Primary breast lymphoma of Mucosa Associated Lymphoid Tissue: report of one case

A 46-year-old patient was referred for a right mammary nodule associated wi th a chronic mastopathy. Cytological examination suggested an inflammatory process but frozen sections concluded to carcinoma with lymphoid stroma. Hi stological examination found characteristic features of MALT lymphoma. reac tive lymphoid follicles, lymphoplasmocytoid lymphoid proliferation and lymp hoepithelial lesions. Immunohistochemistry and in situ hybridation revealed a monotypic IgGk immunoglobulin. Molecular biology techniques found a rear rangement of IgH locus. Lymphocytic perigalactophoritis was found in the re maining breast tissue. After 33 months, no tumoral recurrence occurred. Primary MALT lymphoma of the breast is exceptional and its histogenesis is unclear. The role of pre-existent inflammatory lesions in the genesis of th is tumour is not established. Our observation illustrates the diagnostic difficulty and the usefulness of complementary techniques in this diagnosis. The existence of inflammation close to tumour is interesting to emphasize.