Frequency of the BCR/ABL rearrangements and associated alterations detected by FISH during monitoring of patients taking imatinib mesylate in isolation

A introdução do mesilato de imatinibe como tratamento da leucemia mielóide crônica tem salvado muitos pacientes, mas o sucesso da terapia tem sido prejudicado pela resistência e possível não destruição do clone maligno. Este artigo descreve a resposta citogenética e padrões citogenéticos anormais envolvendo os genes ABL e BCR detectados por FISH em pacientes em uso exclusivo de imatinibe. Os resultados mostraram que outras alterações envolvendo os genes BCR e ABL não parecem estar relacionadas à resistência à droga, elas ocorrem em baixas freqüências e podem não estar associadas à resposta citogenética ou ao tempo de tratamento. Contudo, a resposta ao imatinibe parece ser individual e imprevisível, independente do tempo e do início do tratamento após o diagnóstico.The introduction of imatinib mesylate as treatment of chronic myelogenous leukemia has saved many patients, but the success of therapy is hampered by resistance and possible non-destruction of the malignant clone. This article describes the cytogenetic responses and abnormal cytogenetic patterns involving the ABL and BCR genes detected by FISH in patients who use exclusively imatinib. The results showed that other alterations involving the BCR and ABL genes do not seem to be related to resistance to the drug as they occur in low frequencies and can not be associated to the cytogenetic response or to the time of treatment. Moreover, the response to imatinib seems to be individual and unpredictable, independent of the time of treatment and of its initiation after diagnosis

Translocation (11;19)(q23;p13.3) associated with a novel t(5;16) (ql3;q22) in a patient with acute myelocytic leukemia

A novel association of t(11;19)(q23;p13) and t(5;16)(q13;q22) was detected by G-banding and spectral karyotyping studies in an 18-year-old patient. While balanced t(11; 19) has been often described in acute myelocytic leukemia (AML) French-American-British Cooperative Group subtypes M4 and M5, this patient was diagnosed with the variant AML-M4 with eosinophilia (AML-M4Eo), which is associated with abnormalities in 16q22 and has good prognosis. However, the patient relapsed after allogeneic transplant and died within 2 years of diagnosis, which suggests that the association of these two translocations correlates with a poor prognosis. This report expands the molecular basis of the variability in clinical outcomes and adds the novel t(5;16)(q13;q22) to the spectrum of chromosome 16q22 abnormalities in AML. (C) 2003 Elsevier B.V. All rights reserved

Estudo cromossômico no sangue periférico de pacientes com diferentes tipos de leucemia do Hospital de Base, São José do Rio Preto - SP Chromosomal study of peripheral blood in patients with different types of leukemia from Hospital de Base, São José do Rio Preto - SP

A análise das alterações cromossômicas em leucemias tem uma aplicação direta no diagnóstico, prognóstico e tratamento dos pacientes. Além disso, permite o entendimento dos processos biológicos envolvidos na carcinogênese. Este trabalho apresenta os resultados do estudo cariotípico de 51 casos de diferentes tipos de leucemias. Os cromossomos foram obtidos através de cultura de células de sangue periférico, realizadas por 24 ou 48 horas, sem estimulação mitogênica. Em 74% dos pacientes foram observadas anomalias cromossômicas clonais como translocações, deleções, monossomias e trissomias. Muitas alterações foram compatíveis com outras previamente descritas e outras não, como a translocação envolvendo os cromossomos 9 e 22, que origina o cromossomo Philadelphia e uma translocação complexa envolvendo os cromossomos 4, 7 e 11. Os resultados reforçam a importância da análise cromossômica em leucemia e seus benefícios para o paciente.<br>The analysis of chromosomal changes in leukemia has had a direct involvement in the diagnosis, prognosis and treatment of patients. Furthermore, it has allowed the understanding of biological processes involved in carcinogenesis. This work presents the results of a kariotypic study of 51 cases of different types of leukemia. The chromosomes were obtained through a 24 or 48 hour culture of cells of the peripheral blood with no mitogenic stimulation. In 74,5% of patients clonal chromosomic abnormalities were observed such as translocations, deletions, monosomies and trisomies. Many of the alterations were similar to results previously published and others were not such as the translocation involving the chromosomes 9 and 22, which leads to the Philadelphia chromosome and the complex translocation involving the chromosomes 4, 7 and 11. The results emphasized the importance of chromosomal analysis in leukemia, its benefits to the patient and to the knowledge of the biological mechanisms involved in this pathology

Atypical chromosome abnormalities in acute myeloid leukemia type M4

This study reports an adult AML-M4 patient with atypical chromosomal aberrations present in all dividing bone marrow cell at diagnosis: t(1;8)(p32.1;q24.2), der(9)t(9;10)(q22;?), and ins(19;9)(p13.3;q22q34) that may have originated transcripts with leukemogenic potential.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES