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Soriani S, Guido V, Bertani G, Cesana C, Motta V, De Canal G, De Paoli E, Veronese S, Bonoldi E, Romitti L. BCR/ABL1 fluorescence in situ hybridization fusion signals on both copies of chromosome 22 in a Philadelphia-masked chronic myeloid leukemia case: implication for the therapy. Hematol Rep 2021; 13:8795. [PMID: 33824712 PMCID: PMC8018256 DOI: 10.4081/hr.2021.8795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 02/01/2021] [Indexed: 11/22/2022] Open
Abstract
The cytogenetic hallmark of Chronic Myeloid Leukemia (CML) is the presence of Philadelphia (Ph) chromosome, which results from a reciprocal translocation t(9;22)(q34;q11). In this report, we describe a CML patient with no evidence of Ph chromosome but trisomy of chromosome 8 as single cytogenetic abnormality and a typical e14a2 (b3a2) BCR-ABL1 fusion transcript. Fluorescence In Situ Hybridization (FISH) analysis revealed an uncommon signal pattern: the fusion signals were located on both copies of chromosome 22. During the course of the disease the appearance of the p.(Tyr315Ile) mutation was recorded. To the best of our knowledge this is the first Ph chromosome-negative CML case with e14a2 (b3a2) BCR-ABL1 transcript and p.(Tyr315Ile) mutation.
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Soliman DS, Amer AM, Mudawi D, Al-Sabbagh Z, Alkuwari E, Al-Sabbagh A, Ibrahim F, Yassin MA. Chronic Myeloid Leukemia with cryptic Philadelphia translocation and extramedullary B-lymphoid blast phase as an initial presentation. ACTA BIO-MEDICA : ATENEI PARMENSIS 2018; 89:38-44. [PMID: 29633732 PMCID: PMC6179102 DOI: 10.23750/abm.v89i3-s.7219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Indexed: 11/25/2022]
Abstract
Chronic Myeloid Leukemia (CML) is a clonal myeloproliferative neoplasm (MPN) characterized by the presence of a reciprocal translocation between the long arms of chromosomes 9 and 22, t(9;22)(q34:q11), resulting in fusion of the break point cluster region (BCR) with the ABL gene, which forms an oncogene, the transcript of which is an oncoprotein with a tyrosine kinase function. In the great majority of CML; BCR/ABL1 is cytogenetically visualized as t(9;22); giving rise to the Ph chromosome, harboring the chimeric gene. Cryptic or masked translocations occur in 2-10% patients with no evidence for the BCR/ABL rearrangement by conventional cytogenetics but are positive by Fluorescence in Situ Hybridization (FISH) and/or reverse transcriptase polymerase chain reaction (RT-PCR). These patients are described as Philadelphia negative (Ph negative) BCR/ABL1-positive CML with the chimeric gene present on the derivative chromosome 22, as in most CML cases, or alternatively on the derivative 9 in rare occasions. In the majority of cases, CML is diagnosed in the chronic phase; it is less frequently diagnosed in accelerated crises, and occasionally, its initial presentation is as acute leukemia. The prevalence of extramedullary blast phase (BP) has been reported to be 7-17% in patients with BP. Surprisingly, no extramedullary blast crises of B-lymphoid lineage have been reported before among cases of CML as the initial presentation. We report an adult male diagnosed as CML-chronic phase when he was shortly presented with treatment-naive extramedullary B-lymphoid blast crises involving multiple lymph nodes, with no features of acceleration or blast crises in the peripheral blood (PB) and bone marrow (BM). In addition the patient had variant/cryptic Philadelphia translocation. This is the first report of CML, on the best of our knowledge, with extramedullary B-lymphoid blast phase, as initial presentation, that showed a cryptic Ph translocation. (www.actabiomedica.it)
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Affiliation(s)
- Dina S Soliman
- Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha,Qatar.
| | - Aliaa M Amer
- Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha,Qatar.
| | - Deena Mudawi
- Department of Hematology and Medical Oncology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
| | - Zafar Al-Sabbagh
- Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha,Qatar.
| | - Einas Alkuwari
- Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha,Qatar.
| | - Ahmad Al-Sabbagh
- Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha,Qatar.
| | - Feryal Ibrahim
- Department of Laboratory Medicine and Pathology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha,Qatar.
| | - Mohamed A Yassin
- Department of Hematology and Medical Oncology, National Center for Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
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Cryptic BCR-ABL fusion gene as variant rearrangement in chronic myeloid leukemia: molecular cytogenetic characterization and influence on TKIs therapy. Oncotarget 2018; 8:29906-29913. [PMID: 28404889 PMCID: PMC5444712 DOI: 10.18632/oncotarget.15369] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 01/16/2017] [Indexed: 11/29/2022] Open
Abstract
At diagnosis, about 5% of Chronic Myeloid Leukemia (CML) patients lacks Philadelphia chromosome (Ph), despite the presence of the BCR/ABL rearrangement. Two mechanisms have been proposed about the occurrence of this rearrangement: the first one is a cryptic insertion between chromosomes 9 and 22; the second one involves two sequential translocations: a classic t(9;22) followed by a reverse translocation, which reconstitutes the normal morphology of the partner chromosomes. Out of 398 newly diagnosed CML patients, we selected 12 Ph-negative cases. Six Ph-negative patients treated with tyrosine kinase inhibitors (TKIs) were characterized, in order to study the mechanisms leading to the rearrangement and the eventual correlation with prognosis in treatment with TKIs. FISH analysis revealed cryptic insertion in 5 patients and classic translocation in the last one. In more detail, we observed 4 different patterns of rearrangement, suggesting high genetic heterogeneity of these patients. In our cases, the BCR/ABL rearrangement mapped more frequently on 9q34 region than on 22q11 region, in contrast to previous reports. Four patients, with low Sokal risk, achieved Complete Cytogenetic Response and/or Major Molecular Response after TKIs therapy. Therapy resistance was observed in one patient with duplication of BCR/ABL rearrangement and in another one with high risk. Even if the number patient is inevitably low, we can confirm that the rare Ph-negative CML patients do not constitute a “warning” category, meanwhile the presence of further cytogenetic abnormalities remains an adverse prognostic factor even in TKI era.
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Shao L, Miller S, Keller-Ramey J, Zhang Y, Roulston D. Cytogenetic, fluorescence in situ hybridization, and genomic array characterization of chronic myeloid leukemia with cryptic BCR-ABL1 fusions. Cancer Genet 2015; 208:396-403. [DOI: 10.1016/j.cancergen.2015.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 04/03/2015] [Accepted: 04/06/2015] [Indexed: 10/23/2022]
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Cetin Z, Yakut S, Karadogan I, Kupesiz A, Timuragaoglu A, Salim O, Tezcan G, Alanoglu G, Ozbalci D, Hazar V, Yesilipek MA, Undar L, Luleci G, Berker S. Aberrations of chromosomes 9 and 22 in acute lymphoblastic leukemia cases detected by ES-fluorescence in situ hybridization. Genet Test Mol Biomarkers 2012; 16:318-23. [PMID: 22360868 DOI: 10.1089/gtmb.2011.0186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A reciprocal translocation between chromosomes 9 and 22 creates oncogenic BCR/ABL fusion in the breakpoint region of the derivative chromosome 22. The aim of this study was to evaluate the importance of atypical fluorescence in situ hybridization (FISH) signal patterns in pediatric and adult acute lymphoblastic leukemia (ALL) cases. We evaluated t(9;22) translocation in 208 cases with ALL (294 tests), including 139 childhood and 69 adult cases by FISH technique using BCR/ABL extra signal (ES) probe. FISH signal patterns observed in pediatric ALL cases were as follows; Major-BCR/ABL (M-BCR/ABL) (1.4%), minor-BCR/ABL (m-BCR/ABL) (3.6%), trisomy 9 (4.3%), trisomy 22 (4.3%), trisomy or tetrasomy of both chromosomes 9 and 22 (2.9%), monosomy 9 (1.4%), monosomy 22 (0.7%), ABL gene amplification (1.4%), derivative chromosome 9 deletion (1.4%), and extra copies of the Philadelphia chromosome (1.4%). FISH signal patterns observed in adult ALL cases were as follows; M-BCR/ABL (5.8%), m-BCR/ABL (11.6%), two different cell clones with major and minor BCR/ABL signal pattern (2.9%), extra copies of Philadelphia chromosome (4.3%), derivative chromosome 9 deletion (1.4%), trisomy 9 (2.9%), tetraploidy (1.4%), monosomy 9 (1.4%), trisomy 22 (1.4%), and coexistence of both trisomy 22 and monosomy 9 (1.4%). Trisomy 9, trisomy 22, and polyploidy of chromosomes 9 and 22 were specific atypical FISH signal patterns for childhood B cell acute lymphoblastic leukemia (B-ALL) patients. However, monosomy 9 and ABL gene amplification were highly specific for childhood T cell acute lymphoblastic leukemia (T-ALL) patients. Our report presents the correlation between atypical FISH signal patterns and clinical findings of a large group of ALL cases.
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Affiliation(s)
- Zafer Cetin
- Department of Medical Biology, Akdeniz University, Antalya, Turkey
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Shibata Y, Malhotra A, Dutta A. Detection of DNA fusion junctions for BCR-ABL translocations by Anchored ChromPET. Genome Med 2010; 2:70. [PMID: 20860819 PMCID: PMC3092121 DOI: 10.1186/gm191] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 06/09/2010] [Accepted: 09/22/2010] [Indexed: 12/13/2022] Open
Abstract
Anchored ChromPET, a technique to capture and interrogate targeted sequences in the genome, has been developed to identify chromosomal aberrations and define breakpoints. Using this method, we could define the BCR-ABL1 translocation DNA breakpoint to a base-pair resolution in Philadelphia chromosome-positive samples. This DNA-based method is highly sensitive and can detect the fusion junction using samples from which it is hard to obtain RNA or cells where the RNA expression has been silenced.
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Affiliation(s)
- Yoshiyuki Shibata
- Department of Biochemistry and Molecular Genetics, University of Virginia, School of Medicine, 1300 Jefferson Pk Ave, Charlottesville, VA 22908-0733, USA.
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Matsushita H, Masukawa A, Arakawa S, Ogawa Y, Asai S, Yabe M, Ando K, Miyachi H. Persistence of derivative chromosome 22 after achieving a major molecular response in chronic myeloid leukemia with a cryptic BCR-ABL1 fusion gene. Int J Hematol 2009; 90:623-626. [PMID: 19998064 DOI: 10.1007/s12185-009-0448-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 10/27/2009] [Accepted: 11/05/2009] [Indexed: 11/27/2022]
Abstract
We herein report the findings of a 47-year-old Japanese female with chronic myeloid leukemia (CML) with a cryptic BCR-ABL1 transcript on chromosome 9 and a derivative chromosome 22 unrelated to BCR-ABL1. Although she achieved and continued to demonstrate a major molecular response to imatinib treatment following interferon-alpha, there was persistence of a derivative chromosome 22. A detailed chromosome/molecular studies, including serial karyotyping analysis, finally resulted in the karyotyping at the disease onset to be 47,XX,+del(22)(q11.2), with two genetic evens, namely a cryptic BCR-ABL1 transcript on chromosome 9 and derivative chromosome 22 unrelated to BCR-ABL1. This CML case with these two rare genetic events thus raises diagnostic issues such as the difficulty in making a concise evaluation of the chromosomal/molecular events and an accurate disease prognosis, as well as the difficulty in determining the disease remission status after treatment.
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Affiliation(s)
- Hiromichi Matsushita
- Department of Laboratory Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan.
| | - Atsuko Masukawa
- Clinical Laboratory, Tokai University Hospital, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Satoshi Arakawa
- Clinical Laboratory, Tokai University Hospital, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Yoshiaki Ogawa
- Department of Hematology/Oncology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Satomi Asai
- Department of Laboratory Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Miharu Yabe
- Department of Laboratory Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Kiyoshi Ando
- Department of Hematology/Oncology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Hayato Miyachi
- Department of Laboratory Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
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Virgili A, Brazma D, Reid AG, Howard-Reeves J, Valgañón M, Chanalaris A, De Melo VA, Marin D, Apperley JF, Grace C, Nacheva EP. FISH mapping of Philadelphia negative BCR/ABL1 positive CML. Mol Cytogenet 2008; 1:14. [PMID: 18638369 PMCID: PMC2500019 DOI: 10.1186/1755-8166-1-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Accepted: 07/18/2008] [Indexed: 12/12/2022] Open
Abstract
Background Chronic myeloid leukaemia (CML) is a haematopoietic stem cell disorder, almost always characterized by the presence of the Philadelphia chromosome (Ph), usually due to t(9;22)(q34;q11) or its variants. The Ph results in the formation of the BCR/ABL1 fusion gene, which is a constitutively activated tyrosine kinase. Around 1% of CML patients appear to have a Ph negative karyotype but carry a cryptic BCR/ABL1 fusion that can be located by fluorescence in situ hybridisation (FISH) at chromosome 22q11, 9q34 or a third chromosome. Here we present FISH mapping data of BCR and ABL1 flanking regions and associated chromosomal rearrangements in 9 Ph negative BCR/ABL1 positive CML patients plus the cell line CML-T1. Results BCR/ABL1 was located at 9q34 in 3 patients, 22q11 in 5 patients and CML-T1 and 22p11 in 1 patient. In 3 of 6 cases with the fusion at 22q11 a distal breakpoint cluster was found within a 280 Kb region containing the RAPGEF1 gene, while in another patient and the CML-T1 the distal breakpoint fell within a single BAC clone containing the 3' RXRA gene. Two cases had a duplication of the masked Ph while genomic deletions of the flanking regions were identified in 3 cases. Even more complex rearrangements were found in 3 further cases. Conclusion BCR/ABL1 formation resulted from a direct insertion (one step mechanism) in 6 patients and CML-T1, while in 3 patients the fusion gene originated from a sequence of rearrangements (multiple steps). The presence of different rearrangements of both 9q34 and 22q11 regions highlights the genetic heterogeneity of this subgroup of CML. Future studies should be performed to confirm the presence of true breakpoint hot spots and assess their implications in Ph negative BCR/ABL1 positive CML.
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Affiliation(s)
- Anna Virgili
- Molecular Cytogenetics, Academic Haematology, Royal Free and UCL Medical School, Rowland Hill Street, London, NW3 2PF, UK.
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Mark HFL, Sokolic RA, Mark Y. Conventional cytogenetics and FISH in the detection of BCR/ABL fusion in chronic myeloid leukemia (CML). Exp Mol Pathol 2006; 81:1-7. [PMID: 16729999 DOI: 10.1016/j.yexmp.2006.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Accepted: 03/13/2006] [Indexed: 11/29/2022]
MESH Headings
- Chromosomes, Human, Pair 9/genetics
- Cytogenetic Analysis/methods
- DNA, Neoplasm/analysis
- Fusion Proteins, bcr-abl/genetics
- Humans
- In Situ Hybridization, Fluorescence/methods
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Translocation, Genetic
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Affiliation(s)
- Hon Fong L Mark
- Cytogenetics Laboratories, Boston University School of Medicine, 700 Albany Street, Boston, MA 02118, USA.
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Phan TX, Hoang AV, Huynh VM, Nguyen KT, Nguyen TB, Huynh N, Pham QT, Tran VB, Tran VB, Tokunaga K, Sato Y. Unique secondary chromosomal abnormalities are frequently found in the chronic phase of chronic myeloid leukemia in southern Vietnam. ACTA ACUST UNITED AC 2006; 168:59-68. [PMID: 16772122 DOI: 10.1016/j.cancergencyto.2005.12.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Revised: 12/06/2005] [Accepted: 12/14/2005] [Indexed: 01/03/2023]
Abstract
During the Vietnam War, southern Vietnam was exposed to a large amount of dioxin, a strong human carcinogen. Although we have observed much shorter survival in southern Vietnamese chronic myeloid leukemia (CML) patients, the cause remains to be clarified. Here, we report cytogenetic and molecular findings for 47 CML patients. Cytogenetically, the Philadelphia (Ph) chromosome was found in 44 patients (93.6%); of the remaining 3 patients with Ph-negative CML, 2 exhibited BCR/ABL transcripts but no BCR/ABL FISH fusion signals, suggesting the existence of two clones, with and without the BCR/ABL fusion gene. Surprisingly, in 17 patients (36.2%) (4 at diagnosis, 11 during chronic phase, and 2 in accelerated phase), we found several unique secondary chromosome abnormalities including trisomy 13, partial trisomy 13, and abnormalities of 1p, 3p, 6p, 7p, 10p, and 11p, which are different from the so-called additional chromosome abnormalities (extra Ph, +8, i(17q), +19, and +21) observed in blastic phase CML. FISH analysis revealed the Ph translocation with der(9) deletion in 11 patients (23.4%). Of these, 2 had two clones, with and without der(9) deletion, suggesting that der(9) deletion would occur in a subset of patients during disease progression. These observations point to preexisting genetic instability that induces various secondary chromosome abnormalities and multiple clones, resulting in shorter survival.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Chromosome Aberrations
- Chromosomes, Human, Pair 13/genetics
- Female
- Fusion Proteins, bcr-abl/genetics
- Gene Deletion
- Humans
- In Situ Hybridization, Fluorescence
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative/genetics
- Male
- Middle Aged
- Philadelphia Chromosome
- RNA, Messenger/analysis
- Translocation, Genetic/genetics
- Trisomy/genetics
- Vietnam
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Affiliation(s)
- Thi Xinh Phan
- Division of Ultrafine Structure, Department of Pathology, Research Institute of International Medical Center of Japan, Toyama 1-21-1, Shinjuku-ku, Tokyo, 162-0052, Tokyo, Japan
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Batista DAS, Hawkins A, Murphy KM, Griffin CA. BCR/ABL rearrangement in two cases of Philadelphia chromosome negative chronic myeloid leukemia: deletion on the derivative chromosome 9 may or not be present. ACTA ACUST UNITED AC 2006; 163:164-7. [PMID: 16337861 DOI: 10.1016/j.cancergencyto.2005.04.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Accepted: 04/27/2005] [Indexed: 10/25/2022]
Abstract
The BCR/ABL gene rearrangement is the causing factor in chronic myeloid leukemia (CML). In most cases, it is cytogenetically visualized as a translocation between chromosomes 9 and 22, known as the Philadelphia (Ph) translocation. About 5-10% of CML patients lack cytogenetic evidence of the Ph translocation but show BCR/ABL fusion by fluorescence in situ hybridization (FISH) or reverse transcriptase-polymerase chain reaction. Deletions around the breakpoints on the derivative 9 including ABL and or BCR sequences occur in 10-15% of Ph+ CML patients and are thought to have prognostic significance. We describe two patients with CML and normal karyotype in whom cryptic rearrangements involving chromosomes 9 and 22 resulted in the causative BCR/ABL gene. FISH with a three-color probe combination revealed BCR/ABL fusion on chromosome 9 without deletion in one patient; the other patient had BCR/ABL on chromosome 22 with an associated derivative 9 deletion. We discuss the proposed mechanisms in the formation of BCR/ABL in the setting of a normal karyotype. Some authors reported that patients with the chimeric gene located on the derivative 9 have a poor clinical course. We suggest that deletion rather than location of the chimeric gene alone is more likely to be associated with prognosis.
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MESH Headings
- Adult
- Chromosomes, Human, Pair 22
- Chromosomes, Human, Pair 9
- Female
- Fusion Proteins, bcr-abl/genetics
- Gene Rearrangement
- Humans
- In Situ Hybridization, Fluorescence
- Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative/genetics
- Middle Aged
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Deletion
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Affiliation(s)
- Denise A S Batista
- Department of Pathology, Division of Molecular Pathology, Johns Hopkins University, 600 North Wolfe Street, Park SB 202, Baltimore, MD 21287, USA.
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