title: Leukaemia-associated immunophenotypes (LAIP) are observed in 90% of adult and childhood acute lymphoblastic leukaemia: detection in remission marrow predicts outcome.
abstract: Analysis of differentiation antigens on leukaemic blasts is routinely done for diagnostic purposes, i.e. determination of stage of differentiation and lineage assignment. Acute lymphoblastic leukaemias are also frequently characterized by a leukaemia-associated immunophenotype (LAIP), either the coexpression of differentiation antigens physiologically restricted to other stages of differentiation (asynchronous LAIP) or cell lineages (aberrant LAIP). We defined LAIP in 241 consecutive unselected B-lineage (n = 193) and T-lineage (n = 48) ALL by three-colour flow cytometry using directly conjugated monoclonal antibodies. The incidence of LAIP was found to be 91.7%. In 63% of patients two to six leukaemia-associated expression patterns were detected. In order to study the specificity of LAIP in a therapy-relevant setting, remission bone marrow samples from patients with B-lineage ALL were analysed for the expression of T-lineage-associated phenotypes on the normal bone marrow cells and vice versa. The frequency of all T-lineage LAIP+ cells and all aberrant B-lineage LAIP+ cells was <1% in regenerating bone marrow samples at different timepoints. The incidence and clinical significance of LAIP+ cells was studied in 196 remission marrows of 70 ALL patients (55 remaining in CCR, 14 with bone marrow relapse, one with isolated CNS relapse). The presence of >1% LAIP+ at two consecutive timepoints predicted 5/8 bone marrow relapses in B-lineage ALL. The occurrence of LAIP+ cells >1% in T-lineage ALL after induction therapy predicted relapse in 7/7 cases. In conclusion, flow cytometric detection of LAIP+ cells appears to be a powerful tool for the prediction of outcome in ALL.
authors.affiliation: Department of Haematology and Oncology, University of Göttingen, Germany. fgriesi@med.uni-goettingen.de
authors.forename: F
authors.initials: F
authors.lastname: Griesinger
authors.forename: M
authors.initials: M
authors.lastname: Pirò-Noack
authors.forename: N
authors.initials: N
authors.lastname: Kaib
authors.forename: M
authors.initials: M
authors.lastname: Falk
authors.forename: A
authors.initials: A
authors.lastname: Renziehausen
authors.forename: C
authors.initials: C
authors.lastname: Troff
authors.forename: D
authors.initials: D
authors.lastname: Grove
authors.forename: S
authors.initials: S
authors.lastname: Schnittger
authors.forename: T
authors.initials: T
authors.lastname: Büchner
authors.forename: J
authors.initials: J
authors.lastname: Ritter
authors.forename: W
authors.initials: W
authors.lastname: Hiddemann
authors.forename: B
authors.initials: B
authors.lastname: Wörmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology; D019070:Cell Lineage; D002648:Child; D002675:Child, Preschool; D006801:Humans; D016130:Immunophenotyping; D008875:Middle Aged; D010641:Phenotype; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000276:immunology*; D011379:Prognosis; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D015703:Antigens, CD