Gastrointestinal (GI) lymphoma encompasses a heterogeneous group of neoplasms that have a common lymphoid origin but variable pathologic and imaging features. Extranodal marginal zone B-cell lymphoma (ENMZL) and diffuse large B-cell lymphoma (DLBCL) are the most common. ENMZL usually occurs in the stomach, where it is associated with chronic infection by Helicobacter pylori, and is typically a superficial spreading lesion that causes mucosal nodularity or ulceration and mild wall thickening. DLBCL may arise de novo or from transformation of ENMZL or other low-grade lymphomas. This form of lymphoma produces extensive wall thickening or a bulky mass, but obstruction is uncommon. Mantle cell lymphoma is the classic cause of lymphomatous polyposis, but multiple polyps or nodules can also be seen with ENMZL and follicular lymphoma. Burkitt lymphoma is usually characterized by an ileocecal mass or wall thickening in the terminal ileum in young children, often in the setting of widespread disease. Primary GI Hodgkin lymphoma, which is rare, may be manifested by a variety of findings, though stenosis is more common than with non-Hodgkin lymphoma. Enteropathy-associated T-cell lymphoma is frequently associated with celiac disease and is characterized by wall thickening, ulceration, and even perforation of the jejunum. Accurate radiologic diagnosis of GI lymphoma requires a multifactorial approach based on the clinical findings, site of involvement, imaging findings, and associated complications.
©RSNA, 2014.