Role of 18F-FDG PET Scans in Patients with Helicobacter pylori-Infected Gastric Low-Grade MALT Lymphoma

Background/Aims: Endoscopic ultrasound (EUS) plays a crucial role in the assessment and treatment of low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma; however, interobserver variation, inadequate accuracy in judging the depth of tumor invasion, and histological heterogeneity of the tumor can limit its role. Thus, we have assessed the role of 18F-FDG PET scans in the management of Helicobacter pylori-infected gastric MALT lymphoma. Methods: Eighteen patients with H. pylori-infected low-grade gastric MALT lymphoma underwent an 18F-FDG PET scan prior to receiving H. pylori eradication therapy. We analyzed these patients` clinicopathologic data and measured the baseline and change in the metabolic activity of the tumor using standardized uptake values (SUVs). Results: Two patients failed to achieve complete remission of the low-grade gastric MALT lymphoma after successful H. pylori eradication. The baseline SUVs were significantly higher in these patients compared to successfully treated patients, 13.35±0.07 vs 2.98±0.93, respectively (n=2 vs n=16, p