title: Hybrid leukemia and the 5q-abnormality.
abstract: Most cases of acute leukemia with deletions of chromosome 5q (5q-) are acute myelogenous leukemia. 5q- in acute lymphoid leukemia is rare. We studied a case of acute leukemia with 5q- using morphologic, cytochemical, immune and molecular techniques. Morphologic and cytochemical techniques were consistent with ALL (FAB L-2, PAS+, MPO-, ASD-). TdT was present. Immune studies suggested a T-cell phenotype (CD5+, CD7+); however, there was no rearrangement of the T beta-cell receptor gene. Surprisingly, the leukemia cells also expressed the CD13 myeloid antigen. Dual staining analysis showed co-expression of lymphoid and myeloid antigens on most cells. Based on these data and a review of previous reports we suggest that acute leukemia associated with the 5q- abnormality can occur in an immature stem cell resulting in a hybrid leukemia.
authors.affiliation: Department of Medicine, UCLA School of Medicine 90024-1678.
authors.forename: G
authors.initials: G
authors.lastname: Sun
authors.forename: S
authors.initials: S
authors.lastname: Wormsley
authors.forename: R S
authors.initials: RS
authors.lastname: Sparkes
authors.forename: F
authors.initials: F
authors.lastname: Naeim
authors.forename: R P
authors.initials: RP
authors.lastname: Gale
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D001853:Bone Marrow / Q000473:pathology; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D025063:Chromosome Disorders; D002895:Chromosomes, Human, Pair 5; D005260:Female; D006801:Humans; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D015703:Antigens, CD; D011948:Receptors, Antigen, T-Cell