title: Biologic heterogeneity in Philadelphia chromosome-positive acute leukemia with myeloid morphology: the Eastern Cooperative Oncology Group experience.
abstract: Evaluable karyotypes were available in 776 of 1148 adult patients who were entered on acute myeloid leukemia (AML) treatment protocols of the Eastern Cooperative Oncology Group. Among these, we found seven patients (0.9%) with t(9;22)(q34;q11), the Philadelphia (Ph) chromosome, in bone marrow metaphases. All fulfilled the FAB criteria for AML (three M0, two M1, two M2), although one patient presented with an additional, distinct lymphoid blast cell population. Chromosomal aberrations in addition to the Ph chromosome were seen in four patients (including two cases of monosomy 7). Molecular analysis by polymerase chain reaction in four patients tested revealed variable BCR/ABL transcript forms (ela2, b2a2, b3a2, b2a3+ela2). By immunophenotyping, all seven patients were myeloid based on the overall antigen expression pattern. However, all but one demonstrated lymphoid-associated antigens on the myeloid blast cells. The six evaluable patients failed to respond to treatment with a standard anthracycline/cytosine arabinoside-containing regimen. We conclude that the incidence of the Ph chromosome in AML is very low. Although both genotypically and phenotypically heterogenous, Ph chromosome-positive AML, represents a clinically distinct entity with poor outcome.
authors.affiliation: Department Oncology, Montefiore and Albert Einstein Cancer Center, Bronx, New York, USA.
authors.forename: E
authors.initials: E
authors.lastname: Paietta
authors.forename: J
authors.initials: J
authors.lastname: Racevskis
authors.forename: J M
authors.initials: JM
authors.lastname: Bennett
authors.forename: D
authors.initials: D
authors.lastname: Neuberg
authors.forename: P A
authors.initials: PA
authors.lastname: Cassileth
authors.forename: J M
authors.initials: JM
authors.lastname: Rowe
authors.forename: P H
authors.initials: PH
authors.lastname: Wiernik
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis; D002869:Chromosome Aberrations; D025063:Chromosome Disorders; D016001:Confidence Intervals; D005260:Female; D005819:Genetic Markers; D006801:Humans; D016130:Immunophenotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D005819:Genetic Markers