title: True histiocytic lymphoma: histopathologic, immunophenotypic and genotypic analysis.
abstract: Five cases of true histiocytic lymphoma (THL) were analysed by immunophenotyping and immunoglobulin/T-cell receptor genotyping. These cases showed striking morphologic diversity but a strong degree of immunophenotypic homogeneity. The malignant cells reacted with multiple histiocytic markers including CD11c (Ki-M1, LeuM5), CD14, CD68 (Ki-M6) and Ki-M8; anti-HLA-DR and non-specific esterase staining was also found in all cases. The malignant cells did not express monoclonal immunoglobulin and did not react with the B- or T-cell monoclonal antibodies used except for those known to be cytoplasmically expressed in monocytes/histiocytes, such as CD4 and CD19; B- and T-cell staining was otherwise limited to background small lymphocytes. By genotypic analysis, three cases showed rearrangements: one with T beta, one with T beta and immunoglobulin heavy chain (JH) and one with both JH and light chain; the remaining two cases retained their immunoglobulin and T-cell receptor genes in germline configuration. The results not only suggest that certain subsets of the histiocyte/reticulum cell system may be capable of rearranging immunoglobulin or T beta genes while simultaneously expressing multiple histiocytic surface antigens but also demonstrate the necessity of using multiple histiocytic-specific monoclonal antibodies and cytochemical staining in diagnosing THL. Gene rearrangement studies must be interpreted in conjunction with immunophenotyping and morphology in the determination of cell lineage.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota Hospital and Clinic, Minneapolis 55455.
authors.forename: C A
authors.initials: CA
authors.lastname: Hanson
authors.forename: W
authors.initials: W
authors.lastname: Jaszcz
authors.forename: J H
authors.initials: JH
authors.lastname: Kersey
authors.forename: M G
authors.initials: MG
authors.lastname: Astorga
authors.forename: B A
authors.initials: BA
authors.lastname: Peterson
authors.forename: K J
authors.initials: KJ
authors.lastname: Gajl-Peczalska
authors.forename: G
authors.initials: G
authors.lastname: Frizzera
mesh_terms: D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm / Q000032:analysis; D015139:Blotting, Southern; D005260:Female; D015321:Gene Rearrangement; D006801:Humans; D007124:Immunoenzyme Techniques; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm