Histopathologic features and expression of Bcl-2 and p53 proteins in primary gastric lymphomas

The aim of this study is to present a histopathologic and immunohistochemical analysis of primary gastric lymphomas which were reclassified according to the concept of mucosa associated lymphoid tissue (MALT). The resected specimens from 41 patients with primary gastric lymphoma were investigated retrospectively. Immunohistochemical study was done to analyze the immunophenotype and bcl-2 and p53 proteins expression. Twenty three of the cases had tumors mainly located in the antrum. Histologically, 12 were low grade and 20 were high grade B-cell lymphoma of MALT, 9 other B-cell nonHodgkin's lymphomas. Helicobacter pylori was identified in 72% of the cases. According to Musshoff's modification, most of the MALT lymphoma cases had stage I or II disease. There was significant difference between low and high grade cases, in respect to depth of invasion in gastric wall. Immunohistochemically, the neoplastic cells in all MALT lymphomas expressed B-cell phenotype. Bcl-2 protein was found to be expressed in 59% and p53 protein expression was detected in 72% of cases. Among the B-cell lymphoma of MALT, bcl-2 positivity decreased and p53 positivity increased significantly as the histological grade advanced. So, an inverse correlation was observed between the expression of bcl-2 and p53. In conclusion, most primary gastric lymphomas are low or high grade B-cell MALT lymphomas and appear to arise in MALT acquired as a reaction to Helicobacter pylori infection. Expression of bcl-2 and p53 in gastric lymphomas may be associated with transformation from low-grade to high-grade disease.     

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.     

Lymphoma of mucosa-associated lymphoid tissue in common variable immunodeficiency

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency characterized by reduced levels of all major immunoglobuline classes and recurrent c infections. The risk of non-Hodgkin's lymphoma (NHL) among patients with CVID was found to be increased in different studies. Mucosa-associated lymphoid tissue (MALT) lymphomas are a recently recognized sub-set of low-grade B-cell NHL composed of marginal zone-related cells. MALT lymphomas appear in the lymphoid tissues as a result of chronic inflammatory or autoimmune stimulation. This study briefly reviews previously published cases and reports a patient suffering from CVID with a history of chronic diarrhea and recurrent sinopulmonary infections. Despite treatment with intravenous immunoglobulin, chronic cough and wheezing progressed. Open lung biopsy showed a MALT lymphoma. Although a rare complication, pulmonary low grade B-cell lymphoma is a diagnosis that must be kept in mind in CVID patients with chronic pulmonary symptoms unresponsive to conventional therapies.     

Primary mucosa-associated lymphoid tissue lymphoma of the breast

Mucosa-associated lymphoid tissue (MALT) lymphoma is an extranodal indolent lymphoma with histopatholigic features similar to those of marginal zone B-cell lymphomas. Primary breast MALT lymphomas were first described by Lamovec and Jancar as a low-grade B-cell lymphoma in 1987. Herein, a case is presented of a patient with primary MALT lymphoma of the breast. Issues in diagnosis and breast-conservation treatment, as it pertains to primary MALT lymphoma of the breast, will be discussed.     

Primary renal mucosa-associated lymphoid tissue ymphoma, the result of chronic pyelonephritis？

Objective： To report 2 cases of primary renal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue （MALT lymphoma）, and observe the relations between this rare tumor of kidney and chronic pyelonephritis. Methods： 2 renal MALT lymphomas were collected from referral consultation. Detailed clinical information were reviewed, morphological analysis based on the HE section, and immunohistochemistry were performed by CD20, CD79a, CD5, CD10, CD43, CD23, BCL10 and Cyclin D1 antibodies. Results： 2 female patients with age of 48 and 55, respectively, all had a history of chronic pyelonephritis. Under the B ultrasonic and CT scanning a bump in the kidney was found. Renal carcinoma suspected and hereby the whole nephrectomy performed. In the macroscopic, tumors were laid in the renal medulla, with dark red color and ill-defined boundary. In the microscopic, there were mixed lymphoid cells infiltrate which mainly consisted of small lympho- cytes, centrocyte-like cells, lymphoplasmacytoid and plasma cells, reactive follicles and lymphoepithelial lesions also could be seen in the lesion, but follicles colonization was rare. In fact, except changes of lymphoma, basic renal disease also could be seen. Most glomeruli were atrophic, some glomeruli were hyperplastic and hypertrophic. Tubules were dilated or contacted, many dilated tubules contained pink-color glassy-appearing casts that suggest the appearance of thyroid tissue. As a result, those 2 cases showed juxtaposed changes of lymphoma and pyelonephritis. Immunohistochemistry showed that tumor cells were CD20 and CD79a positive, CD43 was weak positive, but CD5, CD10, CD23, BCL10 and Cyclin D1 were all negative. Conclusion： Primary renal MALT lymphoma was very rare disease. According to the clinical manifestation, it＇s hard to differentiate from renal cell carcinoma. But the morphological features were consistent with the classic MALT lymphomas in other sites. Immunophenotypic profiles were helpful for diagnosis. Based on the truth that many MALT lymphomas in other sites were connected with chronic inflammations, we suppose that the renal MALT lymphoma may originate from chronic pyelonephritis.     

Clinicopathologic features of Waldenstrom's macroglobulinemia and marginal zone lymphoma: are they distinct or the same entity?

Waldenstrom's macroglobulinemia (WM) is considered in the World Health Organization classification as a clinical syndrome associated with monoclonal immunoglobulin (Ig) M secretion, mainly observed in patients with lymphoplasmacytic lymphoma (LPL) and occasionally with other small B-cell lymphomas. Some authors consider it a rare distinct lymphoproliferative disorder with primary bone marrow infiltration and IgM monoclonal gammopathy. As LPL shares important morphologic and immunophenotypic overlaps with marginal zone B-cell lymphomas (MZLs) in cases showing plasmacytic maturation, it remains unclear if they constitute unique or distinct entities. Both diseases are composed of lymphocytes, lymphoplasmacytoid cells, and tumoral plasma cells with a surface (s) IgM-positive sIgD+/ cytoplasmic IgMpositive CD19+ CD20+ CD27+/ CD5 CD10 CD23 phenotype, without a specific marker. Extranodal mucosa-associated lymphoid tissue (MALT) lymphoma, nodal MZL (NMZL), and splenic MZL (SMZL) are distinct entities displaying common morphologic, immunophenotypic, and genetic characteristics. MALT lymphoma is clearly distinct from LPL, although bone marrow infiltration and IgM paraprotein are not rare. Splenic MZL and NMZL are incompletely characterized, but a plasmacytoid/plasmacytic differentiation, autoimmune manifestations, and monoclonal component are frequent in both diseases. Bone marrow involvement is constant in SMZL and present in 60% of NMZLs. Molecular IgVH gene analysis has confirmed this heterogeneity, particularly within SMZL, with mutated and unmutated cases. Further studies are needed to clarify the pathogenesis of these MZLs and their relationship with LPL.     

肾脏黏膜相关淋巴瘤,是慢性肾孟肾炎的后果吗?

Objective:To report 2 cases of primary renal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT lymphoma), and observe the relations between this rare tumor of kidney and chronic pyelonephritis. Methods: 2renal MALT lymphomas were collected from referral consultation. Detailed clinical information were reviewed, morphological analysis based on the HE section, and immunohistochemistry were performed by CD20, CD79a, CDS, CD10, CD43, CD23,BCL10 and Cyclin D1 antibodies. Results: 2 female patients with age of 48 and 55, respectively, all had a history of chronic pyelonephritis. Under the B ultrasonic and CT scanning a bump in the kidney was found. Renal carcinoma suspected and hereby the whole nephrectomy performed. In the macroscopic, tumors were laid in the renal medulla, with dark red color and ill-defined boundary. In the microscopic, there were mixed lymphoid cells infiltrate which mainly consisted of small lymphocytes, centrocyte-like cells, lymphoplasmacytoid and plasma cells, reactive follicles and lymphoepithelial lesions also could be seen in the lesion, but follicles colonization was rare. In fact, except changes of lymphoma, basic renal disease also could be seen. Most glomeruli were atrophic, some glomeruli were hyperplastic and hypertrophic. Tubules were dilated or contacted, many dilated tubules contained pink-color glassy-appearing casts that suggest the appearance of thyroid tissue.As a result, those 2 cases showed juxtaposed changes of lymphoma and pyelonephritis. Immunohistochemistry showed that tumor cells were CD20 and CD79a positive, CD43 was weak positive, but CD5, CD10, CD23, BCL10 and Cyclin D1 were all negative. Conclusion: Primary renal MALT lymphoma was very rare disease. According to the clinical manifestation, it's hard to differentiate from renal cell carcinoma. But the morphological features were consistent with the classic MALT lymphomas in other sites. Immunophenotypic profiles were helpful for diagnosis. Based on the truth that many MALT lymphomas in other sites were connected with chronic inflammations, we suppose that the renal MALT lymphoma may originate from chronic pyelonephritis.     

CDR3 Sequences of MALT Lymphoma Show Homology with Those of Autoreactive B-Cell Lines

We have examined the CDR3 sequence and adjacent regions of immunoglobulin genes from B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Twenty-nine sequences (15 sequences from 13 low-grade MALT lymphomas, marginal zone B-cell lymphomas; 7 sequences from 6 highgrade MALT lymphomas; 7 sequences from 7 diffuse large cell lymphomas) were obtained after cloning of the polymerase chain reaction-amplified segments. In the low-grade MALT, high-grade MALT and diffuse large cell lymphomas, the mean length of the CDR3 region was 47.6 ± 10.31 (range 21 to 60), 38.71 ± 10.37 (range 27 to 57) and 40.86 ± 3.34 (range 39 to 48) nucleotides, respectively. The length of the CDR3 region was significantly greater in the low-grade MALT lymphoma group than in the other two groups. CDR3 sequences in lymphoma cell clones of 14 cases showed 60 to 81% homology with autoantibody-associated lymphocyte clones including rheumatoid factor. The incidences of these autoantibody-associated lymphocyte clones were higher in the high-grade MALT (4/6) and diffuse large lymphomas (5/7) than in the low-grade MALT lymphoma (5/13). Cases with more than 70% homology at the nucleotide level were found to have 71 to 82% homology with autoantibodies at the protein level in the low-grade MALT lymphomas (2/13), and 67% homology in the high-grade MALT lymphomas (2/7). These results indicate that MALT lymphomas may be derived from the malignant transformation of autoreactive B-cells.     

CDR3 sequences of MALT lymphoma show homology with those of autoreactive B-cell lines.

We have examined the CDR3 sequence and adjacent regions of immunoglobulin genes from B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Twenty-nine sequences (15 sequences from 13 low-grade MALT lymphomas, marginal zone B-cell lymphomas; 7 sequences from 6 high-grade MALT lymphomas; 7 sequences from 7 diffuse large cell lymphomas) were obtained after cloning of the polymerase chain reaction-amplified segments. In the low-grade MALT, high-grade MALT and diffuse large cell lymphomas, the mean length of the CDR3 region was 47.6+/-10.31 (range 21 to 60), 38.71+/-10.37 (range 27 to 57) and 40.86+/-3.34 (range 39 to 48) nucleotides, respectively. The length of the CDR3 region was significantly greater in the low-grade MALT lymphoma group than in the other two groups. CDR3 sequences in lymphoma cell clones of 14 cases showed 60 to 81% homology with autoantibody-associated lymphocyte clones including rheumatoid factor. The incidences of these autoantibody-associated lymphocyte clones were higher in the high-grade MALT (4/6) and diffuse large lymphomas (5/7) than in the low-grade MALT lymphoma (5/13). Cases with more than 70% homology at the nucleotide level were found to have 71 to 82% homology with autoantibodies at the protein level in the low-grade MALT lymphomas (2/13), and 67% homology in the high-grade MALT lymphomas (2/7). These results indicate that MALT lymphomas may be derived from the malignant transformation of autoreactive B-cells.     

CD5 expression in a lymphoma of the mucosa-associated lymphoid tissue (MALT)-type as a marker for early dissemination and aggressive clinical behaviour.

Mucosa associated lymphoid tissue (MALT) developing in response to chronic infection or autoimmune stimuli has been recognized as a possible site of origin for a distinct type of B-cell lymphoma. While preferentially occurring in the stomach, MALT-type lymphomas can be found in virtually all organs. MALT-type lymphomas normally follow an indolent course, with a tendency to remain localized at their site of origin for a prolonged period of time. Histologically, MALT-type lymphomas are heterogeneous covering a cytological spectrum ranging from centrocyte-like cells to smaller lymphoid cells or monocytoid B-cells. Usually a small number of transformed blasts are also present. Immunohistochemically, the malignant cells express markers of B-cell lineage, but are distinct from follicular lymphomas (which express CD10), mantle cell lymphomas (expressing cyclin D1 and CD5) and small lymphocytic lymphoma, which express CD5 and CD23. In contrast to the usual phenotype CD20+CD10-CD5-Cyclin D1-, scattered reports in the literature have documented expression of CD5 in marginal zone B-cell lymphomas of MALT-type. However, these cases are rare, and aberrant CD5-expression has been thought to be a marker for early dissemination and aggressive behavior in some patients, while other reports have also found CD5 expression in localized indolent MALT-type lymphomas. We report a patient with a CD5+ MALT-type lymphoma following an aggressive clinical course without histological progression who relapsed only 18 months after local radiotherapy at the initial localizations (conjunctiva of the right upper eye lid and hypopharynx), and showed a rapid generalization to the contralateral conjunctiva, mediastinal lymph nodes and the esophagogastric junction. Our case lends further support to the notion that CD5+ MALT-lymphomas arising in the head-and-neck area and/or the ocular adnexa might be characterised by an aggressive clinical course.     

Low-grade non-hodgkin lymphomas

The most common low-grade non-Hodgkin lymphomas are of B-cell origin. This review will focus on follicular lymphomas and extranodal marginal zone lymphomas, also known as mucosa-associated lymphoid tissue (MALT) lymphomas. These are radiation-sensitive lymphomas. Moderate doses (30-35 Gy) for these stage I and II low-grade lymphomas result in long-term local control and possible cure. Involved-field radiation therapy is the standard approach and produces minimal morbidity. However, a significant proportion of patients relapse with systemic disease outside of radiation fields. For follicular lymphoma, this occurs in approximately 50% of patients after 15 years and for nongastric MALT lymphoma 30% to 40% after 10 years. Patients with relapsed disease are not curable with chemotherapy, but the disease often remains indolent and prolonged survival is observed. For gastric MALT lymphomas associated with Helicobacter pylori but which did not respond to antibiotic therapy, radiation treatment is indicated and almost always curative. For localized MALT lymphomas not related to microorganisms, radiation therapy is the initial standard therapy regardless of anatomic location. Patients with stage III and IV low-grade lymphoma and local symptoms are often successfully palliated with a low dose regimen of 2 x 2 Gy (total dose 4 Gy).     

Gastric low-grade MALT lymphoma, high-grade MALT lymphoma and diffuse large B cell lymphoma show different frequencies of trisomy.

Gastric MALT lymphoma is a distinct entity related to Helicobacter pylori gastritis. Some studies suggest a role for trisomy 3 in the genesis of these lymphomas, but they mainly focused on low-grade MALT lymphoma. Gastric MALT lymphoma, however, comprises a spectrum from low- to high-grade cases. Furthermore, its exact relation to primary diffuse large B cell lymphoma (DLBCL) of the stomach is not clear. We applied in situ hybridisation (ISH) with centromeric probes on 43 samples of 39 patients with primary gastric lymphoma (13 samples with low-grade MALT lymphoma, 25 with high-grade MALT lymphoma and five with DLBCL) to detect numerical aberrations of 10 chromosomes. ISH was performed immunohistochemically on nuclei isolated from paraffin-embedded resection tissue and on whole paraffin sections using immunofluorescence. In six of 13 low-grade MALT lymphomas trisomy was detected (46%) and mostly involved chromosome 3 (33%). In high-grade MALT lymphomas, trisomies were found in 16 of 25 cases (64%), mainly involving chromosomes 12 and 18. Trisomy 3 was present in only 13% of these cases. Of five DLBCL, only one showed trisomy. Nine of the 16 aberrant high-grade MALT lymphomas (56%) showed trisomy of more than one chromosome per case vs two of six for low-grade cases. In lymphomas with separate low- and high-grade tumour components some trisomies were detected in both components, whereas others occurred only in the high-grade tumour cells. This supports the hypothesis that high-grade MALT lymphomas can develop from a low-grade type and that this progression is accompanied by the acquisition of more genetic aberrations. However, trisomy 3 probably does not play a major role in this progression.     

How to Diagnose and Treat CD5-Positive Lymphomas Involving the Spleen

Patients with CD5-expressing lymphomas presenting with splenomegaly are frequently diagnosed with chronic lymphocytic leukemia. The most important differential diagnosis is mantle cell lymphoma, both in its classical and leukemic, non-nodal forms, given its prognostic and therapeutic implications. Other small B-cell neoplasms that frequently involve the spleen and occasionally express CD5 include the splenic marginal zone lymphoma, hairy cell leukemia and, rarely, lymphoplasmacytic lymphoma. The frequency of CD5 positivity depends in part on the sensitivity of the detection methods employed. Usually, a combination of morphological, immunophenotypic and molecular findings allows for a precise sub-classification of CD5-positive, low-grade B-cell lymphomas of the spleen. Some of these tumors may display a mixture of small and larger B cells, raising the possibility of more aggressive lymphomas, such as diffuse large B-cell lymphomas (DLBCL). Approximately 5–10% of DLBCL are CD5-positive and some may manifest as primary splenic lesions. When available, the morphology of DLBCL in the splenic tissue is distinctive and a leukemic picture is very rare. In conclusion, the appropriate morphological and clinical context assisted by flow cytometry panels and/or immunohistochemistry allows the differential diagnosis of CD5-positive, non-Hodgkin, B-cell lymphomas involving the spleen.     

肾脏黏膜相关淋巴瘤2例报道并文献回顾

背景与目的：原发肾脏的黏膜相关组织淋巴瘤十分罕见,目前世界报道不足50例。本文介绍2例肾脏黏膜相关淋巴瘤的形态学特点和免疫表型特征,旨在使临床和病理对这种低度恶性的B细胞肿瘤的特点有所了解。方法：收集病史资料,形态学评价根据HE切片,用免疫组化法检测肿瘤细胞的表型,使用的抗体包括CD20、CD79、CD5、CD10、CD43、CD23、BCL10和Cyc linD1。结果：2例患者均为女性,年龄分别为48岁和55岁,临床上均有慢性肾盂肾炎病史。B超和CT检查发现肾脏肿块,行全肾切除。大体检查可见肿块位于肾髓质,呈境界不清的暗红色;镜检见肾盂至肾实质弥漫淋巴样细胞浸润,以小淋巴细胞、中心细胞样细胞、淋巴浆细胞和浆细胞浸润为主,可见肿瘤细胞浸润肾小管和肾球囊形成淋巴上皮病变和反应性淋巴滤泡,但没有显著滤泡殖入;免疫组化显示增生细胞以B淋巴细胞为主,散在分布反应性T细胞,肿瘤细胞CD20、CD79 a阳性,CD43弱阳性,CD5、CD10、BCL10、CD23和Cyc linD1均为阴性。结论：原发肾脏黏膜相关淋巴瘤临床极为罕见,临床表现和辅助检查与肾细胞癌不易鉴别,但组织学特点符合经典黏膜相关淋巴瘤的所有特征,免疫表型有助于病理诊断。     

Mucosa-associated lymphoid tissue lymphomas

Mucosa-associated lymphoid tissue (MALT) lymphoma has attracted attention because its concept has amalgamated the study of etiology and pathogenesis in an intriguing group of lymphomas. MALT lymphomas are a B-cell malignancy with characteristic lymphoepithelial lesions; cells are CD20-positive and CD5- and CD10-negative. The molecular changes observed include trisomy 3, t(11;18), and t(1;14) translocations. They commonly occur in the stomach, orbit, salivary glands, and thyroid. Localized disease is present in 60% to 70% of patients. Involvement of multiple extranodal sites has been observed at presentation or during the course of disease. Lymphocyte homing has been implicated in gastrointestinal MALT and may be involved in other MALT lymphomas. Local therapy, either through surgery or radiotherapy, is curative in a high proportion of patients. MALT lymphomas respond to chemotherapy, but there is no evidence that cure can be achieved, although prolonged survival is common. Long-term follow-up is essential for study of the outcomes in this disease.     

Bronchus-associated lymphoid tissue lymphomas: an update of a rare extranodal maltoma

Mucosa-associated lymphoid tissue (MALT) lymphomas were first described by Isaacson and Wright in 1983 in a small series of patients with low-grade B-cell gastrointestinal lymphomas. Although MALT lymphomas occur most frequently in the stomach, they have also been described in various non-gastrointestinal sites, such as the salivary gland, conjunctiva, thyroid, orbit, lung, breast, kidney, skin, liver, uterus, and prostate. The risk of a diagnostic dilemma is reduced by the favorable prognosis of this low-grade lymphoma and its tendency to remain localized to the primary site for a long time. On therapeutic grounds, in contrast to nodal lymphomas, low-grade MALT lymphomas also respond favorably to local treatments, such as surgery and/or local radiation therapy. The outcome and prognosis of low-grade MALT lymphomas are more favorable than those for other extranodal lymphomas. The purpose of this review is to point out the state of the art regarding bronchus-associated lymphoid tissues lymphomas in terms of etiology, pathogenesis, clinics, and therapeutics, including our single-center experience of 23 cases.     

Gastric diffuse large B-cell lymphoma after the diagnosis of primary MALT lymphoma of the breast��One case report

Primary breast and gastric lymphomas as manifestations of primary extranodal lymphomas are rare malignancies, and their diagnosis, prognosis, and treatment modalities remain unclear. We report for the first time the simultaneous co-occurrence of these diseases in one patient. A 60-year-old woman was diagnosed with gastric diffuse large B-cell lymphoma (DLBCL) 2.5 years after she was found to have primary mucosa-associated lymphoid tissue (MALT) lymphoma of the breast. Although the patient underwent chemotherapy, she died of leukemia that caused irreversible cytopenia of three lineages. The data show that her MALT lymphoma apparently transfigured into gastric DLBCL. This case highlights the importance of evaluating patients for Helicobacter pylori infection when they present with extranodal MALT lymphomas, except gastric ones. Positive test findings should prompt anti-H. pylori therapy to prevent MALT lymphomas from transforming into DLBCLs.     

Primary gastric mantle cell lymphoma in a patient with long standing history of Crohn's disease

The stomach is the most common site of primary extranodal lymphoma. Virtually all cases are of B-cell lineage, including extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT lymphoma) and diffuse large B-cell lymphomas. While secondary gastric involvement from nodal mantle cell lymphoma (MCL) or in the course of primary intestinal MCL (lymphomatous polyposis) have been described, primary gastric MCL has not been reported so far. A 74-year-old man with a 14 year-history of Crohn's disease was admitted at a general hospital due to epigastric pain refractory to therapy with proton-pump inhibitors. Endoscopy disclosed a large polypoid tumor with an ulcerated surface at the greater curvature of the gastric antrum. Endosonography demonstrated the tumor to be limited to the stomach with only local lymph node involvement. Histology of gastric biopsies revealed a dense atypical lymphoid infiltrate composed of small to medium sized cells with slightly irregular nuclear contours. Immunohistochemichally, the cells were positive for CD20, CD79a, CD43 and cyclin D1, but negative for CD3, CD5 and bcl-6. They stained for IgM and showed lambda-light chain restriction. Fluorescent in situ hybridisation studies showed the presence of the t(11;14) characteristic for MCL. No further evidence of lymphoma was found on extensive clinical staging. Following chemotherapy the patient is disease free at 24 months after diagnosis. This is the first case of a primary localized gastric MCL. The lack of CD5 expression underscores the importance of performing thorough immunohistochemical studies, particularly to exclude MALT lymphoma.     

Chromosome instability and translocation t(11;18) in primary gastric marginal zone B-cell lymphoma of MALT-type

The prognosis for patients with mucosa-associated lymphoid tissue (MALT) lymphomas is good; these tumours have usually an indolent course with overall survival rates that are greater than 80% at 5-year, but some rare cases with histological transformation in aggressive diffuse large cell lymphoma have also been diagnosed. Here, we present cytogenetic results on endoscopic bioptic material of 42 cases of primary gastric extranodal marginal zone B-cell lymphoma (EMZL) using fluorescence in situ hybridization (FISH) approach with API2, MALT1 and centromeric probes for chromosome 3 and 18, and their impact on the clinical outcome.