Mantle cell lymphoma presenting as multiple lymphomatous polyposis of the gastrointestinal tract

The gastrointestinal (GI) tract is the most common extranodal site affected by lymphoma, accounting for 5–20% of all cases.1 The incidence and location of primary GI lymphoma varies around the world. Overall, the most commonly involved sites are the stomach followed by the small bowel and ileocecal region.2 Concerning histological subtypes, mucosa-associated lymphoid tissue lymphoma is more common in the stomach, mantle cell lymphoma (MCL) in the terminal ileum, jejunum and colon, enteropathy-associated T-cell lymphoma in the jejunum, and follicular lymphoma in the duodenum with a geographic variation in its distribution.3 MCL is a rare and distinct subtype of B-cell neoplasm, comprising approximately 6–9% of all malignant lymphoma in Western Europe, with an incidence of 1–2 cases/105 people/year.4 Endoscopic features of GI lymphomas are heterogeneous, encompassing ulcers, erosions, polyps and so on. GI polyposis