Primary upper small-intestinal lymphoma and alpha-chain disease. Report of 10 cases emphasizing pathological aspects.

Ten cases of primary upper small-intestinal lymphoma associated with alpha-chain protein in serum were discovered in a prospective study of the sera of patients with immunoproliferative small-intestinal disease (IPSID). Patients were mostly young males presenting with abdominal pain, weight loss, and diarrhea and showing laboratory evidence of carbohydrate, fat, and vitamin B12 malabsorption and hypoalbuminemia. The more frequently encountered pathologic abnormality was a diffusely nodular jejunal mucosa produced by a plasmacytic infiltrate of variable cell maturity involving a varible depth of small bowel wall with or without involvement of the mesenteric or para-aortic-lymph node complex and, in one instance, the liver. A less frequent picture included circumferential ulcerative and constrictive transmural tumors of the upper small intestine produced by a malignant lymphoma with involvement of abdominal lymph nodes. Small-intestinal surface epithelial abnormalities, a dense mantle of mature plasma cells overlying the lymphoma, a pronounced follicular lymphoid hyperplasia adjacent to and at distances from the lymphoma were other features of note in our IPSID cases associated with alpha-chain protein.