case_images: PMC3111039_01
case_images: Serum immunofixation electrophoresis showed a dense abnormal zone of restriction in the IgM lane and in the lambda light chain lane.
case_images: kjlm-31-18-g001.jpg
case_images: PMC3111039_01_kjlm-31-18-g001.jpg
case_images: F1
case_images: Serum immunofixation electrophoresis demonstrated monoclonal gammopathy of the IgM lambda type (Fig. 1).
case_images: Microscopic features of the small intestinal mucosa-associated lymphoid tissue lymphoma. (A) The tumor cells of the marginal zone surround the reactive follicles and diffusely infiltrate the mucosa (hematoxylin and eosin stain, x100). (B) A lymphoepithelial lesion showing destruction of the intestinal crypts by tumor cells (arrows) (hematoxylin and eosin stain, x400). (C) Plasma cells with eccentric nuclei are admixed with small lymphocytes (hematoxylin and eosin stain, x400). (D) Plasma cells are highlighted (brown) by immunohistochemical staining for CD38 (Immunohistochemistry, x400).
case_images: kjlm-31-18-g002.jpg
case_images: PMC3111039_01_kjlm-31-18-g002.jpg
case_images: F2
case_images: Histologic examination revealed the MZ tumor cells infiltrating around the reactive follicles and disseminating to the small bowel mucosa (Fig. 2A). The intestinal crypt epithelium was often invaded and destroyed by these tumor cells, leading to the formation of the lymphoepithelial lesion (Fig. 2B). Plasmacytic differentiation was observed, which was verified by immunohistochemistry for CD38 (Fig. 2C, D).
case_images: Findings of peripheral blood smear and bone marrow study. (A) The peripheral blood smear shows a plasmacytoid lymphocyte (Wright stain, x1,000). (B) The bone marrow aspirate contains 2.1% plasma cells (Wright stain, x1,000). (C) Bone marrow biopsy showing interstitial infiltration of mature lymphocytes (hematoxylin and eosin stain, x400).
case_images: kjlm-31-18-g003.jpg
case_images: PMC3111039_01_kjlm-31-18-g003.jpg
case_images: F3
case_images: The bone marrow aspirate showed 20% cellularity and 2.1% of plasma cells (Fig. 3B). Bone marrow biopsy revealed focal infiltration of the neoplastic lymphoid cells, which showed a morphologic spectrum, including small lymphocytes with inconspicuous nucleoli and plasmacytoid lymphocytes (Fig. 3C).