Rare incidence of mucosa-associated lymphoid tissue lymphoma presenting as buccal fat pad tumor:A case report

BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma,a type of non-Hodgkin lymphoma,originates in the mucosal lining of body organs and internal cavities,including the nose,mouth,lungs,and digestive tract.The lymphoma develops when the body produces abnormal B lymphocytes.These lymphomas develop at the edge of the lymphoid tissue,called the marginal zone,and,hence,are classified as a type of marginal zone lymphomas.They are the most common type of marginal zone lymphomas although their occurrence is rare.To date,no previous cases of MALT lymphoma in the buccal fat pad have been reported.CASE SUMMARY We report the case of a patient who presented with a mass on the frontal cheek.Magnetic resonance imaging revealed a tumor in the buccal fat pad,and histopathological and immunohistochemical findings confirmed the diagnosis of MALT lymphoma.The patient had a history of Helicobacter pylori and hepatitis C virus infection,suggesting an association between these infective agents and MALT lymphoma.CONCLUSION Consideration of MALT lymphoma is essential in the differential diagnosis of frontal cheek masses.

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.

Role of non-Helicobacter pylori gastric Helicobacters in helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma

Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma,trailing behind diffuse large B-cell lymphoma and follicular lymphoma.Gastric mucosa-associated lymphoid tissue lymphoma(GML)is a low-grade B-cell neoplasia frequently correlated with Helicobacter pylori(H.pylori)-induced chronic gastritis.On the other hand,a specific subset of individuals diagnosed with GML does not exhibit H.pylori infection.In contrast to its H.pylori-positive counterpart,it was previously believed that H.pylori-negative GML was less likely to respond to antimicrobial therapy.Despite this,surprisingly,increasing evidence supports that a considerable proportion of patients with H.pylori-negative GML show complete histopathological remission after bacterial eradication therapy.Nonetheless,the precise mechanisms underlying this treatment responsiveness are not yet fully comprehended.In recent years,there has been growing interest in investigating the role of non-H.pylori gastric helicobacters(NHPHs)in the pathogenesis of H.pylori-negative GML.However,additional research is required to establish the causal relationship between NHPHs and GML.In this minireview,we examined the current understanding and proposed prospects on the involvement of NHPHs in H.pylori-negative GML,as well as their potential response to bacterial eradication therapy.

Mucosa-associated lymphoid tissue lymphoma of the trachea treated with radiotherapy:A case report

BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma originates in the marginal zone of lymphoid tissue.lung is one of the most frequent non-gastrointestinal organs involved,here known as bronchus-associated lymphoid tissue(BALT)lymphoma.BALT lymphoma of unknown etiology,and most patients are asymptomatic.The treatment of BALT lymphoma is controversial.CASE SUMMARY A 55-year-old man admitted to hospital had a three-month history of progressively coughing up yellow sputum,chest stuffiness,and shortness of breath.Fiberoptic bronchoscopy revealed mucosal visible beaded bumps 4 cm from the tracheal carina at 9 o'clock and 3 o'clock,the right main bronchus,and the right upper lobe bronchus.Biopsy specimens showed MALT lymphoma.Computed tomography virtual bronchoscopy(CTVB)showed uneven main bronchial wall thickening and multiple nodular protrusion.BALT lymphoma stage IE was diagnosed after a staging examination.We treated the patient with radiotherapy(RT)alone.A total dose of 30.6 Gy/17 f/25 d was given.The patient had no obvious adverse reactions during RT.The CTVB was repeated after RT and showed that the right side of the trachea was slightly thickened.CTVB was repeated 1.5 mo after RT and again showed that the right side of the trachea was slightly thickened.Annual CTVB showed no signs of recurrence.The patient now has no symptoms.CONCLUSION BALT lymphoma is an uncommon disease and shows good prognosis.The treatment of BALT lymphoma is controversial.In recent years,less invasive diagnostic and therapeutic approaches have been emerging.RT was effective and safe in our case.The use of CTVB could provide a noninvasive,repeatable,and accurate method in diagnosis and follow-up.

Nomogram model predicting the overall survival for patients with primary gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND Increasingly extranodal marginal B-cell lymphoma of mucosa-associated lymphoid tissue,known as mucosa-associated lymphoid tissue(MALT)lymphoma,is a type of non-Hodgkin’s lymphoma.The prognosis of primary gastric MALT(GML)patients can be affected by many factors.Clinical risk factors,including age,type of therapy,sex,stage and family hematologic malignancy history,also have significant effects on the development of the disease.The available data are mainly focused on epidemiology;in contrast,few studies have investigated the prognostic variables for overall survival(OS)in patients with primary GML.Based on the realities above,we searched a large amount of data on patients diagnosed with primary GML in the Surveillance,Epidemiology and End Results(SEER)database.The aim was to develop and verify a survival nomogram model that can predict the overall survival prognosis of primary GML by com-bining prognostic and determinant variables.AIM To create an effective survival nomogram for patients with primary gastric GML.METHODS All data of patients with primary GML from 2004 to 2015 were collected from the SEER database.The primary endpoint was OS.Based on the LASSO and COX regression,we created and further verified the accuracy and effectiveness of the survival nomogram model by the concordance index(C-index),calibration curve and timedependent receiver operating characteristic(td-ROC)curves.RESULTS A total of 2604 patients diagnosed with primary GML were selected for this study.A total of 1823 and 781 people were randomly distributed into the training and testing sets at a ratio of 7:3.The median follow-up of all patients was 71 mo,and the 3-and 5-year OS rates were 87.2%and 79.8%,respectively.Age,sex,race,Ann Arbor stage and radiation were independent risk factors for OS of primary GML(all P<0.05).The C-index values of the nomogram were 0.751(95%CI:0.729-0.773)and 0.718(95%CI:0.680-0.757)in the training and testing cohorts,respectively,showing the good discrimination ability of the nomogram model.Td-ROC curves and calibration plots also indicated satisfactory predictive power and good agreement of the model.Overall,the nomogram shows favorable performance in discriminating and predicting the OS of patients with primary GML.CONCLUSION A nomogram was developed and validated to have good survival predictive performance based on five clinical independent risk factors for OS for patients with primary GML.Nomograms are a low-cost and convenient clinical tool in assessing individualized prognosis and treatment for patients with primary GML.

Primary rectal mucosa-associated lymphoid tissue lymphoma treated with only endoscopic submucosal dissection:A case report

BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma is a distinct subtype of non-Hodgkin B cell lymphoma that mostly involves the gastrointestinal tract.The stomach is the most commonly affected site whereas colorectal involvement occurs very rarely.Given its rarity,the management and clinical outcome of colorectal MALT lymphoma are not well established yet.CASE SUMMARY From the superficial capillary bed in the lower rectum.Endoscopic ultrasonography showed homogenous hypoechoic lesions in the deep mucosal layer.Endoscopic submucosal dissection(ESD)was done for accurate histologic diagnosis and treatment and both the rectal lesions were completely removed en bloc and subsequently diagnosed as primary rectal MALT lymphoma.Herein,we report a case of primary rectal MALT lymphoma in a 68-year-old woman that was treated by only ESD,and the 12-month follow-up revealed no tumour recurrence.CONCLUSION These results of our case and previous reports suggest that endoscopic resection alone may be a feasible and safe treatment for primary colorectal MALT lymphoma and allows organ preservation.

Role of Helicobacter pylori in gastric mucosa-associated lymphoid tissue lymphomas

Mucosa-associated lymphoid tissue (MALT) lymphoma is an indolent extranodal marginal zone B-cell lymphoma, originating in acquired MALT that is induced in mucosal barriers as part of a normal adaptive immune response to a chronic immunoinflammatory stimulus, most notably chronic infection by Helicobacter pylori (H. pylori). This antigenic stimulation initially leads to lymphoid hyperplasia; the acquisition of additional genetic aberrations culminates in the activation of intracellular survival pathways, with disease progression due to proliferation and resistance to apoptosis, and the emergence of a malignant clone. There are descriptions of MALT lymphomas affecting practically every organ and system, with a marked geographic variability partially attributable to the epidemiology of the underlying risk factors; nevertheless, the digestive system (and predominantly the stomach) is the most frequently involved location, reflecting the gastrointestinal tract’s unique characteristics of contact with foreign antigens, high mucosal permeability, large extension and intrinsic lymphoid system. While early-stage gastric MALT lymphoma can frequently regress after the therapeutic reversal of the chronic immune stimulus through antibiotic eradication of H. pylori infection, the presence of immortalizing genetic abnormalities, of advanced disease or of eradication-refractoriness requires a more aggressive approach which is, presently, not consensual. The fact that MALT lymphomas are rare neoplasms, with a worldwide incidence of 1-1.5 cases per 105 population, per year, limits the ease of accrual of representative series of patients for robust clinical trials that could sustain informed evidence-based therapeutic decisions to optimize the quality of patient care.

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

BACKGROUND Colorectal 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 SUMMARY We 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 tomographyexamination showed no other lesions involved. The patient will be followed byperiodic endoscopic observation.CONCLUSIONIn conclusion, we report a case of rectal MALT with an LST-like appearancetreated by endoscopic submucosal dissection. Further studies will be needed toexplore the clinical behavior, endoscopic appearance, and treatment of rectalMALT.

A case of mucosa-associated lymphoid tissue lymphoma forming multiple lymphomatous polyposis in the small intestine

A 50-year old woman suffering from diabetes had a CT scan that revealed a diffuse thickening of small intestinal wall and swollen paraaortic lymph nodes. An esophago gastroduodenoscopy (EGD) confirmed multiple polypoid lesions in the duodenum and small intestine, and conventional histological testing revealed non-specific inflammatory changes. Further examinations including the immunohistochemical profiles of the biopsied specimens led us to diagnose the lesion as a marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type, forming multiple lymphomatous polyposis sequentially spreading from duodenal bulb to terminal ileum. According to Lugano’s classification, its staging was clinically diagnosed as stage Ⅱ. Two courses of a standard CHOP (cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, and predonisolone) regimen with rituximab reduced the lesion and the patient had a almost complete response. A 5-year follow- up EGD and histological examinations detected no recurrence of the disease.

Primary mucosa-associated lymphoid tissue lymphoma in the midbrain:A case report

BACKGROUND Primary non-dural central nervous system mucosa-associated lymphoid tissue(MALT)lymphoma is a rare indolent B-cell lymphoma,with only a few reported cases worldwide.CASE SUMMARY A 33-year-old man presented with a 5-mo history of left blepharoptosis and a 4-mo history of right limb numbness and weakness.Magnetic resonance imaging showed a significantly enhanced mass in the left midbrain.Subsequent positron emission tomography revealed that the lesion had increased glucose uptake.A stereotactic robotic biopsy supported a diagnosis of MALT lymphoma.Then he was treated with radiation therapy(30Gy/15F),which resulted in complete remission.We also review the literature on brain parenchymal-based MALT lymphoma,including the clinical presentation,treatment options,and outcomes.CONCLUSION Although there is no consensus on the optimal treatment for this rare disease,patients can respond well when treated with radiotherapy alone.

Role of Helicobacter pylori virulence factor cytotoxin-associated gene A in gastric mucosa-associated lymphoid tissue lymphoma

Helicobacter pylori(H.pylori)infection might initiate and contribute to the progression of lymphoma from gastric mucosa-associated lymphoid tissue(MALT).Increasing evidence shows that eradication of H.pylori with antibiotic therapy can lead to regression of gastric MALT lymphoma and can result in a 10-year sustained remission.The eradication of H.pylori is the standard care for patients with gastric MALT lymphoma.Cytotoxin-associated gene A(CagA)protein,one of the most extensively studied H.pylori virulence factors,is strongly associated with the gastric MALT lymphoma.CagA possesses polymorphisms according to its C-terminal structure and displays different functions among areas and races.After being translocated into B lymphocytes via typeⅣsecretion system,CagA deregulates intracellular signaling pathways in both tyrosine phosphorylation-dependent and-independent manners and/or some other pathways,and thereby promotes lymphomagenesis.A variety of proteins including p53and protein tyrosine phosphatases-2 are involved in the malignant transformation induced by CagA.Mucosal inflammation is the foundational mechanism underlying the occurrence and development of gastric MALT lymphoma.

Helicobacter pylori infection in gastric mucosa-associated lymphoid tissue lymphoma

Gastrointestinal lymphoma is the most common type of extranodal lymphoma,and most commonly affects the stomach.Marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue(MALT)and diffuse large B-cell lymphoma are the most common histologic types of gastric lymphoma.Despite its increasing incidence,diagnosis of gastric lymphoma is difficult at an earlier stage due to its nonspecific symptoms and endoscopic findings,and,thus,a high index of suspicion,and multiple,deep,repeated biopsies at abnormally and normally appearing sites in the stomach are needed.In addition,testing for Helicobacter pylori(H.pylori)infection and endoscopic ultrasonography to determine the depth of tumor invasion and involvement of regional lymph nodes is essential for predicting response to H.pylori eradication and for assessment of disease progression.In addition,H.pylori infection and MALT lymphoma development are associated,and complete regression of low-grade MALT lymphomas after H.pylori eradication has been demonstrated.Radiotherapy and/or chemotherapy can be used in cases that show poor response to H.pylori eradication,negativity for H.pylori infection,or high-grade lymphoma.

Helicobacter pylori and gastric mucosa-associated lymphoid tissue lymphoma:Recent progress in pathogenesis and management

Recent progress in the research regarding the molecular pathogenesis and management of gastric mucosa-associated lymphoid tissue (MALT) lymphoma is reviewed. In approximately 90% of cases, Helicobacter pylori (H. pylori) infection plays the causative role in the pathogenesis, and H. pylori eradication is nowadays the first-line treatment for this disease, which leads to complete disease remission in 50%-90% of cases. In H. pylori-dependent cases, microbe-generated immune responses, including interaction between B and T cells involving CD40 and CD40L co-stimulatory molecules, are considered to induce the development of MALT lymphoma. In H. pylori-independent cases, activation of the nuclear factor-&#x003ba;B pathway by oncogenic products of specific chromosomal translocations such as t(11;18)/API2-MALT1, or inactivation of tumor necrosis factor alpha-induced protein 3 (A20) are considered to contribute to the lymphomagenesis. Recently, a large-scale Japanese multicenter study confirmed that the long-term clinical outcome of gastric MALT lymphoma after H. pylori eradication is excellent. Treatment modalities for patients not responding to H. pylori eradication include a &#x0201c;watch and wait&#x0201d; strategy, radiotherapy, chemotherapy, rituximab immunotherapy, and a combination of these. Because of the indolent behavior of MALT lymphoma, second-line treatment should be tailored in consideration of the clinical stage and extent of the disease in each patient.

Gastric mucosa-associated lymphoid tissue lymphomas and Helicobacter pylori infection:A Colombian perspective

AIM： To assess the significance of chromosome translo- cation t（11;18）（q21;q21）, B-cell lymphoma 10 （BCL-10） protein and He/icobacter py/ori （H. py/on） infection in gastric mucosa-associated lymphoid tissue （MALT） lymphoma in Colombia.

Primary thymic mucosa-associated lymphoid tissue lymphoma with multiple thin walled lung cysts: case report and literature review

Mucosa-associated lymphoid tissue （MALT） lymphoma of the thymus is rare. We reported a case of a 37-year-old Chinese female with Sjtgren＇s syndrome and hyperglobulinemia. She suffered from chronic cough for 3 weeks. Chest computed tomography （CT） demonstrated a multiloculated cystic mass in mediastinum prevascular space and multiple lung cysts. Laboratory exam of autoimmune markers showed positive of antinuclear antibody （ANA）, Sjtgren＇s syndrome A （SSA）, Sjtgren＇s syndrome B （SSB）, and rheumatoid factors （RF）. Thymectomy with lymph node dissection was performed. The pathology report revealed thymic extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue. Under immunohistochemical stains, CD20 and Bcl-2 were positive. No evidence of recurrence of disease was found.

Management of gastric mucosa-associated lymphoid tissue lymphoma in patients with extra copies of the MALT1 gene

AIM To identify the clinical features of gastric mucosaassociated lymphoid tissue(MALT) lymphoma with extra copies of MALT1.METHODS This is a multi-centered,retrospective study. We reviewed 146 patients with MALT lymphoma in the stomach who underwent fluorescence in situ hybridization analysis for t(11;18) translocation. Patients were subdivided into patients without t(11;18) translocation or extra copies of MALT1(Group A,n = 88),patients with t(11;18) translocation(Group B,n = 27),and patients with extra copies of MALT1(Group C,n = 31). The clinical background,treatment,and outcomes of each group were investigated.RESULTS Groups A and C showed slight female predominance,whereas Group B showed slight male predominance. Mean ages and clinical stages at lymphoma diagnosis were not different between groups. Complete response was obtained in 61 patients in Group A(69.3%),22 in Group B(81.5%),and 21 in Group C(67.7%). Helicobacter pylori(H. pylori) eradication alone resulted in complete remission in 44 patients in Group A and 13 in Group C. In Group B,14 patients underwent radiotherapy alone,which resulted in lymphoma disappearance. Although the difference was not statistically significant,event-free survival in Group C tended to be inferior to that in Group A(P = 0.10).CONCLUSION Patients with t(11;18) translocation should be treated differently from others. Patients with extra copies of MALT1 could be initially treated with H. pylori eradication,similar to patients without t(11;18) translocation or extra copies of MALT1.

Primary mucosa-associated lymphoid tissue lymphoma of the liver: A report of two cases and review of the literature

Mucosa-associated lymphoid tissue(MALT) lymphoma of the liver is a very rare condition and thus the diag-nosis may be challeng-ing-. The clinical presentation is usually variable, rang-ing- from minimal clinical symptoms to severe end stag-e liver disease. In this paper, we describe the clinicopatholog-ic finding-s in two cases of primary hepatic MALT lymphoma. One case is an 80-year-old female with no underlying- chronic liver disease and the second case is a 30-year-old female with autoimmune hepatitis complicated by MALT lymphoma. In both specimens, there was diffuse infiltration of atypical B-lymphocytes that were positive for CD20 and CD79 a, but neg-ative for CD5, CD43 and CD10. There were occasional lymphoepithelial lesions involving- the hepatocytes or bile ducts. Polymerase chain reaction analysis showed monoclonal immunog-lobulin heavy chain g-ene rearrang-ement in both cases. The first case was treated with surg-ery but developed pulmonary recurrence a year after complete resection but went into remission following- treatment with rituximab. A second recurrence occurred in the rig-ht parotid g-land 7 years later, which was treated with idelalisib. The second case was effectively treated with rituximab. To our knowledg-e, the second case is the first reported case linked to autoimmune hepatitis.

Colonic mucosa-associated lymphoid tissue lymphoma identified by chromoendoscopy

Colonic mucosa-associated lymphoid tissue (MALT) lymphomas are a rare occurrence and the definitive treatment has not been established. Solitary or multiple, elevated or polypoid lesions are the usual appearances of MALT lymphoma in the large intestine and sometimes the surface may reveal abnormal vascularity. Herein, we report a case of MALT lymphoma and review the relevant literature. Upon colonoscopy, a suspected pathologic lesion was observed in the proximal transverse colon. The lesion could be distinguished more prominently after using narrow-band imaging mode and indigo carmine-dye spraying chromoendoscopy. Histopathologic examination of this biopsy specimen revealed lymphoepithelial lesions with diffuse proliferation of atypical lymphoid cells effacing the glandular architecture and centrocyte-like cells infiltrating the lamina propria. Immunohistochemical analyses showed that tumor cells were positive for CD20 and Bcl-2e, and negative for CD10, CD23, and Bcl-6. According to Ann-Arbor staging system, the patient had stage IIE. A partial colectomy with dissection of the paracolic lymph nodes was performed. Until now, there is no recurrence of lymphoma at follow-up.

Primary renal mucosa-associated lymphoid tissue lymphoma, 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.

Mucosa-associated lymphoid tissue lymphoma of the transverse colon: A case report

We herein present a case of a 75-year-old female with mucosa-associated lymphoid tissue （MALT） lymphoma of the transverse colon with the stage IE （Ann Arbor classification）. Colonoscopy revealed the tumor＇s appearance as a IIa plus Ⅱ c-like early colon cancer as defined according to the macroscopic classification of the Japanese Research Society for Cancer of Colon, Rectum and Anus, measuring less than 2 cm in diameter. Histologically, the tumor was diagnosed as MALT lymphoma because of the presence of lymphoepithelial lesions consisting of diffuse proliferation of atypical lymphocytes and glandular destruction. The majority of these lymphocytes immunohistochemically stained for the B-lymphocyte marker. The patient first underwent H pylori eradication therapy with Lansap. However, the tumor size gradually increased over the next 4 mo and the patient eventually underwent surgical resection. The operative procedure included a partial colectomy with dissection of the paracolic lymph nodes. The tumor measured 45 mm × 30 mm in diameter and histological examination showed that the lymphoma cells had infiltrated the muscle layer of the colon without nodal involvement. The patient has had no recurrence postoperatively without any chemotherapy.