Jan Zuna; Lenka Hovorkova; Justina Krotka; Lucie Winkowska; Zbynek Novak; Lucie Sramkova; Jan Stary; Jan Trka; Giovanni Cazzaniga; Gunnar Cario; Marketa Zaliova | American Journal of Hematology | Oct 2023 | IF: 10,1 | doi.
Prof. MUDr. Jan Zuna, Ph.D, CLIP ＆ Department of Paediatric Haematology and Oncology, Second Faculty od Medicine and Motol University Hospital
Abstract
This study expands on previous findings regarding CML-like leukaemias that mimic chronic myeloid leukaemia in lymphoid blast crisis, highlighting clinical features and differences from typical Ph+ acute lymphoblastic leukaemia (ALL) in children. Our observations align with recent adult studies, particularly emphasizing the significance of long-term low BCR::ABL1 positivity in the absence of IG/TR rearrangements, which raises questions about the efficacy of tyrosine kinase inhibitor (TKI) therapy. We report a similar case of persistent low-level BCR::ABL1 positivity following TKI withdrawal, suggesting the continued risk of relapse from IG/TR-negative/BCR::ABL1-positive cell reservoirs. Notably, recent relapses in BCR::ABL1-positive ALL patients, initially classified as having CML-like disease, indicate the development of new leukaemic clones, underscoring the need for vigilant monitoring of both BCR::ABL1 and IG/TR rearrangements post-treatment. We recommend routine molecular monitoring following treatment to better assess patient outcomes and treatment responses while considering individual sensitivity in analysis methods. Continuous evaluation could inform treatment strategies, especially in paediatric settings where stem cell transplantation remains an option in cases of recurrence.
