Contributions
Abstract: PB1523
Type: Publication Only
Session title: Chronic myeloid leukemia - Clinical
Background
Chronic myeloid leukemia (CML) is a myeloproliferative disorder. It is very rare during childhood. Tyrosine kinase inhibitors (TKI) changed those patients’ treatment approach and prognosis. The most of the authors are in consensus to TKIs should be the first line treatment in CML patients. However, in children and young adults it may be concern. Although Bone Marrow Transplantation (BMT) is a curative approach, TKIs should continue as a life- long treatment.
Aims
In this single center series we aimed to evaluate the presenting symptoms, findings, treatment approaches, responses and prognosis of children with CML under the treatment of TKIs.
Methods
Single center retrospective study was approved by Local Ethic Committee. CML patients who were diagnosed at Ege University Pediatric Hematology Department between 1997 and 2020 were evaluated.
Results
Sixteen patients were diagnosed with CML during the study period. The median age of the patients was 9,5years (range 2-16 years), nine of them were girls.
5 patients were in blastic phase, 11 patients were in chronic phase of CML.
The predominant symptoms at presentation were asthenia (31%) and fever(31%). The most predominant clinical sign was splenomegaly (80% ). The fever was seen in all patients in blastic phase. The mean WBC count at presentation was 205.000/mm3. 50% of the patients the WBC count was above 200.000/mm3. Only one patient with normal WBC count who was investigated for the reasons of thrombocytosis (1.820.000/mm3) was diagnosed as CML.
Hydroxyurea treatment was given before the translocation (9;22) had been detected. One patient was given ARA-C and Interferon for 4 years since imatinib was not available. Imatinib treatment was given 15 patients as initiation treatment. Complete hematological response was documented in all patients between 20 and 68 days (median33 days ) of treatment. The major molecular response was achieved in 14 of the patients within 6 months. Five patients with blastic crisis received both ALLIC BFM 2002 Chemotherapy protocol and imatinib.
7 patients received only imatinib. In 7 patients imatinib was switched to dasatinib as second line therapy. In 2 Patients nilotinib was started as third line treatment.
Two patients underwent BMT. The first patient achieved MMR at 12 months, but showed molecular relapse at 14 months of follow up, and the second patient developed blastic crisis at the 19 month of imatinib treatment.
TKI treatment was discontinued in 5 patients after a median of 7 years (range 5-10.5 years) treatment. Three of the patients were in MMR for seven years and one for 10,5 years. While no molecular relapse was seen until the last follow up, the median follow up period was 70 months. One patient who was on MMR for 5 years, molecular relapse developed nine months after the discontinuation of the treatment. TKI treatment was restarted.
The median follow up of whole study group is 109 months (range 19-522 months) and overall survival is 100%. BMT is needed in 2 patients (12.5%). Additionally 3 patients (18,7%) received only TKIs and succeded to discontinue TKIs without molecular relapse for a median period of 163 months.
Conclusion
In Conclusion, CML is a very rare disease during childhood. TKIs lead very good results in survival. In some patients, it is possible to discontinue TKIs without molecular relapse.
Keyword(s): Chronic myeloid leukemia, Tyrosine kinase inhibitor
Abstract: PB1523
Type: Publication Only
Session title: Chronic myeloid leukemia - Clinical
Background
Chronic myeloid leukemia (CML) is a myeloproliferative disorder. It is very rare during childhood. Tyrosine kinase inhibitors (TKI) changed those patients’ treatment approach and prognosis. The most of the authors are in consensus to TKIs should be the first line treatment in CML patients. However, in children and young adults it may be concern. Although Bone Marrow Transplantation (BMT) is a curative approach, TKIs should continue as a life- long treatment.
Aims
In this single center series we aimed to evaluate the presenting symptoms, findings, treatment approaches, responses and prognosis of children with CML under the treatment of TKIs.
Methods
Single center retrospective study was approved by Local Ethic Committee. CML patients who were diagnosed at Ege University Pediatric Hematology Department between 1997 and 2020 were evaluated.
Results
Sixteen patients were diagnosed with CML during the study period. The median age of the patients was 9,5years (range 2-16 years), nine of them were girls.
5 patients were in blastic phase, 11 patients were in chronic phase of CML.
The predominant symptoms at presentation were asthenia (31%) and fever(31%). The most predominant clinical sign was splenomegaly (80% ). The fever was seen in all patients in blastic phase. The mean WBC count at presentation was 205.000/mm3. 50% of the patients the WBC count was above 200.000/mm3. Only one patient with normal WBC count who was investigated for the reasons of thrombocytosis (1.820.000/mm3) was diagnosed as CML.
Hydroxyurea treatment was given before the translocation (9;22) had been detected. One patient was given ARA-C and Interferon for 4 years since imatinib was not available. Imatinib treatment was given 15 patients as initiation treatment. Complete hematological response was documented in all patients between 20 and 68 days (median33 days ) of treatment. The major molecular response was achieved in 14 of the patients within 6 months. Five patients with blastic crisis received both ALLIC BFM 2002 Chemotherapy protocol and imatinib.
7 patients received only imatinib. In 7 patients imatinib was switched to dasatinib as second line therapy. In 2 Patients nilotinib was started as third line treatment.
Two patients underwent BMT. The first patient achieved MMR at 12 months, but showed molecular relapse at 14 months of follow up, and the second patient developed blastic crisis at the 19 month of imatinib treatment.
TKI treatment was discontinued in 5 patients after a median of 7 years (range 5-10.5 years) treatment. Three of the patients were in MMR for seven years and one for 10,5 years. While no molecular relapse was seen until the last follow up, the median follow up period was 70 months. One patient who was on MMR for 5 years, molecular relapse developed nine months after the discontinuation of the treatment. TKI treatment was restarted.
The median follow up of whole study group is 109 months (range 19-522 months) and overall survival is 100%. BMT is needed in 2 patients (12.5%). Additionally 3 patients (18,7%) received only TKIs and succeded to discontinue TKIs without molecular relapse for a median period of 163 months.
Conclusion
In Conclusion, CML is a very rare disease during childhood. TKIs lead very good results in survival. In some patients, it is possible to discontinue TKIs without molecular relapse.
Keyword(s): Chronic myeloid leukemia, Tyrosine kinase inhibitor