SOHO State of the Art Updates and Next Questions | Approach to BCR::ABL1-Like Acute Lymphoblastic Leukemia

Philadelphia-like (Ph-like) or BCR::ABL1-like acute lymphoblastic leukemia (ALL) is a common high-risk subtype of B-cell precursor ALL (B-ALL) characterized by a diverse range of genetic alterations that challenge diagnose and converge on distinct kinase and cytokine receptor-activated gene expression profiles, resembling those from BCR::ABL1-positive ALL from which its nomenclature. The presence of kinase-activating genetic drivers has prompted the investigation in preclinical models and clinical settings of the efficacy of tyrosine kinase inhibitor (TKI)-based treatments. This was further supported by an inadequate response to conventional chemotherapy, high rates of induction failure and persistent measurable residual disease (MRD) positivity, which translate in lower survival rates compared to other B-ALL subtypes. Therefore, innovative approaches are underway, including the integration of TKIs with frontline regimens and the early introduction of immunotherapy strategies (monoclonal antibodies, T-cell engagers, drug-conjugates, and CAR-T cells). Allogeneic hematopoietic cell transplantation (HSCT) is currently recommended for adult BCR::ABL1-like ALL patients in first complete remission. However, the incorporation of novel therapies, a more accurate diagnosis and a more sensitive MRD assessment may modify the risk stratification and the indication for transplant in these patients.