Loading
9 slides generated from the cancer page, with a quiz from the open benchmark and speaker notes that cite the sources. Arrow keys move between slides; Print gives one slide per page.
Philadelphia chromosome-positive leukaemia carries the same faulty BCR::ABL1 gene as chronic myeloid leukaemia. Until 2000 most children with it needed a bone marrow transplant; adding the targeted pill imatinib to chemotherapy, and then dasatinib, means most are now cured without one.
The t(9;22) translocation fuses BCR to ABL1 and makes a constitutively active tyrosine kinase; in ALL the fusion is usually the p190 form. Before kinase inhibitors, Ph-positive childhood ALL had the worst outcome of any subtype, with event-free survival around a quarter to a third on chemotherapy alone, and allogeneic transplant from a matched sibling in first remission was standard. Imatinib, approved for chronic myeloid leukaemia in 2001, was taken into childhood ALL by the Children's Oncology Group in AALL0031: given continuously with intensive chemotherapy, it produced a three-year event-free survival of 80 percent in the highest-exposure cohort against about 35 percent in historical controls, and no advantage for transplant over chemotherapy plus imatinib. The European EsPhALL trials confirmed that continuous imatinib beat intermittent dosing, and imatinib was approved for children with newly diagnosed Ph-positive ALL in 2013.
Dasatinib is more potent and crosses into the cerebrospinal fluid. AALL0622 combined it with the AALL0031 backbone and dropped cranial irradiation without excess central nervous system relapse; CA180-372, the registration trial, gave three-year event-free survival of 65.5 percent and overall survival of 91.5 percent with dasatinib and EsPhALL chemotherapy, and dasatinib was approved for children with Ph-positive ALL in December 2018. The Chinese Children's Cancer Group randomised 189 children directly between imatinib and dasatinib on the CCCG-ALL-2015 backbone: four-year event-free survival 71.0 percent with dasatinib against 48.9 percent with imatinib, overall survival 88.4 percent against 69.2 percent, and fewer central nervous system relapses. Transplant is now reserved for children with a poor residual disease response or persistent disease after consolidation.
| Setting | Approach | Guideline |
|---|---|---|
| Newly diagnosed | Imatinib or dasatinib started in induction and continued throughout intensive BFM or EsPhALL-type chemotherapy; intrathecal therapy without cranial irradiation. | not mapped |
| Poor residual disease response | Blinatumomab to clear residual disease, then allogeneic transplant in first remission with a kinase inhibitor continued afterwards. | not mapped |
| Relapsed or refractory | Switch kinase inhibitor by mutation (ponatinib for T315I, used off label in children), blinatumomab or CD19 CAR T-cells, inotuzumab ozogamicin, then transplant. | not mapped |