title: Malignant lymphoma of mucosa-associated lymphoid tissue arising in the thymus of a patient with Sjögren's syndrome. A morphologic, phenotypic, and genotypic study.
abstract: A 59-year-old woman with Sjögren's syndrome had an anterior mediastinal tumor. The tumor had epithelium-lined thymic cysts. Histologically, centrocyte-like (CCL) cells were present as clusters intermingling with small lymphocytes and plasma cells, invaded the epithelium, and formed characteristic lymphoepithelial lesions; the tumor was identified as malignant lymphoma arising in mucosa-associated lymphoid tissue (MALT). Within the tumor, trapped Hassall's corpuscles were recognized. Immunohistochemical staining demonstrated monotypic cytoplasmic kappa light chains in a small portion of the CCL cells. Furthermore, Southern blot hybridization studies showed rearrangements of immunoglobulin heavy chain, immunoglobulin kappa light chain, and T-cell receptor beta genes. The findings are consistent with thymic low-grade B-cell MALT lymphoma.
authors.affiliation: Department of Pathology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Takagi
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: K
authors.initials: K
authors.lastname: Kunishima
authors.forename: I
authors.initials: I
authors.lastname: Takagi
authors.forename: M
authors.initials: M
authors.lastname: Suyama
authors.forename: M
authors.initials: M
authors.lastname: Shinoda
authors.forename: T
authors.initials: T
authors.lastname: Sugiura
authors.forename: A
authors.initials: A
authors.lastname: Oyama
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
mesh_terms: D003593:Cytoplasm / Q000648:ultrastructure; D005260:Female; D015322:Gene Rearrangement, B-Lymphocyte / Q000235:genetics; D005838:Genotype; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007147:Immunoglobulin Light Chains / Q000032:analysis; D007145:Immunoglobulin kappa-Chains / Q000032:analysis; D008221:Lymphoid Tissue / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000235:genetics* / Q000473:pathology*; D008854:Microscopy, Electron; D008875:Middle Aged; D009092:Mucous Membrane / Q000473:pathology; D015388:Organelles / Q000648:ultrastructure; D010641:Phenotype; D012859:Sjogren's Syndrome / Q000235:genetics / Q000473:pathology*; D013953:Thymus Neoplasms / Q000235:genetics* / Q000473:pathology*
chemical_list: D007070:Immunoglobulin A; D007147:Immunoglobulin Light Chains; D007145:Immunoglobulin kappa-Chains