Clinical Analysis Of 20 Cases Gastrointestinal-tract Mucosa Associated Lymphoid Tissue

The concept of mucosa-associated lymphoid tissue (MALT)lymphoma was first proposed in 1983 by Isaacson and Wrigh.It is agreed an independent disease entity according to the new World Health Organization Classification of Lymphoid and Haematopoietic Tissues.Extranodal lymphomas of the MALT account for approximately 8%of all non-Hodgkin's lymphomas and comprises up to 50%of primary gastric lymphomas.The Gastrointestinal-tract MALToma is the most common extranodal lymphoma,and they are of B cell origin.The Gastrointestinal-tract MALToma belongs to the low rates of histologic lymphoma,with distinctive hisyology character,immune phenotype and genotype.Most of them are limited to local and progress slowly.The specific connection between its onset and Helicobacter pylori(Hp)and the lymphoma regression after anti-helicobacter therapy are noticed recently,arising great interest in science fields.Our team studied 20 cases of patients with gastrointestinal-tract MALToma in ShanDong Province Hospital in past ten years.To arise the physician notice and elevate the level of diagnoses and therapy,We retrospectively analyzed the clinical manifestations,laboratory examination and diagnostic and therapeutic modalities.In this project,our team studied 20 cases of patients with gastrointestinal-tract MALToma in ShanDong Province Hospital for the period from February 1998 to February 2008.The finding is elaborated as follow.(1)During the period of 1998-2008,764 cases were diagnosed NHL in ShanDong Province Hospital and 20 cases of gastrointestinal-tract MALToma were diagnosed according to the new classification neoplasms.The patients(8 men and 12 women)ranged in age from 31 to 78 with a median age of 61 and a ratio slightly male preponderance(male:female ratio 1.5:1).The sex ratio and episode age aren't in accordance with literate reported.This need be testified by big sample further.(2)Clinical data:In 13 cases of gastric MALToma,Presenting features of 9 cases primary gastric lymphomas are nonspecific,with abdominal pain,malaise of epigastrium,in appetence and inertia etc,resembling the symptoms of gastritis or peptic ulcer.Presenting primary feature of 2 cases are hematemesis,and the other 2 cases primary feature are presenting of hematochezia.In 7 cases of intestinal-tract MALToma,Presenting features of 5 cases are intestinal obstruction,Presenting primary feature of 2 cases are hematemesis,and the other 2 cases primary feature are presenting of hematochezia.(3)Etiology examine:The connection between gastric MALT lymphoma and H.pylori infection is well established recently.I propose H.pylori should be routinely examined in such patients later.(4)Laboratory examination:5 cases showed anemia,accounting for 25%of our data.Among them,4 cases showed microcyti-chypochromic anemia.Chronic blood loss from digestive tract is the common cause of anemia as others gastric tumors.Endoscopic evaluation:13 cases of gastric MALToma:Endoscopic evaluation showed 2 cases diagnosed gastritis,2 peptic ulcer,7 gastric cancer and 2 suspected gastric lymphoma.54.2%of them are misdiagnosed gastric cancer.7 cases of intestinal-tract MALToma:Endoscopic evaluation showed 3 cases diagnosed chronic mucous inflammation,2 benign intestinal-tract mucous proliferation,1 Crohn disease and 1 suspected intestinal-tract lymphoma.85.7%of them are misdiagnosed.This indicates we should elevate the cognition of its general configuration.(5)Pathological data:The specimen after operation showed most gastric MALTomas arise in the antrum and intestinal-tract MALTomas arise in the ileocecum.Macroscopically,the lymphoma infiltrated into mucosa,sub-mucosa,muscular layer and seroma or perigastric region diffusely or locally.According to Ann Arbor,14 cases presented with stageâ… E,5 with stageâ…¡1E and 1 with stageâ…¢E.The histologic features of low-grade gastric MALT lymphoma closely simulate those of the Peyer's patch.The lymphoma infiltrates around reactive follicles in the region corresponding to Peyer's patch marginal zone,spreading diffusely into the surrounding mucosa.The tumor cells may resemble folliclecenter centrocyte(centrocyte-like cells),small lymphocytes,or so-calledmonocytoid B cells.The tumor cell have small to medium-sized,moderately,irregular nuclei,resembling centrocyte.An important features of low-grade gastric MALT lymphoma is the presence of lymphoepithelial lesions formed by invasion of individual glands by aggregates of lymphoma cells.Plasmacytic differentiation is present in approximately one third of gastric MALToma.Sometimes there are moderate plasma cell.Immunohistochemically,all cases were CD20 positive,while CD45RO were negtive.This indicates the tumor cell is of B cell origin.(6)Therapy and prognosis:Most of gastric MALToma are limited to local.They Seldom disseminated and progress slowly.But the operation bring unnecessary body and mind pain and economic burden,and bringing slight or severe complication.It is generally accepted that the anti-helicobacter therapy can cure most patients.The low-dose local radiotherapy and chemotherapy also have very high remission rate in patients with gastric MALT lymphoma.So this should arise the physician and pathologist's notice,and we should redress the inertia of operation after the malignant disease diagnosed.If there are no effect after anti-helicobacter therapy or showing of chromosome dystopy or high stage rate,we should plan the colligate therapy,such as anti-helicobacter therapy,chemotherapy,radiotherapy and operation.As to intestinal-tract MALToma,the plan of treatment is to resect the primary focus and subsequently to clear the residuals via chemotherapy.Great progress on research of CD20 target-therapy has been made in recent years.The conclusion is that CD20 target-therapy is not only be able to improve the efficiency of chemotherapy,but also can decrease the incidence rate of sever infection by contrast with traditional chemotherapy.To sum up:(1)The pathogenesis mechanism of gastrointestinal-tract MALToma is complicated.The clinical presentation is nonspecific.So it is often misdiagnosed.The misdiagnosed rate of our data is nearly 54.2%and 85.7%.To avoid omission or misdiagnosis and delayed or inappropriate therapy,the physican and pathologist should elevate the cognition of g gastrointestinal-tract MALToma.(2)It is generally accepted that the anti-helicobactertherapy can cure most patients.The low-dose local radiotherapy and chemotherapy also have very high remission rate in patients with gastric MALToma.In our data,even in the early stage,the patient were all operated.There are no one record of anti-helicobacter therapy or low-dose local radiotherapy in our data.This isn't in accordance with today therapy evidently.No doubt,CD20 target-therapy, which can provide higher efficiency and fewer side effects during the whole process of chemotherapy,will blaze a new trail to treat the lymphoma of the human digestive tract.