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PubMed2025

Exploring the Genetic Landscape of Primary Marginal Zone Lymphoma of the Urinary Bladder.

Extranodal marginal zone B-cell lymphoma (MZL) of mucosa-associated lymphoid tissue is the most frequent primary lymphoma of the urinary bladder. Although MZLs from various anatomical sites are often associated with autoimmune disorders, infections, and site-characteristic genetic alterations, the molecular foundations and potential infectious triggers of urinary bladder MZL remain poorly understood. To elucidate the disease etiology and correlation with MZLs arising in other locations, we examined a cohort of 17 cases (11 women and 6 men) diagnosed with primary bladder MZL between 2005 and 2025. Immunohistochemical analysis confirmed the literature, with all samples testing positive for the pan B-cell markers CD20 and CD79a and negative for CD5 (except 1), cyclin D1, and SOX11. Thirteen samples exhibited secretory differentiation and displayed immunoglobulin light chain restriction (9 κ and 4 λ). No gene rearrangements in BCL2, BCL6, BCL10, IRF4, MALT1, and MYC were detected. High-throughput sequencing identified 31 pathogenic/likely pathogenic somatic mutations across 18 genes, with TBL1XR1 (n = 8), MAP2K1 (n = 4), and TNFAIP3 (n = 2) being the most frequently mutated ones. Additionally, all cases included variants of unknown significance. The sample of 1 patient tested positive for Chlamydia trachomatis, human betaherpesvirus 6B, and Epstein-Barr virus. Escherichia coli was detected in 5 samples. We provide compelling evidence that urinary bladder MZL is a point mutation-driven disease rather than gene fusion-driven disease and that E coli is present in approximately one-third of tumor biopsies. These tumors frequently harbor pathogenic mutations in genes encoding components regulating plasma cell differentiation and the pleiotropic MAPK/ERK signaling pathway. TBL1XR1, which was unexpectedly frequently mutated, is generally linked to more aggressive variants of MZL and diffuse large B-cell lymphoma; however, its prognostic significance in urinary bladder MZL remains to be determined. Comparative analysis highlighted partial overlap of urinary bladder MZL mutational profiles with those found in salivary gland MZL.

Humans↗
PubMed2026

Diversified cell origin of Helicobacter pylori eradication-responsive gastric diffuse large B-cell lymphomas.

A significant proportion of gastric diffuse large B-cell lymphoma with mucosa-associated lymphoid tissue [DLBCL(MALT)] and without MALT ('pure' DLBCL) can be resolved by Helicobacter pylori eradication (HPE). Gastric MALT lymphoma is an indolent lymphoma derived from memory B cells in the marginal zone. In the present study, we aimed to explore the origin of large cells in HPE-responsive gastric DLBCLs (complete remission after HPE). We investigated gastric lymphoma biopsies from 31 patients with HPE-responsive DLBCLs [15 'pure' DLBCLs, 16 DLBCL(MALT)s]. We used the Hans algorithm (CD10, BCL-6, and MUM1) to define the origins of germinal center B cell (GCB) and non-GCB. To further ascertain the cellular origin, 11 'pure' DLBCLs were examined using an Agilent whole-human genome microarray. Eleven DLBCLs [eight with 'pure' DLBCL and three with DLBCL(MALT)] were also assessed using Lymph2Cx. Specific GCB markers, including BACH2, AID, and BCL2 rearrangement and enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) codon 641 mutations, were evaluated in 31 patients with HPE-responsive gastric DLBCLs. According to the Hans algorithm, 53% (8/15) of gastric 'pure' DLBCLs and 50% (8/16) of DLBCL(MALT)s were of the GCB phenotype. Gene expression assays revealed that five of six patients with 'Hans' GCB had GCB genetic signatures, whereas four of five patients with 'Hans' non-GCB had activated B-cell genetic signatures. The Lymph2Cx assay revealed the GCB subtype in seven of eight patients with 'Hans' GCB. The expression patterns of BACH2 (p = 0.005) and AID (p = 0.038) closely correlated with the 'Hans' GCB phenotype. BCL2 rearrangements and EZH2 codon 641 mutations were detected in 44% (7/16) and 13% (2/16) of patients with 'Hans' GCB, respectively. In another cohort of 29 HPE-unresponsive gastric DLBCLs [19 'pure' DLBCLs and 10 DLBCL(MALT)s], we found a close association between the 'Hans' GCB subtype and the GCB subtype as determined by the Agilent whole-human genome microarray and Lymph2Cx in lymphoma cells of these patients. In conclusion, more than half of HPE-responsive large cell lymphoma cases in the stomach were of GCB origin. © 2026 The Pathological Society of Great Britain and Ireland.

Humans↗
PubMed1988

Monocytoid B-cell lymphoma, a tumour related to the marginal zone.

Monocytoid B-lymphocytes are a B-cell subset present in subcapsular sinuses in some cases of lymphadenitis. We describe a case of lymphoma of this cell type. The tumour shows a distinctive morphology characterized by concentric strands of tumour cells around lymphoid follicles with hyperplastic germinal centres and conserved mantle zones. Electron microscopy of these cells shows short cellular processes as well as moderate development of endoplasmic reticulum. The phenotype of the tumour was monoclonal IgM-kappa, distinct from other node-based B-cell subpopulations and suggesting a possible relationship to the lymphocytes of the marginal zone present peripheral to lymphoid follicles of the spleen. Morphological features that suggest a relationship with hairy cell leukaemia are contrasted by phenotypic differences and the ultrastructural absence of ribosomic lamellar complexes.

Aged↗
PubMed1992

Splenic marginal zone cell lymphoma.

We describe four female patients with primary splenic low-grade non-Hodgkin's B-cell lymphomas with the morphology and immunophenotype of splenic marginal zone lymphocytes. The patients presented with splenomegaly, anemia, and weight loss. The bone marrow was involved in all four cases. Liver involvement was found in one patient; and in another, a CT scan revealed lymphadenopathy in the chest and abdomen. The histology of the spleen was characterized by broad concentric strands of monomorphic medium-sized lymphocytes around lymphoid follicles in one case and infiltrating follicles in two cases. Selective replacement of follicles was seen in one case. Tumor in splenic hilar lymph nodes (four cases) and liver (one case) was similar. Three patients remain well 4, 9, and 12 months, respectively, after splenectomy without further treatment. One patient who received chemotherapy died 1 year after splenectomy.

Adult↗
PubMed1988

B lymphocytic lymphoma (large cell) of possible splenic marginal zone origin presenting with prominent splenomegaly and unusual cordal red pulp distribution.

Two cases of large cell lymphoma, B-cell type, primarily involving the red pulp of the spleen rather than the white pulp are described. A number of unusual features suggest that this may be a lymphoma originating from a distinct splenic B-cell lymphocyte whose origin may be the marginal zone of the spleen or the splenic cords. The patients presented with splenomegaly, cytopenias, and no peripheral lymphadenopathy. The gross appearance of the spleens was beefy red without tumor nodules. The tumor cells were primarily in the splenic cords and surrounding residual normal white pulp. There was a minimal hemic phase. The tumor cells had abundant cytoplasm, surface IgM, IgD, kappa, and FC receptors, tartrate-resistant acid phosphatase, but no alkaline phosphatase or interleukin-2 receptors. They had a similar DNA aneuploidy. The most unusual feature was that tumor cells in both cases had phagocytic properties. These lymphomas may be clinically more indolent than their follicular center counterparts.

Adult↗
PubMed1990

[Low-grade B cell gastric lymphoma originated in mucosa-associated lymphoid tissue. Relationship of tumor cells with the marginal zone and monocytoid B lymphocytes. An immunohistochemical and ultrastructural study].

Seven cases of gastric B-cell low-grade lymphomas were characterized by morphology, immunohistology and electron microscopy. All them were immunophenotyped with a panel of monoclonal antibodies against immunoglobulins and other B-cell determinants. Histologic study of gastric B-cell low-grade lymphomas showed germinal centers of lobated shape and polyclonal nature, mainly polyclonal subepithelial plasma cell (except in one case) and neoplastic interfollicular B-cells of monoclonal character. Light-chain restriction supports the neoplastic nature of gastric lymphoma of low-grade malignancy, a distinctive tumour of extranodal B-cell origin. Interfollicular B-cells share with marginal zone cells a perifollicular localization, morphology and phenotype, suggesting a possible relation between these two cellular subtypes. In two cases, the tumour appears constituted by monocytoid B-lymphocytes (MBL), which suggests a relation of tumoral interfollicular B-cells with this subpopulation.

Adult↗
PubMed1990

[The morphological diagnosis of malignant non-Hodgkin's lymphomas (lymphosarcomas)].

On the basis of morphoimmunological correlates certain criteria have been elaborated helpful in diagnosis of non-Hodgkin's malignant lymphomas (NML) of both B- and T-cell origin, and this was reflected in the modified Kiel's classification. The group of T-cell NML has considerably increased. T-cell origin of Lennert's lymphoma and angioimmunoblastic lymphadenopathy has been proven. Morphological substrate of NML from peripheral T-lymphocytes became more precise. The tumours, depending on the predominant cells, are subdivided into small cell (T-zones and pleomorphic lymphoma of small cells), mixed cell (pleomorphic lymphoma of medium-size and large cells) and large cell lymphoma (immunoblastic and large cell anaplastic Ki-I+). Criticism of T-NML systematization is due to the lack of definite cytological criteria because of the extreme morphological heterogeneity of peripheral T-lymphocytes and different interpretation of the clinical course of the established morphological variants. Among B-cell lymphomas the problem of the so-called intermediate lymphocytic lymphoma (ILL) and its variety--a mantle-zone lymphoma as well as monocytoid B-cell lymphoma is discussed in the literature. It is established in immunological testing that the cells of ILL possess a phenotype of cells of the primary follicles and those of the mantle-zone of the secondary follicles while the cells of the monocytoid B-cell NML have a peculiar unique phenotype similar to that of cells in the marginal zone of the spleen follicles.

Humans↗
PubMed1991

Monocytoid B-cell lymphoma: morphological variants and relationship to low-grade B-cell lymphoma of the mucosa-associated lymphoid tissue.

Twenty-eight cases of monocytoid B-cell lymphoma of lymph nodes and 16 lymph node metastases of primary gastric lymphomas, mostly low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) type were investigated morphologically and immunohistochemically. Both groups showed the same morphological and immunohistochemical features: diagnostically important sites of infiltration were the sinuses and the marginal zones. The tumour cells were either medium-sized or small. The cytoplasm stained grey with Giemsa and was sometimes rather pale. In imprints the grey colour of the cytoplasm was a characteristic feature. The medium-sized cell type was more frequent; in one third of the cases it was combined with a prominent lymphoplasmacytic component from the same clone, and it resembled the monocytoid B-cells of the sinuses. The small cell type was less common, was not combined with a lymphoplasmacytic component and more closely resembled marginal zone cells. The difference was underlined by the negative reaction with the monoclonal antibody Ki-B3 in the small cell type, which, conversely, was positive in the medium-sized cell type and in the monocytoid B-cell reaction of the sinuses. Both of these cell types, however, showed a granular reaction with the new monoclonal antibody Ki-Mlp. The morphological and immunohistochemical parallels are arguments in favour of the assumption that monocytoid B-cell lymphoma is the nodal equivalent of low-grade B-cell lymphoma of MALT type. This is further supported by the fact that in nine of our 28 cases of monocytoid B-cell lymphoma, lymphomas were found simultaneously or subsequently in organs of the MALT. Monocytoid B-cell lymphoma must be differentiated from an infiltration that occurs in the form of clusters of monocytoid B-cells in other low-grade B-cell lymphomas, especially in immunocytoma with a high content of epithelioid cells.

Adult↗
PubMed1988

CD1c antigens are present in normal and neoplastic B-cells.

The immunohistochemical detection of CD1c antigen is described in mantle zone B-cells of the tonsil, lymph node, and spleen, and also in the marginal zone B-cells of the spleen. CD1c expression was observed in most cases of low-grade, but in only a single case of high-grade, B-cell non-Hodgkin's lymphoma. It was not detected in germinal centre cells, nor in Epstein-Barr virus-transformed or Burkitt's lymphoma B-cell lines. This distribution suggests that CD1c expression may occur preferentially in slowly proliferating B-cell populations and does not support previous suggestions that CD1c is a human equivalent of the mouse thymus leukaemia antigens.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1992

Splenic involvement by aggressive malignant lymphomas of B-cell and T-cell types. A morphologic and immunophenotypic study.

To determine whether there are any consistent morphologic differences between B-cell and T-cell aggressive non-Hodgkin's lymphomas of the spleen, the authors analyzed 16 spleens involved by mixed cell (1 case) or large cell (15 cases) lymphomas. Immunologic data were derived from cell suspensions or frozen tissue in each case. Five cases had a T-cell phenotype, and 11 were B-cell. Morphologic features favoring a T-cell phenotype included epithelioid histiocytic reactions, confinement of the lymphomas to the splenic T-zones (periarteriolar lymphoid sheath and marginal zone), and clear cell or polymorphous cytologic features. Features favoring a B-cell phenotype included multiple discrete nodules in the white pulp, large coalescent tumor nodules in association with small lymphocytic lymphoma, and large non-cleaved or immunoblastic plasmacytoid cytologic characteristics. Four cases were unusual because most neoplastic large cells were distributed diffusely or formed only small aggregates in the red pulp without definite tumor masses or nodules involving the white pulp. Because of this distribution and the frequently encountered erythrophagocytosis by benign-appearing histiocytes, these cases resembled malignant histiocytosis. A T-cell phenotype was predicted for all four cases; however, only one case, a lymphoma with polymorphous cytologic characteristics, was of T-cell lineage. The other three cases were of B-cell lineage. The authors' results indicate that in most instances the B-cell or T-cell nature of aggressive splenic lymphomas is predictable from the distributional and cytologic features. As in lymph nodes, there are cases for which the morphologic characteristics of B-cell and T-cell lymphomas are indistinguishable.

Adult↗
PubMed1987

Primary B-cell gastric lymphoma--a reassessment of its histogenesis.

Primary gastric lymphoma, (PGL), is thought to be a tumour of follicle centre cell origin containing centrocyte-like (CCL) cells, and plasma cell components. The advent of novel leucocyte antibodies reactive in paraffin sections and improved techniques for the demonstration of immunoglobulin (Ig) in tissues has permitted a reassessment of the histogenesis of PGL. Our results have shown that PGL is a tumour of CCL cells with plasma cell differentiation in a minority of cases. Follicles were reactive, as defined by polytypic expression of Ig, in each case but selective invasion of reactive follicles by neoplastic CCL cells often led to a misleading appearance of malignancy. CCL cells bear close similarities to marginal zone cells which have been defined as a distinct non-circulating B-cell lineage. This could account for the favourable clinical behaviour of PGL.

B-Lymphocytes↗
PubMed1992

[Digestive lymphomatous polyposis].

We report 7 prospectively followed cases of lymphomatous polyposis of the gastrointestinal tract. They were characterized by multiple polypoid lesions affecting several segments of the gastrointestinal tract always involving the colon and the rectum. An ileocecal mass was present in 4 cases. Regional lymph node involvement was constant. Peripheral lymphadenopathy was frequent (5 cases out of 7), as was other extra-digestive extension to the bone marrow (4 cases out of 7) and cavum (3 cases out of 7). The histopathological aspect was that of a small cleaved cells (working formulation) or centrocytic (Kiel classification) non-Hodgkin's lymphoma. The peculiar morphology and phenotype of the tumoral B-lymphocytes suggest their possible follicle marginal zone origin. Lymphomatous polyposis bore a rapidly fatal prognosis in every case (mean survival 20 months). This study of seven patients together with the 20 well-documented cases of the literature confirms the existence of lymphomatous polyposis as a distinctive clinicopathological entity among gastrointestinal non-Hodgkin's lymphoma.

Adult↗
PubMed1991

Follicular colonization in B-cell lymphoma of mucosa-associated lymphoid tissue.

The formation of neoplastic B-cell follicles is universally accepted as diagnostic of a follicle centre cell (FCC) lymphoma. Low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) are characterized by a diffuse infiltrate of cells of uncertain lineage known as "centrocyte-like" cells because of their resemblance to centrocytes (small cleaved cells). Some MALT lymphomas, however, contain numerous follicles and may even have a predominantly follicular appearance. These follicles may be reactive or show immunoglobulin (Ig) light-chain restriction, indicating their neoplastic nature. We have proposed that these neoplastic follicles are not composed of follicle centre cells but result from colonization of reactive follicles by CCL cells. In this study, the immunophenotype and genotype of 10 primary gastrointestinal lymphomas with a follicular component have been determined. One case exhibited the morphological, immunophenotypic, and genotypic features of FCC lymphoma (Ig light-chain restriction, CD10+, KB61 (CDw32)-, Jh, and bcl-2 gene rearrangement). Neoplastic follicles in the remaining nine cases, which showed the features of MALT lymphoma, were of a different phenotype (Ig light-chain restriction, CD10- KB61(CDw32)+), and these lymphomas showed Jh but not bcl-2 gene rearrangement. Taken in conjunction with the morphological features, these findings suggest that in these cases the neoplastic follicles formed as the result of colonization of previously reactive follicles by neoplastic CCL cells. Thus, not all lymphomas containing neoplastic follicles are of FCC origin. Follicular colonization, as seen in low-grade MALT lymphomas, is likely to be a recapitulation of an as yet undescribed normal immunological phenomenon that may involve marginal zone B cells.

Gene Rearrangement↗
PubMed1990

A study of the properties of a low-grade mucosal B-cell lymphoma using a monoclonal antibody specific for the tumour immunoglobulin.

Primary low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) are tumours with distinctive clinico-pathological characteristics, two of which are studied in this paper, namely the tendency of the tumours to remain localized and the morphologic and phenotypic resemblance of the malignant cells to splenic marginal zone B cells. We have made a detailed study of a small intestinal lymphoma and a gastric lymphoma, which together with the spleen were resected from the same patient. Using a monoclonal antibody (7G3) raised against a unique determinant on the small intestinal tumour, we were able to detect disseminated small intestinal tumour cells in the stomach and spleen. The tumour in the stomach was genetically related, but non-identical to that in the small intestine, and was not recognized by 7G3. Lymphocytes expressing the marker of the small intestinal tumour (7G3) were present in lymphoid nodules in the stomach, and 7G3+ plasma cells were present beneath the gastric epithelium. In the spleen, cells expressing 7G3 were present in the marginal zone and plasma cells expressing the same marker were present in the red pulp. These findings suggest that low-grade MALT lymphomas may migrate beyond the primary tumour site, but that tumour cells distant to the primary site may differentiate into mature, non-dividing plasma cells. The localization of small intestinal tumour cells in the splenic marginal zones reinforces the suggestion of lineage homology between these populations of cells.

Antibodies, Monoclonal↗
PubMed1988

Primary B-cell lymphoma of salivary glands and its relationship to myoepithelial sialadenitis.

A detailed morphologic and immunohistochemical study has been carried out on salivary glands excised from 20 cases in which the initial histologic diagnosis was either myoepithelial sialadenitis (MESA) or salivary gland lymphoma (SGL). The results have shown that these cases, except one that had been diagnosed as MESA, showed a spectrum of changes ranging from focal lymphoid infiltrates, designated as early MESA, through established MESA with dense, extensive lymphoid infiltration, to lymphoma. The distribution of the lymphoid infiltrate in early MESA was related to ducts and mimicked Peyers patches. In established MESA, this infiltrate became confluent with the formation of prominent epimyoepithelial islands. The evolution of lymphoma was characterized by an expanded population of centrocyte-like (CCL) cells that showed light chain restriction. Like other lymphomas of mucosa-associated lymphoid tissue, to which they bear a striking resemblance, salivary gland lymphomas may remain localized for prolonged periods with a tendency to local recurrence rather than to distant spread. These properties may be explained by the histogenesis of these tumors from CCL cells that appear to be of similar lineage of splenic marginal zone cells.

Adult↗
PubMed1981

Receptors for Helix pomatia agglutinin on normal and neoplastic lymphocytes -- a histochemical study using paraffin embedded tissue sections.

In order to investigate the distribution and significance of receptors for Helix pomatia agglutinin (HPA), paraffin sections from several reactive and 70 neoplastic lymphoid tissues were utilized for a histochemical study after neuraminidase treatment. Lymphocytes in the germinal center and thymic cortex were mostly negative for the receptors, while most of the lymphocytes in the thymus-dependent area, some of those in the primary follicle or in the marginal zone and most of the plasma cells in the medulla possessed the receptors on their surfaces. Nodular lymphomas, thymomas, and diffuse lymphoblastic lymphomas were mostly negative in contrast to the positive reaction in diffuse poorly differentiated lymphomas of B-cell type and plasmocytomas. Diffuse histiocytic lymphomas and diffuse mixed lymphocytic and histiocytic lymphomas occasionally possessed the receptors, irrespective of their immunological markers. Hodgkin's cells were negative on their surface, but were occasionally positive in their cytoplasms ans seen in case of histiocytes. From these results, HPA receptors could be neither T-cell nor B-cell differentiation marker. The possibility that HPA-receptor-negative lymphocytes may hav a quick turn-over rate or a short life span is also discussed.

Adult↗
PubMed1990

Low grade B cell lymphoma of gut-associated lymphoid tissue (GALT): a model of the structure and migration pathways of the B cell component of normal human GALT.

The histology, microenvironment and migratory pathways of low grade B cell lymphomas (LGBL) are thought to reflect those of normal lymphoid tissue of similar lineage. Striking clinical differences between LGBL of peripheral lymph nodes and those of the gastrointestinal tract serve to emphasize the lineage differences between mucosal and non-mucosal B cells and suggest that LGBL of gut-associated lymphoid tissue (GALT) could serve as a natural experimental model for the investigation of the properties of normal human GALT. The histology of LGBL of GALT parallels that of normal GALT and draws particular attention to the previously undescribed GALT marginal zone B cells which show close lineage homology with LGBL of GALT. These cells known as centrocyte-like (CCL) cells surround follicles, infiltrate the epithelium and frequently show plasma cell differentiation possibly in response to stimulation from the gut lumen. In LGBL of GALT the CCL cells have an intimate relationship with reactive follicles similar to that described for rat splenic marginal zone cells. LGBL of GALT are slow to disseminate to the periphery and can often be cured by local eradication. This suggests CCL cells do not enter the peripheral blood. However, the gastrointestinal tract remote from the primary tumour is occasionally selectively involved, a finding which supports circulation and homing as described in animals. Using a murine monoclonal anti-idiotypic antibody in one case of LGBL of GALT we have shown that CCL cells appear to enter the circulation and, in the absence of evident tumour, can be identified in the mucosae as well as the marginal zone of the spleen where they undergo plasma cell differentiation.(ABSTRACT TRUNCATED AT 250 WORDS)

B-Lymphocytes↗
PubMed1980

Immunohistologic analysis of the organization of normal lymphoid tissue and non-Hodgkin's lymphomas.

Hoping to improve the systems for identifying and classifying normal and malignant lymphoid subpopulations, frozen and paraffin sections of nonmalignant lymphoid tissue and of malignant lymphomas were immunostained for surface (S) and cytoplasmic antigens using the peroxidase-antiperoxidase method. Primary follicle cells and follicle mantle cells known to be part of the recirculating B-cell pool were found to be constantly Ia and C3 receptor (C3R) positive, mostly SIgM and SIgD positive and cytoplasmic immunoglobulin (CIg) negative. The light zone of germinal centers (GC), which is rich in centrocytes, contained a large number of T cells and showed the well-known intercellular Ig network pattern; the dark zone, containing densely packed centroblasts, was usually free of T cells, but was bordered ay a mantle-like accumulation of T cells. Usually only some of the GC cells were definitely positive for SIg and CIg of different classes. All cells reacted positively for Ia and C3R. In areas described by other authors as containing marginal zone cells, cells densely bearing SIgM and deficient in SIgD were detected. The immunoblasts of the hyperplastic plasma cell reaction usually contained CIg. Cells from chronic lymphoid leukemia sections that immunostained for SIgM and SIgD were interpreted as representing a neoplasm of recirculating B cells expressing SIgM and SIgD. The immunohistologic architecture of follicular centroblastic/centrocytic lymphoma showed a more or less close similarity to the organization of secondary follicles. Lymphomas whose cells resembled reactive centrocytes were strongly SIgM positive and SIgD negative or only weakly SIgD positive. CIg was demonstrable in nearly 90% of the lymphomas whose cells resembled centroblasts and in 70% of the lymphomas whose cells resembled immunoblasts of the plasma cell reaction. Finally, immunohistologic staining results from a T-zone lymphoma are presented, which confirm that this lymphoma was composed of a neoplastic T zone and a non-malignant B zone.

Antigens↗