title: Masked MLL gene rearrangement was disclosed in the clinical course and sequential development of chromosome abnormality in a patient with therapy related acute myelogenous leukemia.
abstract: Therapy related acute myelogenous leukemia in a 55-year-old Japanese woman is described. She had been treated for a diagnosis of non-Hodgkin's lymphoma 2 years before the onset of the secondary leukemia. She was diagnosed as AML (FAB: M2) with monosomy 7, and successfully treated by an intensive combination chemotherapy followed by an autologous peripheral blood stem cell transplantation. The disease relapsed shortly after the treatment, and the karyotype analysis revealed a complex abnormality accompanied with t(9;11)(p22;q23), however, monosomy 7 was absent. Southern blotting analysis was performed, and MLL rearrangement was evident in both the bone marrow samples obtained at that time and the cryopreserved marrow cells obtained at the onset of the disease. The bone marrow sample stored in a Carnoy solution at the onset was further analyzed, and three karyotype panels showing 45,XX, -7, t(9;11)(p22;q23) were found. Like this situation, a masked MLL rearrangement may have existed in some cases with hematopoietic malignancies, and appear to be disclosed in the clinical course.
authors.affiliation: First Department of Internal Medicine, Faculty of Medicine, Niigata University Medical Hospital, Niigata, Japan. hshigeo@med.niigata-u.ac.jp
authors.forename: Shigeo
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Ken
authors.initials: K
authors.lastname: Toba
authors.forename: Noriko
authors.initials: N
authors.lastname: Izumi
authors.forename: Naoko
authors.initials: N
authors.lastname: Sato
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Takahashi
authors.forename: Takuya
authors.initials: T
authors.lastname: Ozawa
authors.forename: Masato
authors.initials: M
authors.lastname: Moriyama
authors.forename: Sadao
authors.initials: S
authors.lastname: Aoki
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Furukawa
authors.forename: Miwako
authors.initials: M
authors.lastname: Narita
authors.forename: Masuhiro
authors.initials: M
authors.lastname: Takahashi
authors.forename: Yoshifusa
authors.initials: Y
authors.lastname: Aizawa
mesh_terms: D002471:Cell Transformation, Neoplastic / Q000235:genetics; D002869:Chromosome Aberrations; D002880:Chromosomes, Human, Pair 11; D002897:Chromosomes, Human, Pair 7; D002899:Chromosomes, Human, Pair 9; D020732:Cytogenetic Analysis; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D015321:Gene Rearrangement; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D016130:Immunophenotyping; D007945:Leukemia, Lymphoid / Q000235:genetics; D007951:Leukemia, Myeloid / Q000235:genetics; D015470:Leukemia, Myeloid, Acute / Q000209:etiology / Q000235:genetics*; D008228:Lymphoma, Non-Hodgkin / Q000473:pathology / Q000628:therapy; D008875:Middle Aged; D009006:Monosomy; D051788:Myeloid-Lymphoid Leukemia Protein; D016609:Neoplasms, Second Primary / Q000209:etiology / Q000235:genetics*; D011519:Proto-Oncogenes; D014157:Transcription Factors; D014178:Translocation, Genetic
chemical_list: D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase