Stomach is the most common site of primary extranodal lymphoma. Mucosa-associated lymphoid tissue (MALT) lymphoma is a unique type of extranodal lymphoma which is associated with Helicobacter pylori (H. pylori). The development of low-grade MALT lymphoma of stomach is dependent on H. pylori. A transformed clone carrying the translocation t(11;18)(q21;q21) forms a MALT lymphoma, the growth of which is independent of H. pylori and will not respond to bacterial eradication. And inactivation of the tumor suppressor genes, p53 can lead to high-grade transformation. Endoscopic ultrasound (EUS) is essential to document the extent of disease and is superior to CT scan in the detection of spread to perigastric lymph nodes and follow-up EUS may determine the response to therapy and detect the relapse in early phase. Lesions that are confined to the mucosa or submucosa of gastric wall can be successfully treated with H. pylori eradication. Those low-grade MALT lymphomas that are not H. pylori positive or do not respond to antibiotic therapy can be treated with surgery, radiation, or chemotherapy. Follow-up is critical in all patients who have been treated with H. pylori eradication and consists of multiple endoscopic biopsies and EUS.
Helicobacter Infections/complications ; Helicobacter pylori ; Humans ; *Lymphoma, B-Cell, Marginal Zone/microbiology/pathology ; Stomach Diseases/complications ; *Stomach Neoplasms/microbiology/pathology

Both lymphocytic gastritis and gastric mucosa associated lymphoid tissue (MALT) lymphoma are associated with Helicobacter pylori (H. pylori) infection. However, this association has not been fully elucidated. We report two cases of lymphocytic gastritis in 57-year-old male and 47-year-old female patients which were diagnosed after the H. pylori eradication to treat gastric MALT lymphoma. MALT lymphoma was successfully treated in case 1, but residual MALT lymphoma remained in case 2. During the follow-up endoscopic examinations, several elevated erosions in case 1 and irregular mucosal atrophy in case 2 were newly detected. Biopsy specimens showed marked infiltration of lymphocytes in the surface epithelium (56.6+/-15.9 intraepithelial lymphocytes (IELs)/100 epithelial cells in case 1 and 40.5+/-9.3 IELs/100 epithelial cells in case 2), which were exclusively CD8-positive T lymphocytes. These findings suggest that H. pylori infection may cause a monoclonal proliferation of B lymphocytes, leading to MALT lymphoma as well as polyclonal proliferation of T lymphocytes which subsequently infiltrated into the surface epithelium as a host immune reaction, resulting in lymphocytic gastritis.
Gastric Mucosa/*pathology ; Gastritis/*complications/microbiology/pathology ; Helicobacter Infections/*complications ; *Helicobacter pylori ; Humans ; Lymphocytes/*pathology ; Lymphoma, B-Cell, Marginal Zone/*complications/microbiology ; Male ; Middle Aged ; Stomach Neoplasms/*complications

It is often difficult to differentiate gastric mucosa-associated lymphoid tissue (MALT) lymphoma from Helicobacter pylori-associated follicular gastritis, and thus, it becomes unclear how to manage these diseases. This study aimed to explore the management strategy for and the long-term outcomes of suspicious gastric MALT lymphoma detected by forceps biopsy during screening upper endoscopy. Between October 2003 and May 2013, consecutive subjects who were diagnosed with suspicious gastric MALT lymphomas by screening endoscopy in a health checkup program in Korea were retrospectively enrolled. Suspicious MALT lymphoma was defined as a Wotherspoon score of 3 or 4 upon pathological evaluation of the biopsy specimen. Of 105,164 subjects who underwent screening endoscopies, 49 patients with suspicious MALT lymphomas who underwent subsequent endoscopy were enrolled. Eight patients received a subsequent endoscopy without H. pylori eradication (subsequent endoscopy only group), and 41 patients received H. pylori eradication first followed by endoscopy (eradication first group). MALT lymphoma development was significantly lower in the eradication first group (2/41, 4.9%) than in the subsequent endoscopy only group (3/8, 37.5%, P = 0.026). Notably, among 35 patients with successful H. pylori eradication, there was only one MALT lymphoma patient (2.9%) in whom complete remission was achieved, and there was no recurrence during a median 45 months of endoscopic follow-up. H. pylori eradication with subsequent endoscopy would be a practical management option for suspicious MALT lymphoma detected in a forceps biopsy specimen obtained during screening upper endoscopy.
Adult ; Aged ; Anti-Bacterial Agents/therapeutic use ; Biopsy ; Female ; Follow-Up Studies ; Gastric Mucosa/*pathology ; Gastritis/diagnosis/etiology/microbiology ; Gastroscopy ; Helicobacter Infections/complications/*diagnosis/drug therapy ; Humans ; Lymphoma, B-Cell, Marginal Zone/complications/*diagnosis/pathology ; Male ; Middle Aged ; Republic of Korea ; Retrospective Studies