<abstract xmlns="http://www.w3.org/1999/xhtml"><p> The coexistence of t(9;22) and inv(16) has been described in a very limited number of cases of CML, de novo or therapy-related AML. We report a patient with CML who presented both inversion of chromosome 16 and Philadelphia chromosome and evolved towards the blast phase under treatment with Imatinib. Laboratory diagnosis and monitoring was made by flow cytometry, conventional cytogenetics and molecular genetics techniques. The inv(16), detected by karyotyping in the Philadelphia chromosome positive clone at the moment of the blast transformation, was retrospectively assessed by means of real-time PCR, and was proved to have been present since diagnosis. The bone marrow biopsy performed in the blast phase of CML confirmed the presence of blasts belonging to the myeloid lineage, with indications of monocytic differentiation, frequently associated with inv(16). Moreover, the case also associated a F359V tyrosine kinase domain mutation, resulting in intermediate resistance to Imatinib and Nilotinib, which imposed therapy-switch to Dasatinib. In our case the evolution was progressive, followed by death due to lack of response to tyrosine kinase inhibitors, 18 months after diagnosis. The coexistence of t(9;22) and inv(16) in CML seems to be associated with an aggressive clinical evolution and resistance to tyrosine kinase inhibitor therapy. Due to the very small number of cases described in literature, therapeutic decisions are still difficult for patients displaying these abnormalities</p></abstract>

The coexistence of t(9;22) and inv(16) has been described in a very limited number of cases of CML, de novo or therapy-related AML. We report a patient with CML who presented both inversion of chromosome 16 and Philadelphia chromosome and evolved towards the blast phase under treatment with Imatinib. Laboratory diagnosis and monitoring was made by flow cytometry, conventional cytogenetics and molecular genetics techniques. The inv(16), detected by karyotyping in the Philadelphia chromosome positive clone at the moment of the blast transformation, was retrospectively assessed by means of real-time PCR, and was proved to have been present since diagnosis. The bone marrow biopsy performed in the blast phase of CML confirmed the presence of blasts belonging to the myeloid lineage, with indications of monocytic differentiation, frequently associated with inv(16). Moreover, the case also associated a F359V tyrosine kinase domain mutation, resulting in intermediate resistance to Imatinib and Nilotinib, which imposed therapy-switch to Dasatinib. In our case the evolution was progressive, followed by death due to lack of response to tyrosine kinase inhibitors, 18 months after diagnosis. The coexistence of t(9;22) and inv(16) in CML seems to be associated with an aggressive clinical evolution and resistance to tyrosine kinase inhibitor therapy. Due to the very small number of cases described in literature, therapeutic decisions are still difficult for patients displaying these abnormalities

Co-expression of the CBFβ-MYH11 and BCR-ABL fusion genes in chronic myeloid leukaemia / Coexistenţa genelor de fuziune CBFβ-MYH11 şi BCR-ABL în leucemia mieloidă cronică

University of Medicine and Pharmacy, Iasi

University of Medicine and Pharmacy, Iasi; 2. Regional Institute of Oncology, Iasi

Revista Romana de Medicina de Laborator

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The coexistence of t(9;22) and inv(16) has been described in a very limited number of cases of CML, de novo or therapy-related AML. We report a patient with...

Co-expression of the CBFβ-MYH11 and BCR-ABL fusion genes in chronic myeloid leukaemia / Coexistenţa genelor de fuziune CBFβ-MYH11 şi BCR-ABL în leucemia mieloidă cronică

Pubblicato online: 23 giu 2015

Pagine: 221 - 230

Ricevuto: 12 nov 2014

Accettato: 13 apr 2015

DOI: https://doi.org/10.1515/rrlm-2015-0013

Parole chiave
chronic myeloid leukaemia, Philadelphia chromosome, inv(16), tyrosine kinase domain mutation

© by Angela Dăscălescu

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Co-expression of the CBFβ-MYH11 and BCR-ABL fusion genes in chronic myeloid leukaemia / Coexistenţa genelor de fuziune CBFβ-MYH11 şi BCR-ABL în leucemia mieloidă cronică

Pubblicato online: 23 giu 2015

Pagine: 221 - 230

Ricevuto: 12 nov 2014

Accettato: 13 apr 2015

DOI: https://doi.org/10.1515/rrlm-2015-0013

Parole chiavechronic myeloid leukaemia, Philadelphia chromosome, inv(16), tyrosine kinase domain mutation

© by Angela Dăscălescu

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Parole chiave
chronic myeloid leukaemia, Philadelphia chromosome, inv(16), tyrosine kinase domain mutation