Contributions
Abstract: PB1962
Type: Publication Only
Background
Chronic myeloid leukemia (CML) is characterized by formation of Philadelphia (Ph) chromosome as a result of reciprocal translocation between chromosome 22 and 9 i.e. t(9;22)(q34;q11.2). Additional cytogenetic abnormalities ACAs are reported internationally in 5-12% newly diagnosed CML.
Aims
The study was done to observe the frequency of cytogenetic abnormalities in CML in addition to Ph chromosome at the time of diagnosis, their baseline hematological characteristics and correlate their outcome on follow up.
Methods
This was a cross sectional study carried out at the department of Cytogenetics and Molecular Pathology of National Institute of Blood Diseases and Bone Marrow Transplant Karachi Pakistan from May 2010 to September 2016.All the patients diagnosed with CML during the study period on the basis of morphological and cytogenetic analysis were included and observed for ACAs. Baseline cytogenetic analysis was performed on overnight, 24-hrs unstimulated and 72-hrs stimulated bone marrow cultures using standard procedures. The GTG (G-bands via trypsin using giemsa) banding technique was applied, karyotypes were described according to the International System for Human Cytogenetic Nomenclature (ISCN) 2013, karyogram were made using Metasystem ®. BCR-ABL1 by real-time quantitative PCR was done by QIAGEN kits on Rotor-Gene Q 5plex HRM instrument with 72-tubes rotor, at baseline and at 18 months of treatment performed on peripheral blood and bone marrow. MMR was defined as 03 log reduction from the baseline.
Results
Out of total 222 cases of CML,18(8.1%) patients revealed ACAs; we found –Y, double Ph chromosome and trisomy 8, each in 01(6%) patient, complex karyotype in 5(28%) patients, del7q and hyperdiploidy each in 2(11%) patients. Two of the patients (11%) exhibited 3 way variant Ph translocations. We found lower median hemoglobin and platelet count and higher median eosinophil, basophil count and spleen size in patients with ACAs as compared to previously reported data. Our study also included the outcome of such patients followed at 6 and 18 months post treatment. Only 03 patients achieved major molecular response (MMR).
Conclusion
The main aim of the study was to highlight the importance of detecting ACAs in patients with CML at diagnosis. We also observed baseline characteristics and correlation of treatment response in such patients. As ACAs are reported to be associated with adverse outcomes and disease progression in literature, in this context our study would be valuable in adding additional information in local data
Session topic: 8. Chronic myeloid leukemia - Clinical
Keyword(s): Chronic myeloid leukemia, Cytogenetic abnormalities
Abstract: PB1962
Type: Publication Only
Background
Chronic myeloid leukemia (CML) is characterized by formation of Philadelphia (Ph) chromosome as a result of reciprocal translocation between chromosome 22 and 9 i.e. t(9;22)(q34;q11.2). Additional cytogenetic abnormalities ACAs are reported internationally in 5-12% newly diagnosed CML.
Aims
The study was done to observe the frequency of cytogenetic abnormalities in CML in addition to Ph chromosome at the time of diagnosis, their baseline hematological characteristics and correlate their outcome on follow up.
Methods
This was a cross sectional study carried out at the department of Cytogenetics and Molecular Pathology of National Institute of Blood Diseases and Bone Marrow Transplant Karachi Pakistan from May 2010 to September 2016.All the patients diagnosed with CML during the study period on the basis of morphological and cytogenetic analysis were included and observed for ACAs. Baseline cytogenetic analysis was performed on overnight, 24-hrs unstimulated and 72-hrs stimulated bone marrow cultures using standard procedures. The GTG (G-bands via trypsin using giemsa) banding technique was applied, karyotypes were described according to the International System for Human Cytogenetic Nomenclature (ISCN) 2013, karyogram were made using Metasystem ®. BCR-ABL1 by real-time quantitative PCR was done by QIAGEN kits on Rotor-Gene Q 5plex HRM instrument with 72-tubes rotor, at baseline and at 18 months of treatment performed on peripheral blood and bone marrow. MMR was defined as 03 log reduction from the baseline.
Results
Out of total 222 cases of CML,18(8.1%) patients revealed ACAs; we found –Y, double Ph chromosome and trisomy 8, each in 01(6%) patient, complex karyotype in 5(28%) patients, del7q and hyperdiploidy each in 2(11%) patients. Two of the patients (11%) exhibited 3 way variant Ph translocations. We found lower median hemoglobin and platelet count and higher median eosinophil, basophil count and spleen size in patients with ACAs as compared to previously reported data. Our study also included the outcome of such patients followed at 6 and 18 months post treatment. Only 03 patients achieved major molecular response (MMR).
Conclusion
The main aim of the study was to highlight the importance of detecting ACAs in patients with CML at diagnosis. We also observed baseline characteristics and correlation of treatment response in such patients. As ACAs are reported to be associated with adverse outcomes and disease progression in literature, in this context our study would be valuable in adding additional information in local data
Session topic: 8. Chronic myeloid leukemia - Clinical
Keyword(s): Chronic myeloid leukemia, Cytogenetic abnormalities