Contributions
Abstract: PB2041
Type: Publication Only
Background
According to the 2016 revision to the WHO classification of myeloid neoplasms and acute leukemia, the cases with rearrangement of tyrosine kinase (TK) genes PDGFRA, PDGFRB are classified in Myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB, or FGFR1, or with PCM1-JAK2. It is a rare event that patients presented rearrangements with these genes. And in the past decade, the dose of TKI to cases with PDGFRA and B abnormal was inconclusive.
Aims
The goal of the study was to assess the clinical and experimental characteristics and observe the response of Imatinib(IM) therapy of Myeloid/lymphoid neoplasms with PDGFRA or B abnormal.
Methods
Cytogenetic examination of bone marrow cells obtained from patients was performed by 24h culture method. R banding technical was used for karyotype analysis. PDGFRA and B gene rearrangement were detected by FISH using triple-color of 4q12 and dual color break-apart PDGFRB probes. The fusion genes of rearrangements of PDGFRA and B genes were detected by RT-PCR. Immunophenotype analysis was carried out by flow cytometry. Most of all cases were treated with IM and followed up
Results
The diagnoses included 27 cases of MPN, 1 case of AML-M2 and 1 case of non-hodgkin lymphoma. 21 cases were PDGFRA rearrangement, the other 8 were PDGFRB abnormal, 7 of 8 were EP fused gene, one of which concurrent with DEK-CAN fused gene, and the eighth had MYO18A-PDGFRB. 7 cases of the 8 PDGFRB rearrangement had a primary abnormality with t(5;12)(q33;p13) and the other one had a secondary abnormality of AML-M2. PDGFRA and B genes rearrangement detected by FISH and multiple-RT-PCR were positive. The immunophenotypical analysis showed myeloid or lymphoid. These cases achieve rapid and durable remissions on IM.
Conclusion
In summary, patients with significantly anemia and eosinophilia should be screened for the presence of PDGFRA and B rearrangements. The dual-colour FISH is a simple approach and should be added into the diagnostic work-up because these patients respond to imatinib therapy, and sustained responses have been observed. The OS of PDGFRA and B abnormal was similar with a previous report in a western population and another Chinese hematology center.
Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): PDGFRA, Myeloproliferative disorder, Tyrosine kinase inhibitor, PDGFRB
Abstract: PB2041
Type: Publication Only
Background
According to the 2016 revision to the WHO classification of myeloid neoplasms and acute leukemia, the cases with rearrangement of tyrosine kinase (TK) genes PDGFRA, PDGFRB are classified in Myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB, or FGFR1, or with PCM1-JAK2. It is a rare event that patients presented rearrangements with these genes. And in the past decade, the dose of TKI to cases with PDGFRA and B abnormal was inconclusive.
Aims
The goal of the study was to assess the clinical and experimental characteristics and observe the response of Imatinib(IM) therapy of Myeloid/lymphoid neoplasms with PDGFRA or B abnormal.
Methods
Cytogenetic examination of bone marrow cells obtained from patients was performed by 24h culture method. R banding technical was used for karyotype analysis. PDGFRA and B gene rearrangement were detected by FISH using triple-color of 4q12 and dual color break-apart PDGFRB probes. The fusion genes of rearrangements of PDGFRA and B genes were detected by RT-PCR. Immunophenotype analysis was carried out by flow cytometry. Most of all cases were treated with IM and followed up
Results
The diagnoses included 27 cases of MPN, 1 case of AML-M2 and 1 case of non-hodgkin lymphoma. 21 cases were PDGFRA rearrangement, the other 8 were PDGFRB abnormal, 7 of 8 were EP fused gene, one of which concurrent with DEK-CAN fused gene, and the eighth had MYO18A-PDGFRB. 7 cases of the 8 PDGFRB rearrangement had a primary abnormality with t(5;12)(q33;p13) and the other one had a secondary abnormality of AML-M2. PDGFRA and B genes rearrangement detected by FISH and multiple-RT-PCR were positive. The immunophenotypical analysis showed myeloid or lymphoid. These cases achieve rapid and durable remissions on IM.
Conclusion
In summary, patients with significantly anemia and eosinophilia should be screened for the presence of PDGFRA and B rearrangements. The dual-colour FISH is a simple approach and should be added into the diagnostic work-up because these patients respond to imatinib therapy, and sustained responses have been observed. The OS of PDGFRA and B abnormal was similar with a previous report in a western population and another Chinese hematology center.
Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): PDGFRA, Myeloproliferative disorder, Tyrosine kinase inhibitor, PDGFRB