title: Hypocellular acute promyelocytic leukemia with a tetraploid clone characterized by two t(15;17).
abstract: We describe a case of hypocellular acute promyelocytic leukemia with a tetraploid clone characterized by two t(15;17). The large leukemia cells had a bizarre nuclear configuration and multiple Auer rods. A bone marrow biopsy specimen revealed a markedly hypocellular marrow (<10% cellularity) in the absence of myelofibrosis. Myelodysplastic features were not detected. Chromosome analysis of marrow cells revealed a karyotype of 92,XXYY,del(2)(q?),t(15;17)(q22;q21)x2. Interphase fluorescence in situ hybridization revealed that the marrow cells were composed of a tetraploid clone carrying double t(15;17) and normal diploid cells. The leukemia responded well to all-trans retinoic acid. We think that the tetraploidy could be caused by endoreduplication or endomitosis of the diploid clone with single t(15;17). The unique karyotype largely contributed to the cell morphology and marrow hypoplasia, while it may not have affected on the prognosis of the acute promyelocytic leukemia.
authors.affiliation: The First Department of Internal Medicine, Ehime University School of Medicine, Shingenobu, Ehime 791-0295, Japan. kkoji@m.ehime-u.ac.jp
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kojima
authors.forename: Michiyoshi
authors.initials: M
authors.lastname: Imaoka
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Noguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Narumi
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Uchida
authors.forename: Ikuya
authors.initials: I
authors.lastname: Sakai
authors.forename: Masaki
authors.initials: M
authors.lastname: Yasukawa
authors.forename: Shigeru
authors.initials: S
authors.lastname: Fujita
mesh_terms: D001854:Bone Marrow Cells / Q000166:cytology; D002884:Chromosomes, Human, Pair 15; D002886:Chromosomes, Human, Pair 17; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011123:Polyploidy; D017384:Sequence Deletion; D014178:Translocation, Genetic