title: Non-Hodgkin's lymphoma involving the breast.
abstract: Breast involvement by non-Hodgkin's lymphoma is rare. Differences between primary and secondary breast lymphoma have been reported, and a relationship between primary breast lymphoma and lymphomas of mucosa-associated lymphoid tissue has been suggested. We reviewed 61 cases of breast lymphoma (41 primary, 13 secondary, and 7 unclear) that included 28 right-sided masses at presentation, 17 left-sided, 12 bilateral, and 4 in which the side was not known. A subgroup of bilateral breast lymphomas was identified that occurred in young women, four of which were pregnant or postpartum. A high incidence of intermediate- and high-grade lymphomas were present in both cases of primary and secondary lymphomas as was a high frequency of B-cell phenotype. Additional immunohistochemical studies failed to demonstrate evidence of marginal or mantle cell differentiation in seven of eight cases studied. Lymphoepithelial lesions were identified in a majority of cases, including 67% of primary and 64% of secondary lymphomas. This study failed to demonstrate a morphologic difference between primary or secondary lymphomas of the breast and suggests that breast lymphomas differ from other extranodal lymphomas in that the latter are frequently low grade.
authors.affiliation: Division of Pathology, City of Hope National Medical Center, Duarte, California.
authors.forename: D A
authors.initials: DA
authors.lastname: Arber
authors.forename: J F
authors.initials: JF
authors.lastname: Simpson
authors.forename: L M
authors.initials: LM
authors.lastname: Weiss
authors.forename: H
authors.initials: H
authors.lastname: Rappaport
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology* / Q000556:secondary; D005260:Female; D006801:Humans; D016393:Lymphoma, B-Cell / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000473:pathology