High Risk Older AML Patients May be Benefited from the Treatment of Decitabine Combined Wih CAG Regimens

Patients over age 60 maked up more than 50% of newly diagnosed patients with acute myeloid leukemia (AML). Futhermore, with an aging population, more and more older AML patients were diagnosed in China. But the treatment approaches of this disease were variable, with many uncertainties and controversies. Treatment options for older patients with adverse prognostic features, such as poor performance status, unfavorable cytogenetics or an antecedent hematologic disorder were limited, and outcomes were poor. Aggres­sive induction chemotherapy had a high mortality and relatively low efficacy in this population. There were several new therapeutic schemes for older patients with AML. CAG regimens consisting of low-dose cytarabine, aclarubicin and granulocyte-colony stimulating factor for the treatment of older patients with AML showed higher rates of CR (42-68%). Decitabine, a DNA-hypomethylating agent induces differentiation and apoptosis of leukemic cells. The current National Comprehensive Cancer Care guidelines suggested decitabine as alterative options for older patients with AML. Previous studies have shown that decitabine demonstrated efficacy in a phase II multicenter study of older patients with AML, with a CR rate of 25%, 30-day mortality of 7%, median overall survival 7.7 months and little extramedullary toxicity. In our study, decitabine(15 mg/m2/d, d1-5) combined with CAG regimens (aclarubicin 20 mg/d, d3-6, Ara-C 10 mg/m2, q12h, d3-9, G-CSF 300ug, qd, d1-9) treated 27 older patients with AML, repeated every 4 weeks. Effectiveness and safety were assessed.

27 older patients with newly diagnosed AML who were in Tianjin First Central Hospital of China from January 2011 to December 2013 were enrolled in our study. They were all treated with decitabine combined with CAG regimens. The characteristics of the 27 patients were described in Table I. The study population included 15 males and 12 females, with a median age of 68 years (range 60-79 years). All patients had Eastern Cooperative Oncology Group (ECOG) performance status of <3. Cytogenetics were classified according to criteria of the Cancer and Leukemia Group B(CALGB), and were adverse in 11 patients (40.7%) and intermediate in 16 patients (59.3%). No patient had favorable cytogenetics. 12 patients (44.4%) had secondary AML or an antecedent MDS or myeloproliferative disorder. Molecular diagnostics with mutations of FLT3-ITD in 6 patients (22.2%), NPM1 in 7 patients (25.9%) patients and JAK-2 in 4 patients (14.8%). Clinical responses, survival and adverse events of all 27 patients were analyzed. The median treatment cycle was 4 cycles. Rate of complete remission, overall response rate and a 30-day mortality rate were 40.1%, 66.7%, 7.4%, respectively. The median overall survival and median recurrence-free survival were 13.0months (95%CI, 7.0-18.0 months ) and 7.0 months (95%CI, 3.0-11.0 months), respectively. Adverse events in the regimens were mainly included myelosuppression, infection, nausea, vomiting and liver dysfunction. The adverse events could be well tolerated after managements.

In conclusion, the treatment of decitabine combined with CAG regimens was found to be feasible and useful in high-risk older patients with AML. This regimen was a well-tolerated therapeutic alternative, was effective in producing remissions lasting several months or disease stabilization in high-risk older patients with AML.