Purpose: Tyrosine kinase inhibitors (TKIs) have improved the prognosis of chronic myeloid leukaemia (CML), allowing patients with favourable disease profiles and molecular responses to attempt treatment-free remission (TFR). We aim to establish the relapse-free survival (RFS) outcomes and identify prognostic factors for successful remission maintenance among those who attempt TFR. Methods: Adult CML patients who had undergone TFR from January 1, 2016, to June 30, 2024, were included. Upon TKI discontinuation, real-time quantitative polymerase chain reaction (RQ-PCR) was monitored monthly for the first 12 months, then every 3 months, with TKI reinitiated upon a transcript level above 0.1% (IS). Data analysis was performed using SPSS version 29.0 (SPSS Inc., Chicago, IL, USA). Results: Fifty-seven patients (27 males and 30 females) with a median age of 46 years (range 16 – 70) were analysed.The majority had a low EUTOS long-term survival (ELTS) score (61.4%, n = 35) and received imatinib (87.7%, n = 50).The median treatment duration was 8.8 years (range 4.2 – 18.8), and the median duration for sustained deep molecular remission (DMR) was 4.6 years (range 2.1 – 11.1). RFS was 70.2% at 6 months, 62.5% at 12 months and 56.8% at 2 years after a median follow-up of 34 months (range 9 – 101). The MR5 level was identified as an independent factor associated with sustained remission. All relapsed patients achieved DMR upon treatment reinitiation. Conclusion Treatment discontinuation can be safely performed, with many achieving long-term treatment-free remission. A deeper molecular response (MR5) is associated with an improved likelihood of remission maintenance.

Background: With the emergence of tyrosine kinase inhibitors and the incorporation of stringent measurable residual disease (MRD) monitoring, risk stratification for BCR-ABL1-positive acute lymphoblastic leukemia (ALL) patients has changed significantly. However, whether this monitoring can replace conventional risk factors in determining whether patients need allogeneic stem cell transplantation is still unclear. This study aimed to determine the impact of BCR-ABL1 monitoring on the outcome of patients with BCR-ABL1-positive ALL after allogeneic stem cell transplantation. Methods: We retrospectively analyzed the survival outcome of patients with BCR-ABL1-positive ALL based on the quantification of BCR-ABL1 at 3 timepoints: the end of induction (timepoint 1), post-consolidation week 16 (timepoint 2), and the end of treatment for patients who were either transplant-eligible or non-transplant eligible (timepoint 3). Results: From 2006 to 2018, a total of 96 patients newly diagnosed with BCR-ABL1-positive ALL were treated with chemotherapy and tyrosine kinase inhibitors. Thirty-eight (41.3%) patients achieved complete remission, and 33 patients underwent allogeneic stem cell transplantation. Our data showed that pre-transplant MRD monitoring by real-time quantitative polymerase chain reaction had the highest correlation with survival in patients with BCR-ABL1-positive ALL, especially for those who underwent allogeneic stem cell transplantation. Conclusion Patients without MRD pre-transplantation had superior survival compared with those who had MRD, and they had excellent long-term outcomes after allogeneic stem cell transplantation.

Background: With the emergence of tyrosine kinase inhibitors and the incorporation of stringent measurable residual disease (MRD) monitoring, risk stratification for BCR-ABL1-positive acute lymphoblastic leukemia (ALL) patients has changed significantly. However, whether this monitoring can replace conventional risk factors in determining whether patients need allogeneic stem cell transplantation is still unclear. This study aimed to determine the impact of BCR-ABL1 monitoring on the outcome of patients with BCR-ABL1-positive ALL after allogeneic stem cell transplantation. Methods: We retrospectively analyzed the survival outcome of patients with BCR-ABL1-positive ALL based on the quantification of BCR-ABL1 at 3 timepoints: the end of induction (timepoint 1), post-consolidation week 16 (timepoint 2), and the end of treatment for patients who were either transplant-eligible or non-transplant eligible (timepoint 3). Results: From 2006 to 2018, a total of 96 patients newly diagnosed with BCR-ABL1-positive ALL were treated with chemotherapy and tyrosine kinase inhibitors. Thirty-eight (41.3%) patients achieved complete remission, and 33 patients underwent allogeneic stem cell transplantation. Our data showed that pre-transplant MRD monitoring by real-time quantitative polymerase chain reaction had the highest correlation with survival in patients with BCR-ABL1-positive ALL, especially for those who underwent allogeneic stem cell transplantation. Conclusion Patients without MRD pre-transplantation had superior survival compared with those who had MRD, and they had excellent long-term outcomes after allogeneic stem cell transplantation.