The most common extranodal lymphoma and accounts for about 30% of all primary extranodal lymphomas.
About half are of gastric origin and 30-40% occur in the small bowel.
Most are of B-cell lineage, with diffuse, large B-cell lymphoma being the most common histology.
In the middle east and Medit2242anean, primary small bowel lymphoma accounts for most cases.
H. Pylori infection may contribute to lymphoma involving the mucosa-associated lymphoid tissue of the stomach.
The Medit2242anean variety of small bowel lyhoma, also known as immunoproliferative small intestinal disease, may be manifested by abdominal pain, diarrhea, malabsorption, and weight loss.
Other small bowel lymphomas include enteropathy associated T-cell lymphoma associated with celiac disease, Burkitt’s lymphoma, and B cell lymphomas.
Most the GI lymphomas are associated with obstruction, perforation, or hemorrhage.