Clinical Case Discussion Forum
To share and enhance best practice management of CML, experts and interested clinicians can discuss difficult or interesting CML cases here. Physicians submit a brief history of the patient and the case for discussion using this forum.
CML blast phase (MPAL) - aloSCT
Dear Colleagues,
I would like to consult my young patient (now age 23), actually after 2 x cycles of CHT for MPAL after BCR:ABL positive CML (MPAL was diagnosed in DEC 2025 after 1,5 year of TKI treatment IMA, DASA and PONA, TKI resistance, no BCR::ABL mutation detected, RUNX 1 posit.).
Now, in hematologic remission, BCR::ABL 4% positive on qPCR, BM flowcytometry MRD posit. 0,4% B-lymphoblasts and no MPAL blastic cells. Because of CNS infiltration i.t. CHT a CNS radiotherapy was given, now it ok.
We plan aloSCT with HLA matched brother. Which conditioning do you prefer in this case please? BUCY2 or ALL like conditioning or other? Thank you!
Dr. Slezáková, University Hospital Bratislava.
It is not clear if the patient is currently taking a TKI while waiting for transplant. I am assuming that her blast crisis occurred on ponatinib so this would not be ideal. The remaining options, assuming availability in Slovakia, are Asciminib, olverembatinib and Enliven. The latter two may have to be obtained through a named patient program or a clinical trial. I am discussing this here, not because they would be an alternative to transplant but for consideration after the transplant.
For a young patient in second chronic phase, we would always recommend a myeloablative conditioning regimen. The precise regimen is unimportant with respect to her CML. We would use CyTBI but BuCy would also be acceptable.
Very difficult case and I do not think there is much in the way of randomized data to help decide the choice of conditioning. Personally, I have always preferred a radiation based regimen for diseases like this, but much of this would depend on the XRT given beforehand. I would presume that he received 12-24 Gy to the brain +/- spinal cord. If 12, then I would think CyTBI with 4 days Cy at 50 mg/kg and 12Gy in 6 fractions over 3 days. You have less room with 24 Gy and I would think FluByTBI with 4 days of Flue at 30mg/kg, 2 days Cy at 60mg/kg and TBI 4Gy in 2 fractions taking a very aggressive approach.
What is more important is a quick discontinuation of GVHD prophylaxis starting by day 60 if no GVH and stopping within a month. I would also give strong consideration to starting TKI again once immunosuppression has been discontinued. As I am typing this I see that Jane has made a comment about choice of TKI. If he became acute on PON, then not the choice and although there is not a lot of evidence with this kind of advanced disease, one of the others. If however remission was achieved with chemo and PON, then I would go with PON 30 post for 2-3 years.