title: A child with Philadelphia positive (Ph+)-acute leukemia with myeloid morphology: one case of stem cell origin.
abstract: Philadelphia positive (Ph+) acute myeloid leukemia (AML) is a rare and heterogeneous condition, mainly reported in adults, associated to poor prognosis and unfavorable response to therapy. Here we report clinical and laboratory findings in an 8-year-old patient diagnosed with Ph+ acute leukemia with myeloid (FAB M4) morphology. The patient consistently expressed variable levels of m-bcr, e1a2 transcripts during a 42-month follow-up after two different stem cell transplantation protocols. An immunophenotypic switch was documented, from a mixed, myeloid-lymphoid lineage to a full lymphoid phenotype following stem cell transplants, in association with an immature B-cell gene rearrangement profile and clonal instability during clinical progression. This report indicates a stem cell origin as previously suggested for Ph+ AML.
authors.affiliation: Bone Marrow Transplantation Centre (CEMO), Rio de Janeiro, Brazil. biomol@inca.gov.br
authors.forename: Rocío
authors.initials: R
authors.lastname: Hassan
authors.forename: Ivone
authors.initials: I
authors.lastname: Otazú
authors.forename: Maria Helena
authors.initials: MH
authors.lastname: Ornellas
authors.forename: Virginia
authors.initials: V
authors.lastname: Pires
authors.forename: Maria Kadma
authors.initials: MK
authors.lastname: Carriço
authors.forename: Héctor
authors.initials: H
authors.lastname: Seuánez
authors.forename: Daniel
authors.initials: D
authors.lastname: Tabak
authors.forename: Ilana
authors.initials: I
authors.lastname: Zalcberg
mesh_terms: D019070:Cell Lineage; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016130:Immunophenotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000473:pathology*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000378:metabolism* / Q000473:pathology*
chemical_list: D012333:RNA, Messenger