Simultaneous primary gastric and duodenal MALT lymphoma presenting with gastrointestinal bleeding.

The gastrointestinal tract, particularly the stomach, is the most common site of mucosa-associated lymphoid tissue lymphoma (MALToma). Many studies describe primary MALT lymphoma arising from the gastric mucosa, especially in association with Helicobacter pylori infection. On the contrary, primary MALT duodenal lymphoma is a very rare neoplasm. We report a case of a patient with gastrointestinal bleeding in whom primary gastric and duodenal MALT lymphoma were occurred simultaneously.