EXTRA NODAL MARGINAL ZONE LYMPHOMA OF BREAST AND STOMACH

Case History

The patient is an 81-year-old woman with a history of extra nodal marginal zone B cell lymphoma dating back to October, 2008. The patient originally presented with bilateral breast nodules which were biopsied and the diagnosis of extra nodal marginal zone B-cell lymphoma was rendered. Consequently she developed upper GI symptoms prompting an upper endoscopic examination which revealed a healing gastric ulcer with atypical lymphoid cells consistent with extra nodal marginal zone B-cell lymphoma. The H. Pylori stain was positive at the time and the patient underwent treatment for H. Pylori. She did have a dramatic response to H. Pylori treatment with almost complete resolution of her gastric ulcer and marked reduction in the size of the breast nodules. In early 2011, she was found to be iron deficient/guiac positive stool.  Another upper endoscopic examination ensued and biopsies were obtained.

Microscopic Findings

Biopsies from gastric body revealed a dense, monotonous lymphoid infiltrate involving the lamina propria and infiltrating through muscularis mucosa. Lymphoid cells were small to medium sized with irregular nuclei (centrocyte like cells). Lympho epithelial lesions were also identified. Immunoperoxidase stains for H. Pylori were negative. There was no evidence of transformation to high grade B-cell lymphoma. No benign lymphoid follicles were detected. No plasmacytic differentiation was identified.  Patient refused Rituxan therapy and is currently being treated for iron deficiency.

Diagnosis

RECURRENT MULTIFOCAL EXTRA NODAL MARGINAL ZONE LYMPHOMA OF MUCOSA ASSOCIATED LYMPHOID TISSUE (MALT LYMPHOMA)

Discussion

Marginal zone B-cell lymphomas are a group of low grade B-cell lymphomas that arise from the marginal zone of the secondary follicles. Depending on the site the International Lymphoma Study Group recommends three distinct subtypes, extra nodal marginal zone, or MALT lymphomas, splenic marginal zone lymphomas and nodal marginal zone lymphomas. MALT lymphomas account for 7-8% of all B-cell lymphomas. Most cases occur in adults with a median age of 61. Disease is localized for majority of the patients but multifocal lesions are present in 30-40% of patients. Bone marrow involvement is present in 20%. Prolonged chronic inflammation as a result of infection with H.Pylori, autoimmunity or other unknown stimuli is believed to represent a precursor lesion. The gastrointestinal tract is the most common site of MALT lymphoma comprising up to 50% of all cases. Stomach is the most common site of involvement (85%).  Lymphoma cells of MALT are CD20+, CD79a+, CD5-, CD10-, CD23-, CD43+/-. Chromosomal translocations associated with MALT lymphoma include t(11;18)(q21;q21), t(1;14)(p22;q32,t(14;18)(q32;q21and t(3;14(p14.1;q32).

MALT lymphomas have an indolent course and recur with frequency. Local treatment with radiation may be followed by prolonged disease free intervals.

References

1. WHO Classification of Tumors of Haematopoietic and Lymphoid Tissue. France: International Agency for Research on Cancer, 2008: 214-217.

2. Thieblemont, C.” Clinical and Management of Marginal Zone Lymphomas,”  Am. J. Soc. Hematology, 2005.

H&E stain; Low Power Magnification: dense lymphoid infiltrate with near total replacement of breast tissue
H&E stain; Medium Power Magnification: monotonous lymphoid infiltrate
H&E stain; High Power Magnification: small lymphocytes and scattered histiocytes
H&E stain; High Power Magnification: residual breast ducts and interstitial fibrosis
H&E stain; High Power Magnification: lymphoid cells, some with irregular nuclei (centrocyte-like cells)
H&E stain; High Power Magnification: small lymphocytes and scattered histiocytes
H&E stain; High Power Magnification: residual germinal center
H&E stain; High Power Magnification: lymphoepithelial lesion
H&E stain; High Power Magnification: gastric biopsy with dense lymphoid infiltrate
H&E stain; High Power Magnification: rare germinal centers surrounded by centrocyte like cells
H&E stain; High Power Magnification: atypical lymphoid cells
H&E stain; High Power Magnification: neoplastic lymphoid cells dissecting through muscularis mucosa
H&E stain; High Power Magnification: lymphoepithelial lesion
H&E stain; High Power Magnification: atypical lymphoid cells
H&E stain; Low Power Magnification: dense lymphoid infiltrate involving lamina propria
H&E stain; High Power Magnification: germinal centers replaced by neoplastic lymphoid cells