Validation of AML-Score in Older Adults Receiving CPX-351 Intensive Induction Chemotherapy for Treatment of Secondary Acute Myeloid Leukemia

Abstract Microabstract : The AML-Score is a web-based tool that was designed to predict the risk of complete remission and early mortality in older patients with acute myeloid leukemia being treated with traditional induction chemotherapy. This retrospective study of 40 patients assesses the validity of the AML-Score in a cohort of older patients with secondary AML who received induction chemotherapy with the newer agent, CPX-351. Results of the study show that the AML-Score trends in the correct direction for predicting CR and EM in this patient population and may facilitate oncologist decision making when considering treatment with CPX-351. Introduction/Background : The AML-Score has been validated in patients receiving traditional induction chemotherapies but not CPX-351. We conducted a retrospective analysis to evaluate, among patients with secondary acute myeloid leukemia who received intensive induction with CPX-351, if the AML-Score associates with 1) complete remission (CR) and 2) early mortality (EM) within 60 days of induction. Materials and Methods : We abstracted demographic and clinical data from consecutive patients receiving CPX-351 at Sidney Kimmel Cancer Center at Thomas Jefferson University Hospital between September 2017 and November 2020. We used descriptive statistics and receiver operating curves to evaluate the relationship between AML-Score and rates of CR and EM. Results : In total, 40 patients were included. 27 (67.5%) were male, 27 (67.5%) were white, 36 (90.0%) were not Hispanic or Latino, and 29 (72.5%) were aged ≥60 years. Twenty-seven patients (67.5%) had a CR, and 4 (10%) experienced EM. Observed rates of CR and EM generally increased with increasing predicted risk. The area under the curve was 0.75 (95% CI 0.60-0.90) for CR and 0.82 (95% CI 0.68-0.96) for EM. Conclusion : The AML-Score tool trends in the correct direction for predicting CR and EM, and thus may facilitate oncologist prognostication and treatment planning for patients receiving CPX-351. However, its clinical utility is limited by its underestimation of the risk of CR and overestimation of the risk of EM. Further validation in a larger cohort is needed to calculate accurate point estimates of CR and EM risk in this population.