Extranodal lymphoplasmacytoid lymphoma (immunocytoma) presenting as small intestinal obstruction - A case report and review of the literature

A 57-year-old woman presented with intermittent symptoms of intestinal obst ruction. Workup provided nondiagnostic radiologic studies. An exploratory l aparotomy revealed a segmental dilatation in the proximal ileum, which show ed diffuse thickening of the intestinal wall. Microscopic examination of th e affected area disclosed a diffuse transmural infiltrate composed of small lymphocytes, mature plasma cells, and lymphoplasmacytoid cells in differen t stages of maturation associated with extracellular periodic acid-Schiff-p ositive material. In addition, serum protein electrophoresis showed a monoc lonal immunoglobulin M kappa paraprotein. Postoperative workup did not demo nstrate evidence of systemic involvement. The morphologic features and immu nohistochemical and molecular analyses were consistent with lymphoplasmacyt oid lymphoma (immunocytoma). We report an unusual case of primary extranoda l immunocytoma involving the small intestine and discuss its clinicopatholo gic features.