Lymphoproliferative Diseases of the Gut

The gastrointestinal tract is the most common extranodal site of involvement by lymphoma, with B-cell tumors outnumbering T-cell tumors by a wide margin. Diffuse large B-cell lymphoma is the most common lymphoid neoplasm involving the gastrointestinal tract; but a variety of other B- and T-cell neoplasms occur in the gastrointestinal organs, often with characteristic associations and/or manifestations. Although the diagnosis of gastrointestinal lymphomas can sometimes seem daunting to general pathologists, a knowledge of the most commonly encountered entities, in combination with a reasoned and pragmatic approach to the diagnostic workup, makes it possible to approach most cases with confidence.