Clinical And Pathologic Study Of Gastric MALT Lymphoma & The Expression And Significance Of PTEN, PI3K And PAkt

Objective To summarize the clinical,endoscopic and pathologic characteristics of 32 patients with gastric mucosa-associated lymphoid tissue(MALT)lymphoma.To investigate the treatment strategies of the gastric MALT lymphoma.To study the expression and significance of phosphatase and tension homology deleted on chromosome ten(PTEN),phosphatidylinositol-3-kinase(PI3K),serine/threonine protein kinase B(Akt)in gastric MALT lymphoma and analyze their relationship.Methods Clinical and other related materials of 32 patients with gastric MALT lymphoma diagnosed pathologically were retrospectively analyzed.Their pathologic sections were detected for PTEN,PI3K and Akt proteins by immunohistochemical staining.Results1.32 patients with gastric MALT lymphoma had a median age of 63.0 years.The male to female ratio was about 1:1.13.The common symptoms were upper abdominal pain,abdominal distension,acid regurgitation,vomiting and so on. Some of them were admitted for gastrointestinal hemorrhage.2.Under endoscopy,about 40.63%lesions were observed in gastric antrum,which was the most common site.The appearances of gastric MALT lymphoma were manifold,and the main pathological changes were upheaval type and ulcer type. The lymphoma was made definite so difficult that 25.00%cases could be diagnosed by endoscopy correctly at the first time.3.All the gastric MALT lymphoma stemmed from B lymphocyte.Markers such as CD45RO,CD20,EMA,LCA and so on were detected for pathologic diagnosis frequently.According to Ann Arbor staging system,4 cases belonged to stageⅠE, 9 cases belonged to stageⅡE,14 cases and 5 cases were at stageⅢand stageⅣrespectively.4.Helicobacter pylori infection was detected in 22 cases(88.00%),15 cases (46.88%)received H.pylori eradication therapy.Among 32 cases,20(62.50%) accepted surgery,surgery combined with chemotherapy were exerted on 13 patients,2 cases were treated with chemotherapy solely.3 patients achieved histological complete remission.5.The expression rate of PTEN in gastric MALT lymphoma was 31.25%,while the expression rate of PI3K and pAkt was 75.00%and 71.88%respectively.6.In gastric MALT lymphoma,the expression of PTEN was negatively correlated with that of PI3K(r_s=-0.896,P＜0.001).The expression of PTEN was also negatively correlated with that of pAkt(r_s=-0.840,P＜0.001).The expression of PI3K was positively correlated with that of pAkt(r_s=0.975,P＜0.001).Conclusions1.We should attach importance to the clinical,endoscopic and pathologic features of gastric MALT lymphoma.The clinical manifestations showed nonspecific. Patients who suffered from upper abdominal pain and gastrointestinal hemorrhage might be diagnosed as gastric lymphoma.2.Gastric MALT lymphoma was often detected at gastric antrum.Endoscopy could help find out the early focus,multiple biopsies could raise the rate of diagnosis.3.As for those hard to be diagnosed definitely,B and T cellular markers could be detected by immunohistochemical assay.4.H.pylori played an important role in pathogenesis of gastric MALT lymphoma. H.pylori eradication should be the first choice to treat gastric MALT lymphoma at early stage.In the past,surgery was the major strategy in treating gastric MALT lymphoma.However,H.pylori eradication has shown a good curative effect nowadays.As for the adaptive schemes,H.pylori infection,pathologic conditions and many other factors should be concerned.5.In gastric MALT lymphoma,expression of the encoding products of anti-oncogene PTEN was down-regulation,while the expressions of PI3K and pAkt were up-regulation.Moreover,the expression of PTEN was negatively correlated with that of PI3K and pAkt.6.These data suggest that PTEN may play an important role in pathogenesis of gastric MALT lymphoma.The abnormal activation of gastric MALT lymphoma correlated with its occurrence and development and it provided a potential therapeutic target.