Gastric mucosa-associated lymphoid tissue lymphoma is one of the more common types of primary gastric lymphoma. It is characterized by low malignancy, slow progression, and is closely related to H. pylori infection, and is the only malignant tumor that can be treated with antibiotics alone to obtain complete remission. It can develop in both men and women, slightly more in men, commonly in young adults, and the incidence has been gradually increasing in recent years.
I. Etiology and pathogenesis
The etiology and pathogenesis of lymphoma are not fully understood, but the bacterial and viral theories have been emphasized. Among them, the relationship between HP and gastric MALT lymphoma as well as EBV and intestinal NKT cell lymphoma, Burkitt lymphoma and AIDS-associated lymphoma has attracted a lot of attention.
In the general population, the prevalence of HP infection can be as high as 60-90%, and the vast majority of patients with gastritis associated with HP infection do not develop gastric MALT lymphoma. Therefore other factors such as environmental factors, microorganisms and host genetics may be jointly involved in the development of the disease. It is now believed that the immune function of the patient is closely related to the development of gastric lymphoma. The development of lymphoma is associated with the proliferation and differentiation of various immune cells produced by lymphoid tissue in response to the immune response. Patients with immunodeficiency, post-transplantation patients, patients with dry syndrome, and patients with inflammatory bowel disease have a higher chance of developing lymphoma than the general population.
II. Clinical manifestations
Gastric MALT lymphoma usually presents with non-specific GI symptoms such as abdominal pain, bleeding, nausea, vomiting and weight loss. These symptoms can also be seen in other GI diseases such as gastric cancer and gastric ulcer. Because the pathological pattern of the disease is difficult to distinguish from lymphocytic gastritis, most patients may have a prolonged course for several years, with recurrent upper abdominal discomfort and even repeated gastrointestinal bleeding.
Physical examination may reveal anemia, abdominal mass, epigastric pain, and superficial lymph node enlargement.
III. Complications
1. Bleeding: It is the most common complication of gastric MALT lymphoma. Even some patients had to take emergency surgery due to hemorrhagic shock caused by gastrointestinal hemorrhage. During the process of HP eradication and follow-up observation, patients may also have recurrent black stools due to poor therapeutic effect.
2. Obstruction: The lesions of gastric MALT lymphoma are often extensive and can extend from the gastric body and sinus to the descending duodenum, leading to pyloric and duodenal stenosis and symptoms of gastrointestinal obstruction. At this time, the effect of oral anti-HP drugs is poor, and intravenous acid suppression and antibiotics can be used.
3, perforation: due to the low malignancy and slow progression of the disease, complications of perforation are extremely rare.
4. High malignant transformation: transformation of gastric MALT lymphoma to diffuse large B-cell lymphoma is the most common form of malignant transformation of gastric lymphoma. 15% of gastric diffuse large B-cell lymphoma can be seen in the form of residual MALT lymphoma. Progressive progression from initially low-grade malignant gastric MALT lymphoma to highly malignant gastric diffuse large B-cell lymphoma can also be observed in some patients who are resistant to antibiotics during the course of anti-HP therapy.
IV. Diagnosis
1.Gastroscopy.
2.Ultrasound endoscopy.
3.Testing of H. pylori.
4.CT.
5.Bone marrow biopsy.
6.Pathology examination.
V. Prognosis
The prognosis of gastric MALT lymphoma is better than that of other types of gastric lymphoma and gastric cancer, and the 5-year survival rate can reach more than 80% regardless of the treatment method. However, during the treatment process, appropriate methods should be actively selected to strive for complete remission of patients at an early stage, reduce the incidence of complications and improve the quality of survival.