胃肠道淋巴瘤中3号染色体三体的表达及其对治疗方案的选择和预后的意义

目的:检测胃肠道黏膜相关淋巴组织淋巴瘤(mucosa-associatedlymphoidtissuelymphoma,MALToma)中3号染色体(chromosome3,C3)三体的发生率,并探讨此变异与该肿瘤的发生关系及在临床治疗中的应用。方法:根据新WHO分类标准,选择33例诊断为胃肠道MALToma的标本,对实验成功的27例进行分型,16例为经典的MALToma,临床为惰性。11例在MALToma基础上有大细胞转化,为转化的MALToma,临床为侵袭性。选用生物素标记的染色体特异的着丝粒探针,采用染色体原位杂交方法,以16号染色体探针作为技术参照组,以胃肠道慢性炎症作为实验对照组,检测肿瘤细胞中3号染色体的拷贝数。结果:在16例惰性MALToma标本中8例为C3三体,8例为正常的C3二倍体;11例转化的MALToma标本中8例为C3三体,3例为正常的C3三体。C3三体在胃肠道MALToma中的发生率达50%,在转化的MALToma中发生率达72.7%,所有的病例都未进行临床系统的抗HP治疗。结论:C3三体在胃肠道黏膜MALToma中发生率较高;该高发生率与肿瘤的发生或演进可能有一定的相关性;并对协助临床诊断及治疗方案的选择具有价值,对患者的临床预后有一定的提示作用。     

胃肠道间质瘤——附4例报告

目的 探讨胃肠道间质瘤的组织发生，病理诊断与鉴别诊断。方法 对4例胃肠道间质瘤标本，用10％福尔马林固定，常规石蜡切片，经HE、免疫组化染色，光镜观察等方法进行研究。结果 瘤细胞呈鱼骨状、栅栏状，车辐状和编织状排列，肿瘤内以梭形细胞为主，上皮样细胞占少数，核呈胖梭形、椭圆形，核染色质较细，核仁不明显。恶性的瘤细胞丰富（例1、3、4），排列紧密，核分裂象（6-20）／50HFP，有粘液和坏死。良性的细胞较少，排列疏松，核分裂象少或无。免疫组化（ABC法）染色：CD1174例均为弥漫强阳性，S-100蛋白（侈14）、α-SMA（例2）为局灶性阳性，CD34均为阴性。例1、3、4诊为恶性胃肠道间质瘤。例2诊为良性间质瘤。结论 胃肠道间质瘤形态结构与平滑肌、神经鞘肿瘤不易鉴别，免疫组化有助于诊断。恶性胃肠道间质瘤，切除后复发率高而且预后差。     

胃肠道淋巴瘤中3号染色体三体的表达及其对治疗方案的选择和预后的意义

目的：检测胃肠道黏膜相关淋巴组织淋巴瘤(mucosa-associated lymphoid tissue lymphoma，MALToma)中3号染色体(chromosome3，C3)三体的发生率，并探讨此变异与该肿瘤的发生关系及在临床治疗中的应用。方法：根据新WHO分类标准，选择33例诊断为胃肠道MALToma的标本，对实验成功的27例进行分型，16例为经典的MALToma，临床为惰性。11例在MALToma基础上有大细胞转化，为转化的MALToma，临床为侵袭性。选用生物素标记的染色体特异的着丝粒探针，采用染色体原位杂交方法，以16号染色体探针作为技术参照组，以胃肠道慢性炎症作为实验对照组，检测肿瘤细胞中3号染色体的拷贝数。结果：在16例惰性MALToma标本中8例为C3三体，8例为正常的C3二倍体；11例转化的MALToma标本中8例为C3三体，3例为正常的C3三体。C3三体在胃肠道MALToma中的发生率达50％，在转化的MAUToma中发生率达72．7％，所有的病例都未进行临床系统的抗HP治疗。结论：C3三体在胃肠道黏膜MALToma中发生率较高；该高发生率与肿瘤的发生或演进可能有一定的相关性；并对协助临床诊断及治疗方案的选择具有价值，对患者的临床预后有一定的提示作用。     

食管胃肠道间质瘤临床病理及免疫组织化学研究

目的　研究食管胃肠道间质瘤的临床、病理及免疫组织化学特征 ,重新认识食管间叶源性肿瘤的组成。方法　用CD117、CD34、vimentin、SMA、S 10 0蛋白 5种抗体对 4 4例食管间叶源性肿瘤进行免疫组织化学SP法染色。结果确诊食管胃肠道间质瘤 9例 ,平滑肌瘤 34例 ,神经纤维瘤 1例。结果　食管内胃肠道间质瘤少见 ,仅占同期间叶源性肿瘤的 2 0 .5 % (9 4 4 ) ,其中良性 6例 ,恶性 3例。结论　胃肠道间质瘤与其他肿瘤的鉴别诊断需要依靠免疫组织化学检测 ,CD117、CD34是诊断间质瘤的特异性抗体。     

CD117与胃肠道间质瘤的诊断及预后关系的研究

目的探讨CD117与胃肠道间质瘤（GIST）的诊断及预后的关系。方法采用EnVision法回顾性分析57例GIST患者CD117、CD34、平滑肌肌动蛋白（SMA）、波形蛋白、S-100的表达情况。结果GIST发生于食管3例（5．3％），胃31例（54．4％），小肠19例（33．3％），结、直肠4例（7．0％）；良性29例（50．9％），交界性20例（35．1％），恶性8例（14．0％）。CD117阳性54例（94．7％），CD34阳性43例（77．2％），14例CD34阴性者CD117均为阳性，波形蛋白阳性56例（98．2％），S-100、SMA阳性分别为6例（10．5％）和3例（5．3％），多为不表达或局灶阳性。肿瘤大小1，5—10．0cm，核分裂像大于5／50HPF的8例中肿瘤直径均大于5．0cm。21例随访病例中良性10例无复发；潜在恶性7例中3例复发，1例死亡，3例无瘤生存：恶性4例中2例死亡，2例复发。无瘤生存者13例，复发带瘤生存5例，死亡3例。良性、潜在恶性和恶性的3年生存率分别为100％（10／10）、71．4％（5／7）和50．0％（2／4）。结论GIST中CD117常弥漫强阳性，CD117是诊断GIST的敏感指标。肿瘤大于或等于5cm，核分裂像大于5／50HPF，有出血或肿瘤坏死可作为恶性参考指标，而且复发率高，3年生存率低，预后较差。     

胃肠道间叶源性肿瘤临床病理及免疫组化分析

目的　研究胃肠道间叶源性肿瘤 (GIMT)的临床病理特征及免疫组化表型 ,从而对该类肿瘤进行更准确的病理诊断。方法　对我院原病理诊断为胃肠道、肠系膜、腹膜后的平滑肌肉瘤、平滑肌瘤、神经鞘瘤、胃肠道间质瘤 (GIST)的病例作回顾性分析 ,应用免疫组织化学方法观察 5种抗体 (CD117、CD34、S 10 0、desmin、Ki- 6 7)的表达 ,分析其临床病理特点。结果　 4 5例GIMT中GIST 33例占 73. 3%、平滑肌肿瘤 7例占15 . 6 %、神经鞘瘤 1例占 2 . 2 %、4例各种免疫表型均阴性 ,为不能分类者。在GIST中CD117阳性率为6 0 . 6 %、CD34阳性率 90. 9%、CD117和CD34共同阳性 17例 ,占 5 1 .5 3%。结论　消化道间叶源性肿瘤以GIST最多见 ,平滑肌肿瘤和神经鞘瘤非常少见 ,光镜下鉴别十分困难。CD117、CD34、S 10 0、desmin联合检测 ,能对其进行更准确的病理诊断和鉴别诊断 ,Ki- 6 7可作为判断其良恶性的辅助指标。     

18例胃间质瘤临床病理分析

目的 探讨胃间质瘤的病理组织学特点、免疫表型特征、诊断标准、治疗原则及决定预后的因素.方法 对18例胃间质瘤患者的手术切除标本用10%甲醛固定,常规HE染色、光镜观察,SP染色后检测CD117、CD34、平滑肌肌动蛋白(SMA)、S100蛋白的表达.结果 18例胃间质瘤的病理形态呈梭形细胞样12例,上皮细胞样6例,CD117阳性+ 6例、++ 8例、+++ 4例,CD34 + 8例、++ 2例,+++ 6例、阴性2例,S100蛋白仅有1例散在阳性,SMA仅有2例散在阳性,其余均为阴性.结论 CD117、CD34是胃间质瘤的诊断标记物,病理检查及免疫组织化学是诊断胃间质瘤的可靠方法,肿瘤大小及核分裂是判断危险度的标准,手术切除是首选的治疗方法.术后密切随访、定期复查,必要时配合甲磺酸伊马替尼治疗对控制复发、转移,延长患者生命有重要意义.     

胃肠道间质瘤的免疫表型及其起源分类探讨

目的：从胃肠道间质瘤的免疫表型探讨其起源及分类。方法：采用微波修复抗原及免疫组织化学S－P法检测34例胃肠道间质瘤患CD117、CD34、Vimentin、Desmin、SMA、MSA、S－100、NSE和NF的表达。结果：病理学诊断良性11例、恶性11例、交界瘤12例，平均直径7．9cm，平均核分裂数6个／10HPF，并随I、Ⅱ、Ⅲ分级增高而增多。免疫组化染色证实：CD117阳性34例（100％）、CD34阳性28例（82．4％），Vimentin阳性18例（52．9％），Desmin阳性9例（26．5％），SMA阳性10例（29．4％），MSA阳性7例（20．6％），S100阳性11例（32．4％），NSE阳性7例（20．6％）及NF阳性13例（38．2％）。根据其免疫表型，34例GIST存在4种类型：狭义GIST3例（1例恶性、2例良性）、biphasic type6例、neurogenic type13例及myogenic type12例，随访11例恶性肿瘤中有3例复发，5例死亡，均为Ⅱ、Ⅲ级，其平均核分裂数13个／10HPF。结论：肿瘤大小、核分裂数为GIST良恶性诊断的重要指标，免疫组化染色有助于探寻肿瘤细胞起源及分类。     

胃肠道间质瘤22例临床诊治

目的 探讨胃肠道间质瘤的诊治、临床病理学及免疫组织化学特征。方法 回顾分析1998—2005年外科收治并经病理证实的22例胃肠道间质瘤（GIST）的临床资料。结果 22例均行手术治疗。病理诊断GIST良性6例,交界性3例,恶性13例。免疫组织化学表型CD117阳性19例,CD34阳性18例,Vimentin阳性19例,SMA阳性3例,S-100蛋白阳性5例,Desmin阳性3例。随访6～84个月,3例出现远处转移或局部复发,5例死亡。结论 GIST缺乏特征性临床表现,术前确诊率较低,其确诊依赖于病理结果与免疫组织化学的结合,手术切除是最有效的治疗手段。     

297例自身免疫性疾病ANA和抗ENA抗体联合检测分析

目的分析其中ANA表达阳性而抗ENA抗体表达阴性的样本的检验学特征及意义。方法对297例样本运用间接免疫荧光法检测ANA,生物芯片技术检测抗ENA抗体,并采用双盲法分析ANA阳性标本的荧光核型。从已知的ANA阳性患者血清中筛选其ENA表达均为阴性的患者血清,比对其荧光核型并进行分析。结果 297例临床标本中,ANA阳性标本数为74例,阳性率为24.9%(74/297)。其主要核型为核浆颗粒型(43例,58.1%)、胞浆颗粒型(9例,12.2%)、核浆点型(9例,12.2%)。在74例ANA阳性标本中,抗ENA抗体为阴性的标本数为13例,占阳性标本的17.6%。13例标本中有11例表现为核浆颗粒型,占84.6%;1例表现为胞浆颗粒型,占7.7%;1例表现为核浆点型,占7.7%。结论在ANA阳性同时抗ENA抗体表达为阴性的患者血清中,核浆颗粒型明显高于胞浆颗粒型与核浆点型在ANA标本中的阳性率,并且远大于核浆颗粒型在抗ENA抗体表现为阳性的ANA阳性标本中的比例(52.5%),差异有统计学意义(χ2=5.018,P0.05)。在抗ENA抗体表现为阴性的ANA阳性标本中,荧光核型表现为核浆颗粒型有其自身特有的临床意义有助于筛选发现抗ENA抗体以外的新自身抗体。     

T(11;18)及核bcl-10蛋白在胃肠MALT淋巴瘤中的表达

为了探讨t(11；18)(q21；q21)染色体易位及核bcl-10蛋白在胃肠粘膜相关淋巴组织淋巴瘤(MALT lymphoma)中的表达，用酸性酚氯仿法从石蜡组织中提取RNA；逆转录合成cDNA后用聚合酶链反应(PCR)扩增API2-MALT1融合基因；用免疫组织化学法检测石蜡切片中bcl—10蛋白的表达。结果表明：42例MALT淋巴瘤中，t(11；18)(q21；q21)染色体易位在低度恶性MALT淋巴瘤中的表达为14％，在伴高恶转化型MALT淋巴瘤中的表达为46％，在40例弥漫大B细胞淋巴瘤(diffuse 1arge B cell lymphoma，DLBCL)对照组中没有表达；43例MALT淋巴瘤中bcl-10蛋白在低度恶性MALT淋巴瘤的核表达为61％，在伴高恶转化型MALT淋巴瘤中的核表达为69％。结论：t(11；18)易位可能与高度进展MALT淋巴瘤有一定相关性，但与DLBCL无关;bcl-10蛋白的核表达在恶性程度不同的两组MALT淋巴瘤中无显著性差异，其原因有待进一步研究。     

肠道黏膜相关淋巴组织淋巴瘤3号染色体三体的研究

目的　检测肠道黏膜相关淋巴组织 (MALT)淋巴瘤中 3号染色体三体 (C3三体 )的发生率 ,并探讨此变异与该肿瘤发生的关系。方法　 11例诊断为肠道MALT淋巴瘤的标本 ,根据新的WHO分类标准 ,对实验成功的 8例进行分型 ,7例为经典MALT型淋巴瘤 ,临床为惰性 ;1例在MALT型淋巴瘤基础上有大细胞转化 ,临床为侵袭性。实验中选用生物素标记的染色体特异的着丝粒探针 ,采用染色体原位杂交方法 ,以 16号染色体探针作为技术参照组 ,以肠道慢性炎症作为实验对照组 ,检测肿瘤细胞中 3号染色体的拷贝数。结果　在 7例惰性淋巴瘤患者中 5例为C3三体 ,发生率为 71.4 % ,2例为C3正常 ;1例侵袭性病例为C3三体。结论　C3三体在肠道MALT淋巴瘤中发生率较高 ,该高发生率与肿瘤的发生或演进可能有一定的相关性 ,并对协助临床诊断可能具有价值。     

口咽部B细胞来源非霍奇金淋巴瘤的CT诊断

目的：分析口咽部B细胞来源非霍奇金淋巴瘤（NHL）的CT表现、特征,初步探讨不同病理类型B细胞来源NHL的CT表现特点,为临床诊断和治疗提供更为准确的信息。方法：对18例经病理证实的口咽部B细胞来源非霍奇金淋巴瘤的CT表现进行回顾性分析。结果：18例中,弥漫大B细胞淋巴瘤13例,占72．2％（13／18）,滤泡性淋巴瘤3例,占16．7％（3／18）,套细胞淋巴瘤1例,占5．6％（1／18）,结外边缘区淋巴瘤（MALT淋巴瘤）1例,占5．6％（1／18）。病变分布为：扁桃体NHL9例（弥漫大B细胞淋巴瘤8例、套细胞淋巴瘤1例）;舌根8例（弥漫大B细胞淋巴瘤5例、滤泡性淋巴瘤3例）;软腭1例,为结外边缘区淋巴瘤（MALT淋巴瘤）。18例病变均表现为肿块型。同时有淋巴结受累者12例（66．7％）,其中双侧受累者3例。结论：口咽B细胞来源NHL多发生于扁桃体及舌根。病理类型以弥漫大B细胞淋巴瘤为主,主要表现为肿块。CT对于B细胞来源NHL的鉴别诊断和病变范围的判断具有重要作用。     

Diminished expression of CD19 in B-cell lymphomas

BACKGROUND: CD19 is expressed on most B-cell lymphomas; however, the frequency and types of B-cell lymphomas with low-level expression of CD19 are not well characterized. METHODS: We reviewed flow cytometric histograms specifically for decreased CD19 expression on 349 cases analyzed by the Flow Cytometry Laboratory at University Hospitals of Cleveland (Cleveland, Ohio). Results of flow cytometry were correlated with the morphologic diagnosis. RESULTS: Of the cases reviewed, 125 (36%) showed a visible decrease in CD19 expression compared with normal B lymphocytes. Decreased CD19 expression was noted in 79% of follicular lymphomas (27 of 34), 36% of small lymphocytic lymphomas/chronic lymphocytic leukemias (82 of 228), 31% of mantle cell lymphomas (4 of 13), 24% of diffuse large B-cell lymphomas (8 of 33), and 13% of marginal zone B-cell lymphomas/lymphoplasmacytoid lymphomas (4 of 30) and was not observed in any Burkitt lymphoma (0 of 5) or hairy cell leukemia (0 of 6). Decreased CD19 expression was significantly more frequent in follicular lymphomas than in other lymphoma subtypes (P < 0.001). No significant difference was observed in the frequency of decreased CD19 expression based on histologic grade of follicular lymphoma. CONCLUSIONS: Diminished expression of CD19 expression occurs frequently in B-cell lymphomas, in particular follicular lymphoma, and may be helpful in identifying B-cell lymphoma cells in complex cell mixtures such as bone marrow specimens.     

Clinicopathological features of malignant lymphoma in Japan: the Miyagi Study

The Miyagi Study is an epidemiological study of malignant lymphoma, including immunological and genetic analyses, constructed by a population-based registration system covering Miyagi prefecture, Japan. A total of 1,552 newly diagnosed cases in Miyagi between 2002 and 2008 were enrolled in this study; 75% were B-cell lymphomas, 19% were T-cell and natural killer-cell (T/NK-cell) lymphomas, and 5% were Hodgkin's lymphomas. The most frequent subtype of B-cell lymphoma is diffuse large B-cell lymphoma, followed by follicular lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (51%, 24% and 8%, respectively). Thus, follicular lymphoma accounts for 18.2% of newly diagnosed cases in Miyagi; unexpectedly, its frequency is similar to that reported in Western countries. The common subtypes of T/NK-cell lymphoma are peripheral T-cell lymphoma, angioimmunoblastic T-cell lymphoma, and adult T-cell leukemia/lymphoma (30%, 15% and 14%, respectively). Most of the data are similar to those reported in Asian countries, except for follicular lymphoma. We also analyzed the CD20 expression in B-cell lymphomas by flow cytometry for the cell membrane expression and by immunohistochemistry for the cytoplasmic expression. The cell membrane expression of CD20 protein may determine the susceptibility of B-cell lymphomas to anti-CD20 antibody therapy. The lack of CD20 expression was confirmed by both methods in 4 cases of 585 newly diagnosed cases (0.7%) and in 5 of 67 recurrent cases (7.5%). Furthermore, 23 cases (6.5%) showed the discrepancy of CD20 expression between both methods. The Miyagi Study has revealed the latest epidemiological features of malignant lymphoma in Japan.     

Analytical detection of immunoglobulin heavy chain gene rearrangements in gastric lymphoid infiltrates by peak area analysis of the melting curve in the LightCycler System

Because it is difficult to differentiate gastric mucosa-associated lymphoid tissue (MALT) lymphoma from chronic gastritis in gastric lymphoid infiltrates, molecular detection of monoclonality through immunoglobulin heavy chain (IgH) gene rearrangements is commonly performed. However, heterogeneity in the performance and results obtained from IgH gene rearrangements has been reported. To improve the accuracy in the diagnosis of gastric lymphoid infiltrates, we developed an analytical approach based on one-peak area analysis of the melting curve in the LightCycler System. Using a training-testing approach, the likelihood ratio method was selected to find a discriminative function of 4.64 in the training set (10 gastric MALT lymphomas and 10 chronic gastritis cases). This discriminative function was validated in the testing set (five gastric MALT lymphomas, six abnormal lymphocytic infiltrates with subsequently demonstrated gastric MALT lymphomas, and six cases of chronic gastritis). All but one case of gastric MALT lymphoma, as well as abnormal lymphocytic infiltrates, clustered under 4.64, and all chronic gastritis cases clustered above 4.64. These results were validated by conventional electrophoreses confirming one or two sharp bands in cases of gastric MALT lymphomas and a smear of multiple bands in cases of chronic gastritis. Analytical detection of IgH gene rearrangement in gastric lymphoid infiltrates by one-peak area analysis correctly distinguishes gastric MALT lymphomas from chronic gastritis, even in cases with diagnosis of abnormal lymphocytic infiltrates.     

眼附属器及胃肠MALT型淋巴瘤Ki-67和p53表达对患者生存期及预后评估的意义

目的研究眼附属器MALT型淋巴瘤Ki-67和p53表达对临床治疗的选择和预后评估的意义.方法采用免疫组化的方法,检测29例眼附属器MALT型淋巴瘤Ki-67和p53表达,分析其在不同临床特征间的差异;并与15例胃肠MALT型淋巴瘤的Ki-67和p53表达进行对比.结果29例眼附属器MALT型淋巴瘤在不同的年龄、性别、发病部位Ki-67和p53表达差异无显著性.在分期上,2例非Ⅰ期病例出现了Ki-67的高表达.与胃肠MALT淋巴瘤对比,29例眼附属器MALT型淋巴瘤未见有高恶转化,p53表达程度低;15例胃肠MALT淋巴瘤有5例出现高恶转化,3例p53高表达.结论Ki-67和p53的高表达对眼附属器MALT型淋巴瘤的临床分期和高恶转化有一定的提示作用,与胃肠MALT型淋巴瘤相比,Ki-67和p53表达率、表达程度低,提示预后较好.     

肠MALT淋巴瘤细胞凋亡与p53和bcl—2的表达

目的：探讨肠黏膜相关淋巴组织（MALT）淋巴瘤细胞增殖和凋亡的特征以及调亡相关调控基因的表达。方法：应用TUNEL技术检测21例肠淋巴瘤的凋亡指数（apoptosis index,AI),免疫组化S－P法检测PCNA增殖指数（proliferative index,PI）及bcl-2和p5e蛋白的表达。结果：随着肠MALT淋巴瘤恶性度的增高,AI和PI显著增加,并且二者呈显著正相关。低度恶性、高度恶性伴低度恶性以及高度恶性肿瘤组中,bcl-2阳性率分别为79．4％、57．1％、40．9％。三组bcl-2呈阳性率为AI均差异显著（P＜0．05）。bcl-2与AI呈显著负相关（P＜0．05）。p53阳性率为31．4％。高度恶性组p53阳性率显著高于其余两组。p53与bcl-2表达呈负相关（P＜0．05）。结论：凋亡和增殖在肿瘤的发生、发展、转化中起着重要作用,检测AI、PI可能是诊断恶性淋巴瘤、评价其生物学行为的可靠指标。在MALT的恶性度从低到高的转化中,p53和bcl-2基因可能起着重要作用。     

Delving deeper into MALT lymphoma biology

Mucosa-associated lymphoid tissue (MALT) lymphomas can arise in a variety of extranodal sites. Interestingly, at least 3 different, apparently site-specific, chromosomal translocations, all affecting the NF-kappaB pathway, have been implicated in the development and progression of MALT lymphoma. The most common is the translocation t(11;18)(q21;q21), which results in a fusion of the cIAP2 region on chromosome 11q21 with the MALT1 gene on chromosome 18q21 and is present in more than one-third of cases. The frequency of this translocation is site-related: common in the gastrointestinal tract and lung, rare in conjunctiva and orbit, and almost absent in salivary glands, thyroid, liver, and skin. In this issue of the JCI, Hu et al. add to our understanding of the molecular consequences of this translocation, showing that its fusion product, cIAP2-MALT1, may concomitantly contribute to lymphomagenesis both as a tumor suppressor gene and as an oncogene.     

Laterally spreading tumor-like primary rectal mucosa-associated lymphoid tissue lymphoma: A case report

BACKGROUNDColorectal mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease, and only a few cases have been reported to date. It has no specific clinical presentations and shows various endoscopic appearances. There is no uniform consensus on its treatment. With the advancement of endoscopic technology, endoscopic treatment has achieved better results in individual case reports of early-stage patients.CASE SUMMARYWe report a case of rectal MALT in a 57-year-old Chinese man with no symptoms who received endoscopy as part of a routine physical examination, which incidentally found a 25 mm × 20 mm, laterally spreading tumor (LST)-like elevated lesion in the rectum. Therefore, he was referred to our hospital for further endoscopic treatment. Complete and curable removal of the tumor was performed by endoscopic submucosal dissection. We observed enlarged and dilated branch-like vessels similar to those of gastric MALT lymphoma on magnifying endoscopy with narrow-band imaging. And immunopathological staining showed hyperplastic capillaries in the mucosa. Histopathological findings revealed diffusely hyperplastic lymphoid tissue in the lamina propria, with a visible lymphoid follicle structure surrounded by a large number of diffusely infiltrated lymphoid cells that had a relatively simple morphology and clear cytoplasm. In addition, immunohistochemical analysis suggested strongly positive expression for CD20 and Bcl-2. Gene rearrangement results showed positivity for IGH-A, IGH-C, IGK-B, and IGL. Taking all the above findings together, we arrived at a diagnosis of extranodal marginal zone B-cell lymphoma of MALT lymphoma. Positron emission tomography-computed tomography examination showed no other lesions involved. The patient will be followed by periodic endoscopic observation.CONCLUSIONIn conclusion, we report a case of rectal MALT with an LST-like appearance treated by endoscopic submucosal dissection. Further studies will be needed to explore the clinical behavior, endoscopic appearance, and treatment of rectal MALT.