Trends in acute myeloid leukaemia in Western Australia over time: Improved outcomes with contemporary management

Introduction: Real-world survival in acute myeloid leukaemia (AML) is poor, and there has been little change to the intensive induction and consolidative chemotherapy regimens over 30 years. Despite this, there have been developments in therapeutic agents for patients unfit for intensive therapy, supportive care, risk stratification and allogenic stem cell transplant. We report outcomes of these patients with AML treated using contemporary care standards in Western Australia (WA) and compare this with a historical cohort. Methods: AML diagnosed between 2009-2018 in WA were identified by discharge diagnosis at 3 tertiary public hospitals in Perth and the database of the state reference cytogenetic laboratory at Pathwest. Medical and laboratory records were reviewed retrospectively for characteristics and outcomes. Comparison was made with a historical cohort diagnosed 1991-2015 and analysed with t-test and Kaplan-Meier methods. Results: 734 patients were identified in the contemporary period. Median age was 64.4 years and 70% were primary/de novo AML. 61% were managed with intensive chemotherapy and 16.9% of these under the age of 60proceeded to allogeneic stem cell transplant in first remission. There were no significant differences in the rates of intensive therapy or allogenic transplantation compared with the historical cohort. 98.8% of patients had successful cytogenetic studies performed. Of those with a normal karyotype, molecular studies were performed in 57%. Median overall survival in patients treated intensively was 56.6 months for age 60 or less, and 10 months in patients age over60. Cytogenetic risk group predicted survival (p<0.0001). Survival was significantly improved in both groups treated intensively and non-intensively compared with the historical cohort; 18.7 vs 13.2 months (HR 1.348, 95% CI 1.157-1.571) and 3.1 vs 1.6 months (HR 1.431, 95% CI 1.1223-1.674) respectively. Conclusion: Survival has improved in all patients with AML in WA over time despite no significant change to intensive chemotherapy regimens. This may be explained by improved risk stratification, supportive care, nonintensive therapy options, and allogeneic donor selection and transplantation techniques.