Correlation Between Rebound Thrombocytosis And Prognosis In Patients With Acute Myeloid Leukemia After First Induction Chemotherapy

Objective To investigate the relationship among the rebound thrombocytosis after the first induction chemotherapy,clinical characteristics,and prognosis of patients with acute myeloid leukemia,to assess the value of the rebound thrombocytosis after the first chemotherapy as a prognostic indicator in AML.Methods A total of 116 newly diagnosed patients with non-acute promyelocytic acute myeloid leukemia who were hospitalized in the Department of Hematology of the First Hospital of Lanzhou University from June 2015 to September 2019 were retrospectively selected.We investigated whether the platelet count after the first induction chemotherapy is a prognostic factor for AML,and then grouped the patients according to platelet count after the first induction chemotherapy and compared with other factors affecting the prognosis of patients with acute myeloid leukemia by univariate and multivariate regression analysis.Results（1）The Univariate analysis of the prognosis of acute myeloid leukemia showed significant differences in OS（statistical value=9.221,P=0.002）and EFS（statistical value=8.909,P=0.003）between acute myeloid leukemia patients with platelet count>300×10⁹/L and≤300×10⁹/L after the first induction chemotherapy,and the age,white blood cell count at initial diagnosis,chromosome,FLT3-ITD mutation,CEBPA double mutation,TP53 mutation,and remission after the first induction chemotherapy were also factors affecting the prognosis of AML patients（P<0.05）.（2）Univariate factors with P<0.1 were included in the Cox model for multivariate regression analysis,and the results showed that:age≥60 years（HR=2.488,95%CI1.207-5.127,P=0.014）,complex karyotype（HR=0.144,95%CI 0.052-0.397,P=0.000）,incomplete remission after the first induction（HR=2.551,95%CI 1.295-5.027,P=0.007）,and platelet count≤300×10⁹/L after the first induction chemotherapy（HR=2.857,95%CI 1.175-6.944,P=0.021）were independent risk factors affecting OS in AML patients;age≥60 years（HR=2.211,95%CI 1.074-4.552,P=0.031）,complex karyotype（HR=0.165,95%CI 0.059-0.462,P=0.001）,and incomplete remission after the first induction chemotherapy（HR=4.097,95%CI 1.966-8.537,P=0.000）,and platelet count≤300×10⁹/L after the first induction chemotherapy（HR=2.619,95%CI 1.070-6.406,P=0.035）were independent risk factors affecting EFS in AML patients.（3）The optimal cut-off value for rebound thrombocytosis after the first induction chemotherapy to predict patient prognosis was 330×10⁹/L,that is,RT₃₃₀（sensitivity 0.935,specificity 0.878,P=0.002）.（4）patients with RT₃₃₀ after the first induction chemotherapy had lower white blood cell count at initial diagnosis,FLT3-ITD mutation rate,the proportion of poor prognostic stratification,recurrence rate,and mortality,as well as higher NPM1 mutation rate without FLT3-ITD,CEBPA double mutation rate without FLT3-ITD,the proportion of good prognostic stratification,and CR rate than patients without RT₃₃₀（P<0.05）.（5）The overall survival（OS）and event-free survival（EFS）time of patients with platelet count<330×10⁹/L after chemotherapy were 30 and 26 months,and the difference was statistically significant（P=0.003）,that is,RT₃₃₀ patients had a better prognosis and were an independent factor for good prognosis in AML patients（OS:HR=0.393,95%CI 0.870-6.676,P=0.018;EFS:HR=0.402,95%CI 0.869-6.531,P=0.021）.Conclusion（1）The rebound thrombocytosis after the first induction chemotherapy is an independent factor indicating the good prognosis of patients with acute myeloid leukemia.（2）Patients with RT₃₃₀30 after the first induction chemotherapy had a better prognosis,the RT₃₃₀ was an independent factor for good prognosis,and the platelet counts at initial diagnosis were relatively reduced.（3）The occurrence of RT₃₃₀is associated with factors indicating a good prognosis in AML that has been recommended by the NCCN guidelines.