Transformation of marginal zone lymphoma into high-grade B-cell lymphoma expressing terminal deoxynucleotidyl transferase:A case report

BACKGROUND High-grade B-cell lymphoma(HGBL)is an unusual malignancy that includes myelocytomatosis viral oncogene(MYC),B-cell lymphoma-2(BCL-2),and/or BCL-6 rearrangements,termed double-hit or triple-hit lymphomas,and HGBL-not otherwise specific(HGBL-NOS),which are morphologically characteristic of HGBL but lack MYC,BCL-2,or BCL-6 rearrangements.HGBL is partially transformed by follicular lymphoma and other indolent lymphoma,with few cases of marginal zone lymphoma(MZL)transformation.HGBL often has a poor prognosis and intensive therapy is currently mainly advocated,but there is no good treatment for these patients who cannot tolerate chemotherapy.CASE SUMMARY We reported a case of MZL transformed into HGBL-NOS with TP53 mutation and terminal deoxynucleotidyl transferase expression.Gene analysis revealed the gene expression profile was identical in the pre-and post-transformed tissues,suggesting that the two diseases are homologous,not secondary tumors.The chemotherapy was ineffective and the side effect was severe,so we tried combination therapy including venetoclax and obinutuzumab.The patient tolerated treatment well,and reached partial response.The patient had recurrence of hepatocellular carcinoma and died of multifunctional organ failure.He survived for 12 months after diagnosis.CONCLUSION Venetoclax combined with obinutuzumab might improve the survival in some HGBL patients,who are unsuitable for chemotherapy.

Endoscopic features of gastro-intestinal lymphomas: From diagnosis to follow-up

Many progresses have been done in the management of gastrointestinal(GI) lymphomas during last decades, especially after the discovery of Helicobacter pylori-dependent lymphoma development. The stepwise implementation of new endoscopic techniques, by means of echoendoscopy or double-balloon enteroscopy, enabled us to more precisely describe the endoscopic features of GI lymphomas with substantial contribution in patient management and in tailoring the treatment strategy with organ preserving approaches. In this review, we describe the recent progresses in GI lymphoma management from disease diagnosis to follow-up with a specific focus on the endoscopic presentation according to the involved site and the lymphoma subtype. Additionally, new or emerging endoscopic technologies that have an impact on the management of gastrointestinal lymphomas are reported. We here discuss the two most common subtypes of GI lymphomas: the mucosaassociated lymphoid tissue and the diffuse large B cell lymphoma. A general outline on the state-of-the-art of the disease and on the role of endoscopy in both diagnosis and follow-up will be performed.

Effectiveness of Helicobacter pylori eradication in the treatment of early-stage gastric mucosa-associated lymphoid tissue lymphoma:An up-to-date meta-analysis

BACKGROUND Gastric mucosa-associated lymphoid tissue(MALT)lymphoma(GML)is usually a low-grade B-cell neoplasia strongly associated with Helicobacter pylori(H.pylori)-induced chronic gastritis.Clinical practice guidelines currently recommend H.pylori eradication as the preferred initial treatment for early-stage GML.To determine the practical effect of bacterial eradication as the sole initial therapy for early-stage GML,an updated analysis and review of available evidence is imperative.AIM To perform a meta-analysis to assess the rate of complete remission(CR)of H.pylori-positive early-stage GML following bacterial eradication.METHODS We performed independent,computer-assisted literature searches using the PubMed/MEDLINE,Embase,and Cochrane Central databases through September 2022.Prospective and retrospective observational studies evaluating the CR of early-stage GML following bacterial eradication in H.pylori-positive patients.The risk of bias was assessed using Joanna Briggs Institute(JBI)Critical Appraisal Tools.The pooled estimate of the complete histopathological remission rate and respective confidence intervals(95%CI)were calculated following the random-effects model.Heterogeneity and inconsistency were assessed using Cochran’s Q test and I2 statistic,and heterogeneity was defined as P<0.01 and I²>50%,respectively.Subgroup and meta-regression analyses were conducted to explore potential sources of heterogeneity.RESULTS The titles and abstracts of 1576 studies were screened;96 articles were retrieved and selected for full-text reading.Finally,61 studies were included in the proportional meta-analysis(P-MA).Forty-six were prospective and fifteen were retrospective uncontrolled,single-arm,observational studies.The overall risk of bias was low to moderate in all but a single report,with an average critical appraisal score across all studies of 79.02%.A total of 2936 H.pylori-positive early-stage GML patients,in whom H.pylori was successfully eradicated,were included in the analysis.The pooled CR of H.pylori-positive early-stage GML after bacterial eradication was 75.18%(95%CI:70.45%-79.91%).P-MA indicated the substantial heterogeneity in CR reported across studies(I2=92%;P<0.01).Meta-regression analysis identified statistically significant effect modifiers,including the proportion of patients with t(11;18)(q21;q21)-positive GML and the risk of bias in each study.CONCLUSION Comprehensive synthesis of available evidence suggests that H.pylori eradication is effective as the sole initial therapy for early-stage GML.Although the substantial heterogeneity observed across studies limits the interpretation of the pooled overall CR,the present study is a relevant to informing clinical practice.

Relationships between lymphomas linked to hepatitis C virus infection and their microenvironment

The relationships between lymphomas and their microenvironment appear to follow 3 major patterns:(1)an independent pattern;(2)a dependent pattern on deregulated interactions;and(3)a dependent pattern on regulated coexistence.Typical examples of the third pattern are hepatitis C virus(HCV)-associated marginal zone lymphomas(MZLs)and mucosa-associated lymphoid tissue lymphomas.In these lymphomas,a regulated coexistence of the malignant cells and the microenvironmental factors usually occurs.At least initially,however,tumor development and cell growth largely depend on external signals from the microenvironment,such as viral antigens,cytokines,and cell-cell interactions.The association between HCV infection and B-cell lymphomas is not completely defined,although this association has been demonstrated by epidemiological studies.MZL and diffuse large B-cell lymphoma are the histotypes most frequently associated with HCV infection.Many mechanisms have been proposed for explaining HCV-induced lymphomagenesis;antigenic stimulation by HCV seems to be fundamental in establishing B-cell expansion as observed in mixed cryoglobulinemia and in B-cell lymphomas.Recently,antiviral treatment has been proved to be effective in the treatment of HCV-associated indolent lymphomas.Importantly,clinically responses were linked to the eradication of the HCV-RNA,providing a strong argument in favor of a causative link between HCV and lymphoproliferation.

Homeostasis and regulation of autoreactive B cells

In contrast to the previous belief that autoreactive B cells are eliminated from the normal repertoire of B cells,many autoreactive B cells actually escape clonal deletion and develop into mature B cells.These autoreactive B cells in healthy individuals perform some beneficial functions in the host and are homeostatically regulated by regulatory T and B cells or other mechanisms to prevent autoimmune diseases.Autoreactive B-1 cells constitutively produce polyreactive natural antibodies for tissue homeostasis.Recently,autoreactive follicular B cells were reported to participate actively in the germinal center reaction.Furthermore,the selection and usefulness of autoreactive marginal zone(MZ)B cells found in autoimmune diseases are not well understood,although the repertoire of MZ B-cell receptors(BCRs)is presumed to be biased to detect bacterial antigens.In this review,we discuss the autoreactive B-cell populations among all three major B-cell subsets and their regulation in immune responses and diseases.

眼附属器黏膜相关淋巴组织结外边缘区淋巴瘤A20及TNF基因的遗传学改变

目的检测眼附属器黏膜相关淋巴组织结外边缘区（MALT）淋巴瘤中A20基因及TNF基因数目的变化，为眼附属器MALT淋巴瘤发病机制的研究提供线索。方法收集原发性眼附属器MALT淋巴瘤石蜡包埋组织标本41例，利用间期荧光原位杂交（FISH）技术，使用商品化6号染色体着丝粒探针及自制位点特异性探针A20和TNF，检测眼附属器MALT淋巴瘤病例中6号染色体、A20以及TNF基因数目的异常。结果41例样本中，A20杂合性缺失2例（4．88％）；TNF基因多拷贝5例（12．20％），其中3例与6号染色体多体同时存在；无A20缺失与TNF多拷贝同时存在的病例。结论中国少部分眼附属器MALT淋巴瘤中存在A20基因杂合性缺失及TNF位点多拷贝的遗传学改变，A20的缺失与TNF位点多拷贝无明显相关性。