title: [Reappearance of t(12;17)-positive primary myelofibrosis following Ph+ CML cell reduction by imatinib].
abstract: A 67-years old woman was referred to our hospital in October 1992 with thrombocytopenia and splenomegaly. A bone marrow biopsy revealed decreased cellularity, with moderately increased reticulin fibrosis and discrete dysmorphic megakaryocytes but no signs of dysplasia in the erythroid or the myeloid lineages. The karyotype of the bone marrow cells was t(12;17) (q24;q11). She was diagnosed as having agnogenic myeloid metaplasia. The patient received only blood transfusions until November 1998 when leukocytosis with immature cells started to appear. The bone marrow aspiration analysis showed increased cellularity and chromosomal analysis demonstrated the presence of t(9;22) (q34;q11) without any t(12;17) (q24;q11) abnormality. Because IFN therapy and oral administration of hydroxyurea did not show any cytological effect, administration of imatinib mesylate was started from December 2001. The Ph-positive cells as demonstrated by the FISH method had decreased to 7% by April 2003. But the t(12;17)(q24;q11) positive clones, which were observed on the first admission, again appeared in the peripheral blood, whereas Ph clones were detected in only one out of 24 cells examined. During the course of treatment with imatinib mesylate for chronic myelogenous leukemia which developed from agnogenic myeloid metaplasia accompanied with t(12;17)(q24;q11) translocation, the co-existence of two clones derived from, possibly, stem cells was identified.
authors.affiliation: Fourth Department of Internal Medicine, Sapporo Medical University School of Medicine.
authors.forename: Naoko
authors.initials: N
authors.lastname: Araki
authors.forename: Rishu
authors.initials: R
authors.lastname: Takimoto
authors.forename: Akihito
authors.initials: A
authors.lastname: Fujimi
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Murase
authors.forename: Hironobu
authors.initials: H
authors.lastname: Araki
authors.forename: Naoki
authors.initials: N
authors.lastname: Takahira
authors.forename: Takuya
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Takeshi
authors.initials: T
authors.lastname: Terui
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Kogawa
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hirayama
authors.forename: Junji
authors.initials: J
authors.lastname: Kato
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Niitsu
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001549:Benzamides; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D007621:Karyotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000175:diagnosis / Q000188:drug therapy*; D010879:Piperazines / Q000009:adverse effects* / Q000627:therapeutic use; D055728:Primary Myelofibrosis / Q000209:etiology* / Q000235:genetics; D011743:Pyrimidines / Q000009:adverse effects* / Q000627:therapeutic use; D012008:Recurrence; D014178:Translocation, Genetic
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate