Immunoproliferative disease of the gastrointestinal tract: a report of five cases.

: Five patients with immunoproliferative disease of the gastrointestinal tract are presented. The main pathological feature was dense diffuse lymphoplasmacytic and immunoblastic infiltration of the mucosa and submucosa, of the proximal small bowel in 3 cases and the stomach in 2. Four of the five patients had concomitant immunoblastic sarcoma. The clinical presentation and pathological findings are compared and contrasted with those of "Mediterranean abdominal lymphoma" and alpha chain disease, and the possible role of ethnogeographical and environmental factors in the pathogenesis are discussed.