[Clinical Impact Assessment and Utilization Prospects of the t(11:18) Chromosomal Translocation in Gastric MALT Lymphoma in Koreans: A Single Center Retrospective Analysis].

Background/Aims: The gastric extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (gastric MALT lymphoma) are mostly related to Helicobacter pylori infections. However, chromosomal aberration involving translocation t(11;18) is also frequently reported in these patients. Methods: The study was a retrospective review and analysis of electronic medical records to assess the factors which affect complete remission (CR) in patients with gastric MALT lymphoma. Based on the medical records, subjects with gastric MALT lymphoma were enrolled consecutively from January 2004 to December 2021. Results: Among the 77 subjects who were found with gastric MALT lymphoma in the database, 65 cases with complete records were analyzed. Of these, 66.2% (43/65) were H. pylori positive. Genetic analyses for t(11:18) were done on 41 subjects. The t(11:18) chromosomal translocation with MALT1:BIRC3 fusion was found in 31.7% (13/41) of the subjects. With H. pylori eradication therapy, 75% (21/28) of the subjects without t(11:18) achieved CR. However, only 23.1% (3/13) subjects with t(11:18) could achieve CR (p-value= 0.009). In the H. pylori-positive group, 85.7% (18/21) subjects without t(11:18) achieved CR with eradication therapy, but 71.4% (5/7) subjects with t(11:18) failed to achieve CR (p-value=0.004). In the H. pylori-negative group, 42.3% (3/7) of the subjects without t(11:18) achieved CR with eradication therapy. However, 83.3% (5/6) of H. pylori-negative subjects with t(11:18) failed to achieve CR with eradication therapy and needed additional radiotherapy (p-value=0.396). Conclusions: H. pylori negativity and the presence of t(11:18) were both risk factors for failure to achieve CR with H. pylori eradication therapy as the first line of treatment.

Targeted massively parallel sequencing of mature lymphoid neoplasms: assessment of empirical application and diagnostic utility in routine clinical practice.

Massively parallel sequencing (MPS) has become a viable diagnostic tool to interrogate genetic profiles of numerous tumors but has yet to be routinely adopted in the setting of lymphoma. Here, we report the empirical application of a targeted 40-gene panel developed for use in mature lymphoid neoplasms (MLNs) and report our experience on over 500 cases submitted for MPS during the first year of its clinical use. MPS was applied to both fresh and fixed specimens. The most frequent diagnoses were diffuse large B-cell lymphoma (116), chronic lymphocytic leukemia/small lymphocytic lymphoma (60), marginal zone lymphoma (52), and follicular lymphoma (43), followed by a spectrum of mature T-cell neoplasms (40). Of 534 cases submitted, 471 generated reportable results in MLNs, with disease-associated variants (DAVs) detected in 241 cases (51.2%). The most frequent DAVs affected TP53 (30%), CREBBP (14%), MYD88 (14%), TNFRSF14 (10%), TNFAIP3 (10%), B2M (7%), and NOTCH2 (7%). The bulk of our findings confirm what is reported in the scientific literature. While a substantial majority of mutations did not directly impact diagnosis, MPS results were utilized to either change, refine, or facilitate the final diagnosis in ~10.8% of cases with DAVs and 5.5% of cases overall. In addition, we identified preanalytic variables that significantly affect assay performance highlighting items for specimen triage. We demonstrate the technical viability and utility of the judicious use of a targeted MPS panel that may help to establish general guidelines for specimen selection and diagnostic application in MLNs in routine clinical practice.

Evaluating breast lymphoplasmacytic infiltrates: a multiparameter immunohistochemical study, including assessment of IgG4.

Lymphoplasmacytic infiltrates in the breast, a modified skin appendage, include lymphocytic lobulitis, other nonspecific benign proliferations, and mucosa-associated lymphoid tissue (MALT)-type lymphoma. Distinguishing these entities, all of which may be B-cell rich and may have associated sclerosis, can be difficult. In addition, the proportion that represents IgG4-related disease is unknown, and the similarity of MALT lymphomas to primary cutaneous marginal zone lymphoma is uncertain. To address these questions, the clinical, histologic, and immunohistochemical features of 50 benign and malignant breast lymphoplasmacytic infiltrates (10 lymphocytic lobulitis, 1 granulomatous, 19 not otherwise specified, 20 MALT lymphomas) were evaluated. Compared with the MALT lymphomas, benign cases had a less dense infiltrate (P < .001), fewer but more histologically apparent germinal centers (P < .001), and more marked fibrosis (P < .0001). Greater than 60% B cells were present in 23% (7/30) benign cases versus 75% (15/20) MALT lymphomas (P = .0003). Plasma cells were predominantly IgG+ in 83% (24/29) benign cases and predominantly IgM+ in 73% (14/19) MALT lymphomas (P < .0001). None of the benign cases had greater than 50 IgG4+ plasma cells/high-power field, and only 1 lymphocytic lobulitis case had an IgG4/IgG ratio exceeding 40% and no clinical evidence for extramammary IgG4-related disease. Although there may be some overlapping features, routine histopathology together with limited immunohistochemical stains can distinguish benign from neoplastic lymphoplasmacytic infiltrates in the breast. Despite frequent sclerosis, the breast is not a common site of unrecognized IgG4-related sclerosing disease. Although there are similarities, breast MALT lymphomas can be separated from cutaneous marginal zone lymphoma.

CD200 flow cytometric assessment and semiquantitative immunohistochemical staining distinguishes hairy cell leukemia from hairy cell leukemia-variant and other B-cell lymphoproliferative disorders.

OBJECTIVES: To evaluate CD200 expression in B-cell proliferative disorders. METHODS: We analyzed 180 recent specimens of B-cell neoplasms for CD200 expression by flow cytometric immunophenotypic analysis, which is better able to assess relative intensity of staining than immunohistochemical staining. RESULTS: We found that hairy cell leukemia exhibits a high level of staining for CD200 in comparison to other B-cell lymphoproliferative disorders, including hairy cell leukemia-variant (HCL-V), marginal zone lymphoma, and lymphoplasmacytic lymphoma. We confirmed this observation by semiquantitative immunohistochemical staining. CONCLUSIONS: Assessment of the CD200 expression level is helpful to distinguish HCL from HCL-V and other B-cell lymphoproliferative disorders and in the differential diagnosis of B-cell neoplasms in general.

Immunoglobulin heavy-chain fluorescence in situ hybridization-chromogenic in situ hybridization DNA probe split signal in the clonality assessment of lymphoproliferative processes on cytological samples.

BACKGROUND: The human immunoglobulin heavy-chain (IGH) locus at chromosome 14q32 is frequently involved in different translocations of non-Hodgkin lymphoma (NHL), and the detection of any breakage involving the IGH locus should identify a B-cell NHL. The split-signal IGH fluorescence in situ hybridization-chromogenic in situ hybridization (FISH-CISH) DNA probe is a mixture of 2 fluorochrome-labeled DNAs: a green one that binds the telomeric segment and a red one that binds the centromeric segment, both on the IGH breakpoint. In the current study, the authors tested the capability of the IGH FISH-CISH DNA probe to detect IGH translocations and diagnose B-cell lymphoproliferative processes on cytological samples. METHODS: Fifty cytological specimens from cases of lymphoproliferative processes were tested using the split-signal IGH FISH-CISH DNA probe and the results were compared with light-chain assessment by flow cytometry (FC), IGH status was tested by polymerase chain reaction (PCR), and clinicohistological data. RESULTS: The signal score produced comparable results on FISH and CISH analysis and detected 29 positive, 15 negative, and 6 inadequate cases; there were 29 true-positive cases (66%), 9 true-negative cases (20%), 6 false-negative cases (14%), and no false-positive cases (0%). Comparing the sensitivity of the IGH FISH-CISH DNA split probe with FC and PCR, the highest sensitivity was obtained by FC, followed by FISH-CISH and PCR. CONCLUSIONS: The split-signal IGH FISH-CISH DNA probe is effective in detecting any translocation involving the IGH locus. This probe can be used on different samples from different B-cell lymphoproliferative processes, although it is not useful for classifying specific entities. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Assessment of the prognostic indices IPI and FLIPI in patients with mucosa-associated lymphoid tissue lymphoma.

BACKGROUND: The prognostic values of the International Prognostic Index (IPI) and the Follicular Lymphoma International Prognostic Index (FLIPI) have widely been demonstrated in diffuse large B-cell lymphoma and follicular lymphoma. No attempts to assess their applicability in MALT lymphoma have been made so far. PATIENTS AND METHODS: A total of 143 patients with MALT-lymphoma were analysed. Parameters of both IPI and FLIPI were retrospectively assessed and correlated with relapse and time to relapse as markers of clinical course. RESULTS: According to IPI, 96 patients (67%) were classified as low, 22 (15%) low-intermediate, 17 (12%) high-intermediate and 8 (6%) as high risk. FLIPI identified 99 patients (70%) at low risk, 35 (24%) at intermediate and 9 (6%) at high risk. After a median follow-up time of 39.5 months, 123 patients were alive and 46 patients had relapsed (median time to relapse 27 months). IPI significantly correlated with time to relapse, with the typical differentiation into low, low-intermediate and high risk groups. FLIPI divided patients into three groups, but the low and intermediate risk groups showed a similar clinical course. In terms of additional progonostic factors, univariate analysis suggested autoimmune disease and multifocal disease as correlated with relapse. Multiple regression analysis, however, identified only extragastric disease as predictive of relapse (p=0.001). CONCLUSION: Our data demonstrate that both IPI and FLIPI are able to discriminate prognostic subgroups in patients with MALT-lymphoma. However, the low and intermediate group of the FLIPI did not appear to prognostically differ.

[Analysis of the clinical benefits and cost-effectiveness of performing a systematic second-look gastroscopy in benign gastric ulcer]. / Estudio del beneficio clínico y de coste-efectividad tras efectuar sistemáticamente una segunda gastroscopia en la úlcera gástrica benigna.

INTRODUCTION: We analyzed the need to routinely perform a second gastroscopy after an initial diagnosis of benign gastric ulcer. METHOD: A total of 226 consecutive cases of gastric ulcer were reviewed. Sensitivity (S), specificity (Sp), positive and negative predictive value (PPV and NPV) and the accuracy of the initial gastroscopy plus biopsy were analyzed, both overall and according to the initial endoscopist's experience (attending or resident physician). The diagnostic accuracy of the initial and second-look gastroscopies was compared. The number of second endoscopies required to diagnose a new case of malignant gastric ulcer and their cost was calculated, both overall and according to the endoscopist's experience. RESULTS: There were 178 benign ulcers (79%) and 48 malignant ulcers (21%). The initial gastroscopy (S: 87.2%; Sp: 100%; PPV: 100%; PNV: 96.7%; accuracy: 96.7%) was performed by an attending physician in 74% of the patients and by a resident physician in the remaining 26%. Diagnostic accuracy was higher for attending physicians than for residents (98.2% vs. 94.8%; p=0.18). The accuracy of second-look endoscopy was 100%, with a significant improvement when compared with the initial procedure (p=0.035). Three new cases of MALT lymphoma and three new cases of gastric adenocarcinoma were diagnosed and could be treated with curative intent. The number of second gastroscopies required to diagnose a new case of malignant gastric ulcer and their economic cost was: 37.3 (4,675 Euros) for the whole group, 55.2 (6,845 Euros) for attending physicians and 19.3 (2,393 Euros) for residents. CONCLUSIONS: Initial gastroscopy showed high diagnostic accuracy, which was slightly lower when performed by resident physicians. Second-look gastroscopy significantly improved the results, confirming the clinical benefit of this procedure in diagnosing potentially curable malignant lesions. The mean cost of each new diagnosis of malignancy was 4,675 Euros, which was three times lower if the initial gastroscopy was performed by a less experienced endoscopist.

Histopathological assessment and immunohistochemical study of nasopharyngeal low grade MALT lymphoma.

INTRODUCTION: MALT lymphoma arises in a variety of body tissues, but most often in the stomach. Though relatively rare, these MALT lymphomas may arise within several sites in the head and neck, and often present diagnostic and therapeutic challenges. Immunohistochemical analysis are helpful in confirming the diagnosis between the MALT-lymphoma and the reactive lymphoid hyperplasia. MALT-type lymphoma demonstrated characteristic negative staining for CD3, CD5 and CD43, positive staining for CD20, and monotypic staining for either kappa or lambda light chain immunoglobulin markers, whereas reactive lymphoid hyperplasia all expressed B and T cell markers. MATERIAL AND METHODS: 41 Cases of nasopharyngeal masses were obtained from the files at pathology department, Mansoura Faculty of Medicine through the period from 2002 till 2006. 31 cases were corresponded histomorphologically to low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type and 10 patients with reactive lymphoid hyperplasia of the adenoid. Hematoxylin- eosin-stained slides were reviewed to confirm the diagnosis. Immunohistochemical studies were performed on formalin-fixed, paraffin-embedded sections using the labeled streptavidin-biotin-peroxidase complex method with DAB as chromogen. The following antibodies were evaluated CD20, CD3, Kappa, lambda and cytokeratin antibodies. RESULTS: All cases of low grade MALT lymphoma show lymphoepithelial lesion and proliferation of centrocyte like cells. 14 cases (45.1%) show subepithelial plasma cells. Dutcher bodies were demonstrated in 10 cases (32.2%). Monocytoid B-cells were seen in 12 cases (38.7%). Six (60%) out of the ten cases of adenoids show transmigrating lymphocyte without formation of lymphoepithelial lesion. All cases with MALT-type lymphoma expressed CD20 and not CD3 whereas 10 cases of adenoid, all expressed B and T cell markers. Immunohistochemical staining showed that 31 cases of low grade MALT lymphoma were positive for immunoglobin light chain (kappa or lambda) while 10 cases of adenoid were positive for both kappa and lambda light chain. CONCLUSION: Immunohistochemical analysis are helpful in confirming the diagnosis between the MALT-lymphoma and the reactive lymphoid hyperplasia of the nasopharynx.

Interobserver variation in the histopathological assessment of malt/malt lymphoma: towards a consensus.

BACKGROUND: The classification of mucosa associated lymphoid tissue (MALT) lymphoma is based on characteristic morphologic and immunophenotypic patterns, with distinctive chromosomal aberrations. The critical first step is diagnosis on evaluating H&E-stained sections. We performed an inter-observer study to determine the degree of agreement among pathologists in evaluating gastric lymphocytic infiltrates for MALT lymphoma. METHODS: A set of 41 H&E-stained gastric sections (36 endoscopic biopsies and 5 surgically resected sections) that ranged from simple gastritis to primary gastric lymphoma was reviewed separately and independently by 17 participants including hematopathologists, pathologists with a special interest in gastrointestinal pathology, and general pathologists. The participants were from the United States, Europe, and Japan. Results were entered into a standardized data collection form and the results were analyzed using kappa statistics. Monte Carlo simulation was used to adjust for multiple biases. RESULTS: Overall, interobserver reproducibility in the morphologic evaluation of gastric MALT was suboptimal. The kappa statistic was 0.3 for simple gastritis, low-grade MALT and for high grade MALT lymphoma. Monte Carlo simulation suggested that the degree of disagreement was directly related to the pathologist's experience in evaluating gastric biopsies for MALT lesions. However, after conjointly reviewing all cases, the Houston workshop agreed on findings that would increase the reproducibility of diagnosis, especially for pathologists with limited experience with this disease. These included the availability of macroscopic data, extensive sampling, the presence of lymphoepithelial lesions, immunophenotyping and particularly abnormal mucosa localization of B-cells, in addition to other molecular finding such as monoclonality and translocation t (11;18). The group also agreed on the need for standardizing the terminology currently used to facilitate future comparison between studies. CONCLUSIONS: Though the study shows poor agreement on morphologic MALT lymphoma categorization, the Houston workshop suggested recommendations that should increase the diagnostic accuracy and reproducibility of MALT lymphoma diagnosis. A follow up workshop will be organized to measure the diagnostic reproducibility for MALT lymphoma using the suggested recommendations.