title: The predictive value of early molecular response in chronic myeloid leukaemia patients treated with imatinib in a single real-world medical centre in a developing country.
abstract: BACKGROUND
  The prognosis of patients with chronic myeloid leukaemia (CML) has improved since the introduction of imatinib. However, patients who do not achieve complete cytogenetic response (CCyR) and major molecular response (MMR) have poorer prognosis. Recent clinical trials have demonstrated that early and deeper cytogenetic and molecular responses predict a better long-term outcome. This study aimed to analyse the relationship between early molecular response and clinical outcome in a real-life setting.
  
  
  METHODS
  This retrospective study included all patients with CML, in chronic or accelerated phase, who were treated with imatinib at University of Malaya Medical Centre, Malaysia.
  
  
  RESULTS
  A total of 70 patients were analysed. The median follow-up duration was 74 months, and the cumulative percentages of patients with CCyR and MMR were 80.0% and 65.7%, respectively. Overall survival (OS) and event-free survival (EFS) at ten years were 94.3% and 92.9%, respectively. Patients who achieved CCyR and MMR had significantly better OS and EFS than those who did not. At six months, patients who had a BCR-ABL level ≤ 10% had significantly better OS and EFS than those who had a BCR-ABL level > 10%. The target milestone of CCyR at 12 months and MMR at 18 months showed no survival advantage in our patients.
  
  
  CONCLUSIONS
  Our data showed that imatinib is still useful as first-line therapy. However, vigilant monitoring of patients who have a BCR-ABL level > 10% at six months of treatment should be implemented so that prompt action can be taken to provide the best outcome for these patients.
authors.affiliation: Department of Medicine, University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
authors.forename: Ping Chong
authors.initials: PC
authors.lastname: Bee
authors.affiliation: Department of Pathology, University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
authors.forename: Veera
authors.initials: V
authors.lastname: Sekaran
authors.affiliation: Department of Medicine, University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
authors.forename: Richard Rui Jie
authors.initials: RR
authors.lastname: Ng
authors.affiliation: Department of Medicine, University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
authors.forename: Ting Yi
authors.initials: TY
authors.lastname: Kweh
authors.affiliation: Department of Medicine, University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
authors.forename: Gin Gin
authors.initials: GG
authors.lastname: Gan
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D003582:Cytogenetics; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D016044:Fusion Proteins, bcr-abl / Q000378:metabolism; D006801:Humans; D000068877:Imatinib Mesylate / Q000627:therapeutic use*; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000175:diagnosis / Q000188:drug therapy* / Q000235:genetics*; D008296:Malaysia; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D016896:Treatment Outcome; D014495:Universities
chemical_list: D000970:Antineoplastic Agents; D000068877:Imatinib Mesylate; D016044:Fusion Proteins, bcr-abl
keywords: chronic myeloid leukaemia; complete cytogenetic response; early major molecular response; imatinib; survival