title: Anaplastic large-cell lymphomas of B-cell phenotype are anaplastic lymphoma kinase (ALK) negative and belong to the spectrum of diffuse large B-cell lymphomas.
abstract: There is controversy in the literature as to whether anaplastic large-cell lymphoma of B-cell phenotype is related to the t(2;5)-positive T- or 'null' cell lymphoma of the same morphology. We report a study of 24 lymphomas with morphological features of anaplastic large-cell lymphoma which expressed one or more B-cell markers and lacked T-lineage markers. Clinical features were more in keeping with large B-cell lymphoma than with classical t(2;5)-positive anaplastic large-cell lymphoma, and immunostaining for anaplastic lymphoma kinase (ALK) protein provided no evidence for the (2;5) translocation (or one of its variants). The staining patterns for CD20 and CD79 were typical of diffuse large B-cell lymphoma, CD30 expression was variable, and most cases (15/22) lacked epithelial membrane antigen (EMA). These findings support the view that 'B-cell anaplastic large-cell lymphoma' is unrelated to t(2;5)-positive (ALK-positive) lymphoma, and that it represents a morphological pattern occasionally encountered among diffuse large B-cell lymphomas. By the same reasoning, most tumours diagnosed as 'ALK-negative anaplastic large-cell lymphoma of T-cell or null phenotype' probably belong to the spectrum of peripheral T-cell lymphomas.
authors.affiliation: Leukaemia Research Fund Immunodiagnostics Unit, Nuffield Department of Clinical Laboratory Sciences, John Radcliffe Hospital, Oxford, UK.
authors.forename: E
authors.initials: E
authors.lastname: Haralambieva
authors.forename: K A
authors.initials: KA
authors.lastname: Pulford
authors.forename: L
authors.initials: L
authors.lastname: Lamant
authors.forename: S
authors.initials: S
authors.lastname: Pileri
authors.forename: G
authors.initials: G
authors.lastname: Roncador
authors.forename: K C
authors.initials: KC
authors.lastname: Gatter
authors.forename: G
authors.initials: G
authors.lastname: Delsol
authors.forename: D Y
authors.initials: DY
authors.lastname: Mason
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077548:Anaplastic Lymphoma Kinase; D015703:Antigens, CD / Q000032:analysis; D018951:Antigens, CD20 / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D051925:CD79 Antigens; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D017730:Ki-1 Antigen / Q000032:analysis; D016393:Lymphoma, B-Cell / Q000145:classification* / Q000201:enzymology / Q000276:immunology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000201:enzymology / Q000276:immunology; D016399:Lymphoma, T-Cell / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011505:Protein-Tyrosine Kinases / Q000032:analysis; D020794:Receptor Protein-Tyrosine Kinases; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D015703:Antigens, CD; D018951:Antigens, CD20; D015415:Biomarkers; D051925:CD79 Antigens; C497883:CD79B protein, human; D017730:Ki-1 Antigen; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases