Evaluating the Survival Impact of Different Treatment Modalities in Gastric Marginal Zone Lymphoma Based on Tumor Stage: A SEER Database Analysis
Authors: Bangolo Ayrton I , Zhang Lili , Nagesh Vignesh K , Ip Andrew , Amoozgar Behzad 
Published: December 2024

Introduction
Gastric marginal zone lymphoma (GMZL) is a distinct subtype of non-Hodgkin lymphoma characterized by its indolent nature and primary manifestation in the stomach. The therapeutic approach and subsequent survival outcomes can vary significantly based on the stage at diagnosis and the treatment modality used. GMZL often presents a complex treatment challenge due to its varied clinical manifestations. This retrospective study examines the impact of different treatment approaches on the survival of GMZL across various stages: localized, locally advanced, and advanced. The treatment approaches considered are no treatment, radiation, surgery, and chemotherapy.
Methods
We analyzed data from the SEER database for patients diagnosed with GMZL between 2010 and 2020. The patient cohort included 1,046 individuals with the following characteristics: 541 females (51.72%) and 505 males (48.28%); age distribution of 0-39 years (3.73%), 40-59 years (30.50%), 60-79 years (54.11%), and 80+ years (11.66%); Popuation race distribution were Non-Hispanic white (N=714, 68.26%), Non-Hispanic Black (N=106, 10.13%), Hispanic (N=116, 11.09%) and other races (N=110, 10.52%).
Staging distribution included localized GMZL (N=905, 86.52%), regional GMZL (N=95, 9.08%), and distant GMZL (N=46, 4.4%). Kaplan-Meier survival estimates were generated for four treatment approaches: no treatment, radiation, surgery, and chemotherapy. Tumor stages were categorized as localized, locally advanced, and advanced.
Results
Implementing Kaplan-Meier survival estimates for localized GMZL during the 150-month follow-up surgery resulted in high initial survival but with a significant drop around 50 months while stabilizing at 75 months of follow-up. For radiation, we experienced a gradual decline, with survival stabilizing around 50% at approximately 100 months. For locally advanced GMZL, only radiation showed sharp declines initially, with survival stabilizing at approximately 50% around 100 months. Other modalities did not show any drop. For advanced GMZL, the radiation approach showed sharp declines initially, with survival stabilizing at approximately 50% around 100 months. On the other hand, the surgical approach showed consistently high survival rates, with a significant drop occurring after 100 months.
When we compared all modalities with no treatment approach regardless of staging, statistical regression analysis showed a coefficient of 0.411 for radiation (p-value 0.001), 0.264 for surgery (p-value=0.006), and 0.519 for systemic therapy (p-value=0.079).
Analyzing survival probability over time for each stage using the Kaplan-Meier curve, we found that surgery has the highest survival probabilities for localized disease at all time points compared to other treatments (P&lt;0.05). For locally advanced diseases, both surgery and systemic therapy showed better survival proportions and less significant differences, suggesting they might be more effective (p-value &lt;0.05 in all comparisons). The same pattern was seen for advanced disease with surgery, and systemic showed significant differences when compared with other treatments (p-value &lt;0.05 in all comparisons).
Conclusion
The survival outcomes for GMZL patients highlight the importance of tailored treatment strategies. Surgery appears to be superior in localized diseases, while both surgical approach and systemic therapy appear to offer the most significant survival benefit in locally advanced and advanced stages. These findings emphasize the need for early detection and the selection of appropriate treatment modalities to optimize patient outcomes. Further research is necessary to refine these therapeutic approaches and enhance survival rates for GMZL patients.