Siew Lian ChongProf. Madya Dr. Asral Wirda Binti Ahmad AsnawiTze Shin LeongJenq Tzong TanKian Boon LawSiong Leng HonRui Jeat FannSen Mui Tan2024-05-272024-05-2720212022-1-27Chong, Siew & Asnawi, Asral & Leong, Tze & Tan, Jenq & Law, Kian Boon & Hon, Siong & Rui Jeat, Fann & Tan, Sen Mui. (2021). Impact of timely BCR-ABL1 monitoring before allogeneic stem cell transplantation among patients with BCR-ABL1 -positive B-acute lymphoblastic leukemia. BLOOD RESEARCH. 56. 10.5045/br.2021.2021045.2288-0011597-23https://doi.org/10.5045/br.2021.2021045https://www.bloodresearch.or.kr/journal/view.html?doi=10.5045/br.2021.2021045https://oarep.usim.edu.my/handle/123456789/3179Blood Res 2021; 56(3): 175-183 https://doi.org/10.5045/br.2021.2021045Background 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.enALL, BCR-ABL1, Philadelphia, Survival, TKIArticle175183563