The silent players: Atypical BCR‑ABL isoforms as biomarkers and therapeutic hurdles in CML pathogenesis (Review). (PubMed, Oncol Rep)
Tyrosine kinase inhibitors (TKIs), including imatinib and dasatinib, remain cornerstone treatments; however, marked inter‑variant heterogeneity in TKI responsiveness is observed: Patients harboring e13a3/e14a3 transcripts generally show favorable prognoses, while those with e1a3/e6a2 variants demonstrate an increased risk of relapse and/or TKI resistance, often requiring multimodal strategies combining chemotherapy or allogeneic hematopoietic stem cell transplantation. Despite advances in elucidating the clinical implications of fusion gene heterogeneity in leukemogenesis, the prognostic value of atypical BCR‑ABL1 isoforms requires further validation through multicenter studies with extended cohorts. This review aimed to summarize cases of atypical fusion genes in CML, with analysis of clinical characteristics, therapeutic interventions, and prognostic outcomes, to provide clinicians with enhanced reference material for improved patient management.