Rapidly growing primary gastric B-cell lymphoma after eradication of Helicobacter pylori.

Helicobacter pylori (H. pylori) infection plays a decisive role in primary gastric B-cell lymphoma especially of mucosa-associated lymphoid tissue (MALT)-type. We treated a 47-year-old male patient with primary gastric B-cell lymphoma associated with H. pylori infection. Although antibiotic therapy for eradication of H. pylori caused great improvement in the low-grade MALT lymphoma-like lesion, the small areas of high-grade lesion rapidly formed a new bulky mass in only 8 weeks. This suggests that eradication of H. pylori is not effective for high-grade lymphoma.