lymphoma had positive scans at the site of histologically documented involvement before initiation of therapy. In addition, also the patient with secondary spread to stomach, lung and lymph nodes was positive in all documented lymphoma sites. In one patient, focal tracer uptake in projection to the maxillary sinus was documented, which was bioptically verified as inflammation. In the scans performed after therapy, focal tracer accumulation in the left orbit indicated persistence of disease following irradiation in one patient with otherwise negative work-up, which was verified by MRI and biopsy 6 months later. In another patient, a positive scan indicated disease relapse in the lacrimal gland 9 months before clinical verification by means of ultrasound. In one patient, a focus not present in the pretherapeutic scan was found in the ethmoidal sinus, corresponding to a hyperplastic polyp. Both SST-scan as well as CT indicated disease persistence in one case, while negative scans corresponding to complete remission as judged by conventional staging were obtained following therapy in the remaining patients, and absence of relapse has been confirmed for a median follow-up of 2 years. These results indicate that (111)In-OCT is an excellent tool for staging and non-invasive therapy-monitoring in extragastric MALT-type lymphomas. These data further confirm our initial finding that gastric MALT-type lymphomas do not express relevant amounts of respective SSTR, and that SSTR-scanning is able to distinguish between gastric vs extragastric origin of MALT-type lymphoma irrespective of the site of presentation.

Adult↗

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.

Adult↗

A common clonal origin of nodal marginal zone B-cell lymphoma and plasma cell myeloma demonstrating different immunophenotypes: a case report of composite lymphoma.

We demonstrated an 83-year-old male case of composite lymphoma. Before 18 years, he was diagnosed with nodal marginal zone B-cell lymphoma in the cervical lymph node. Peripheral blood showed anemia and IgA (kappa)-type monoclonal gammopathy (IgA; 3,625 mg/dL). Bone marrow aspiration biopsy exhibited plasma cell myeloma, in which atypical plasma cells were positive for cytoplasmic IgA (kappa) and atypical lymphoid cells intermingled were positive for CD20. In contrast, cervical lymph node biopsy revealed nodal marginal zone B-cell lymphoma, in which lymphoma cells were positive for cytoplasmic IgG (lambda). Southern blotting analysis of the IgH gene showed same clonal rearrangement band in both lymph node and bone marrow samples and additional band in the bone marrow. Sequence analyses of the IgH gene showed an identical sequence of CDR3 in both samples. Thus, we demonstrated a common clonal origin of composite lymphoma comprising nodal marginal zone B-cell lymphoma and plasma cell myeloma. Nodal marginal zone B-cell lymphoma recurred in cervical lymph node and involved into the bone marrow, differentiating into plasma cell myeloma in which Ig isotype switched and monoclonal gammopathy developed. Sequence analysis of the IgH gene was a powerful tool for determination of clonal origin.

Aged↗

Primary cutaneous marginal zone B-cell lymphoma: clinical and therapeutic features in 50 cases.

BACKGROUND: Primary cutaneous marginal zone B-cell lymphoma (PCMZL) is a low-grade B-cell lymphoma that originates in the skin, with no evidence of extracutaneous disease. Studies focusing on the optimal treatment of PCMZL have not been published thus far. We describe 50 patients with PCMZL to further characterize clinical characteristics and outcome and, in particular, to evaluate our current therapeutic approach. OBSERVATIONS: The majority of the patients (36/50 [72%]) presented with multifocal skin lesions, and 14 patients (28%) presented with solitary or localized lesions. The initial treatment of patients with solitary lesions consisted of radiotherapy or excision, whereas patients with multifocal lesions received a variety of initial treatments, most commonly radiotherapy and chlorambucil therapy. Cutaneous relapses developed in 19 (48%) of 40 patients who had complete remission and were more common in patients with multifocal disease. After a median period of follow-up of 36 months, 2 patients developed extracutaneous disease, but none of the patients died of lymphoma. CONCLUSIONS: Patients with PCMZL who have solitary lesions can be treated effectively with radiotherapy or excision. For patients with PCMZL who have multifocal lesions, chlorambucil therapy and radiotherapy are suitable therapeutic options. In case of cutaneous relapses, the beneficial effects of treatment should carefully be weighed against the potential adverse effects.

Adult↗

Absence of ATM deletions in 16 cases of splenic marginal-zone B-cell lymphoma (SMZBCL).

We present the study of 16 cases of splenic marginal zone B-cell lymphoma (SMZBL) combining conventional cytogenetics and fluorescence in situ hybridization technique (FISH). We used a locus specific probe (11q22.3) that hybridizes with Ataxia Telangiectasia Mutated gene (ATM) and a centromeric probe of chromosome 11 as a control. Deletions in ATM gene region have been found in B-cell chronic lymphocytic leukemia (B-CLL) and mantle cell lymphoma (MCL) and have been considered as an independent prognosis factor in these pathologies. The aim of our study was to determine the ATM status in SMZBL because no specific studies concerning ATM status in SMZBL have been reported and other B-cell malignances have shown ATM deletions. No deletions were detected in any of the 16 cases. ATM deletions could be considered a rare event in SMZBCL.

Ataxia Telangiectasia Mutated Proteins↗

Numerical cytogenetic abnormalities of chromosomes 3, 7, and 12 in marginal zone B-cell lymphomas.

Monocytoid B-cell lymphoma, low-grade B-cell lymphoma of mucosa-associated lymphoid tissue, and primary splenic marginal zone cell lymphoma (SMZCL) were originally described as distinct clinicopathologic entities. On the basis of morphologic and immunologic similarities, monocytoid B-cell lymphoma and lymphoma of mucosa-associated lymphoid tissue recently have been grouped together as nodal and extranodal types of marginal zone B-cell lymphomas (MZBCLs) in the Revised European-American Classification of Lymphoid Neoplasms. Primary SMZCL, although related, is considered a separate provisional entity. Trisomies 3, 7, and 12 are common in non-Hodgkin's lymphomas. Several recent studies reported that MZBCLs arising in sites of mucosa-associated lymphoid tissue have a high frequency of trisomy 3. To assess whether similar numerical cytogenetic abnormalities are present in MZBCLs with prominent monocytoid B-cell cytologic features, we performed a retrospective study, using formalin-fixed, paraffin-embedded tissue blocks from 36 cases. By use of fluorescence in situ hybridization to detect chromosome trisomies, we identified trisomy 3 in 11 (85%) of 13 extranodal MZBCLs with monocytoid B cells (MZBCL-Es), in 6 (50%) of 12 nodal MZBCLs of monocytoid B-cell type (MZBCL-Ns), but in only 2 (18%) of 11 SMZCLs. Trisomies 7 and 12 were found at lower frequencies. These data suggest that trisomy 3 is a common numerical chromosomal abnormality of MZBCL-Es and MZBCL-Ns with monocytoid B-cell features. Despite similar morphologic and immunophenotypic characteristics, the low incidence of trisomy 3 in the SMZCL cases implies that this process may be genetically distinct.

Cell Line↗

Splenic marginal zone B-cell lymphoma associated with primary Sjögren's syndrome.

We describe a 67-year-old woman with primary Sjögren's syndrome who developed a splenic marginal zone B-cell lymphoma, and complained of a dry mouth and Raynaud's phenomenon. She had splenomegaly, swollen lymph nodes and monoclonal IgM-kappa cryoglobulin. After splenectomy, Raynaud's phenomenon had improved with the decrease of cryoglobulin. This is the first case of primary Sjögren's syndrome with splenic marginal zone B-cell lymphoma to be reported.

Aged↗

Eradication of Borrelia burgdorferi infection in primary marginal zone B-cell lymphoma of the skin.

Primary cutaneous B-cell lymphomas have been associated with Borrelia burgdorferi, the spirochete responsible for Lyme disease. Recently, cutaneous marginal zone B-cell lymphoma has been proposed as a distinct clinical-pathological entity. We report a case of primary cutaneous marginal zone lymphoma, associated with B burgdorferi infection. Polymerase chain reaction (PCR) amplification of the third complementarity determining region (CDR3) of the immunoglobulin heavy chain gene showed the presence of a monoclonal lymphoproliferation, therefore strengthening the histological diagnosis of a malignant process. B burgdorfer-specific hbb gene sequences were detected by PCR in the lymphoma tissue at diagnosis but not after antibiotic treatment. A nearly complete clinical and histological regression was observed after B burgdorferi eradication, with immunohistochemistry studies showing disappearance of plasma cell differentiation and a marked decline in the number of CD3+ T cells and Ki-67+ cells. Our case confirms the link between B burgdorferi and some cutaneous lymphomas. The disappearance of the microorganism accompanied by the unequivocal decrease of most indicators of active T- and B-cell immune response strongly supported a pathogenetic role for B burgdorferi in sustaining an antigen-driven development and growth of this cutaneous marginal zone lymphoma. Antibiotic therapy (analogous to Helicobacter pylori infection in gastric MALT lymphoma) might be helpful with the aim of averting or at least deferring the indication for more aggressive treatment.

Aged↗

Nodal marginal zone B-cell lymphoma resembling plasmacytoma arising from a plasma cell variant of localized Castleman's disease: a case report.

Nodal marginal zone B-cell lymphoma (NMZBL) occasionally represents prominent plasma cell differentiation. Recently, primary lymph node plasmacytoma has been suggested to represent an extremely plasmacytic differentiation of NMZBL. We here report a case of NMZBL showing histological features resembling plasmacytoma arising from a plasma cell variant of localized Castleman's disease (PCLCD). The patient was a 69-year-old Japanese female with a 20-year history of a right inguinal mass. Histologically, a prominent proliferation of plasma cells occupied the interfollicular area of the central portion of the lymph node, whereas centrocyte-like (CCL) cells were the main cellular component in the peripheral portion of the lymph node. Although most of the plasma cells were mature 'Marshalko-type', occasional atypical forms with enlarged nuclei were also present. The majority of the lymphoid follicles had atrophic or regressive germinal centers. A few lymphoid follicles were colonized by CCL cells. Immunohistochemistry study revealed that both plasma cells and some CCL cells had a monotypic intracytoplasmic lambda light chain. When monoclonal plasma cell infiltration is observed in PCLCD, the light chains are mostly restricted to the lambda chain. This case suggests that some plasma cell-containing tumors arising from PCLCD may represent a variant of NMZBL.

Aged↗

Impaired clearance of apoptotic cells induces the activation of autoreactive anti-Sm marginal zone and B-1 B cells.

Since apoptotic cell Ags are thought to be a source of self-Ag in systemic lupus erythematosus, we have examined the role of apoptotic cells in the regulation and activation of B cells specific for Sm, a ribonucleoprotein targeted in human and murine lupus. Using Ig-transgenic mice that have a high frequency of anti-Sm B cells, we find that apoptotic cell injection induces a transient splenic B cell response, while simultaneously causing extensive splenic and peritoneal anti-Sm B cell death. In contrast, mice deficient in the clearance of apoptotic cells develop a chronic anti-Sm response beginning at 1-2 mo of age. These mice have expanded marginal zone and B-1 B cell populations and anti-Sm B cells of both types are activated to form Ab-secreting cells. This activation appears to be Ag-specific, suggesting that activation is due to increased availability of apoptotic cell Ags. Since marginal zone and B-1 cells are positively selected, these data suggest a loss of ignorance rather than a loss of tolerance.

Animals↗