Clinical features and temporal trends in H. pylori negative gastric maltoma.

Background: Mucosa-Associated Lymphoid Tissue (MALT) lymphoma or MALToma is a type of non-Hodgkin lymphoma arising in the gastric mucosa that has largely been associated with Helicobacter pylori (H. pylori) infection. However, less than 10% of gastric MALTomas can occur with a negative H. pylori status, and the disease seems to have a different course.

Patients And Methods: Patients diagnosed with MALToma from 2000 to 2021 were included in the study. H. pylori-negative (HPN) status was confirmed when patients had at least 2 negative tests among the following: urea breath test, rapid urease test, serological test, or histology. The patients were divided into H. pylori positive (HPP) and HPN groups.

Results: The final analysis included 52 gastric MALToma patients, 25 (48.1 %) were HPN. Demographics and disease stages were comparable between the two groups, although a higher prevalence of HPN cases emerged in patients diagnosed from 2011 to 2021 compared to the 2000-2010 period (55.3 % vs. 28.6 %, p = 0.09). All patients in the HPP group received eradication therapy (ET) compared to only 40 % in the HPN group. ET success in the stage 1 HPN group was 25 % compared to 78.6 % in the HPP group (p = 0.03). More patients in the HPN group received chemo and/or radiotherapy compared to the HPP (86.4 % vs 57.1 %, p = 0.033). Treatment outcomes were similar between both groups. Comparing stage 1 MALToma patients who responded to ET versus non-responders revealed that responders were more likely to be HPP (76.8 % vs. 33.3 %, p = 0.026) and diagnosed in the earlier period (2000-2010, p = 0.048).

Conclusion: HPN MALToma patients were similar to HPP patients in clinical features. However, there was an increase in diagnosis of HPN MALToma and a decrease in response to ET in more recent years.