Immunophenotypic characteristics and prognosis of adult patients with initial treatment of acute myeloid leukemia

Objective To investigate the immunophenotypic characteristics of adult patients with initial treatment of acute myeloid leukemia (AML), as well as its relationship with curative effect. Methods A total of 167 adult patients with initial treatment of AML were randomly selected by computer generated random number method from January 2013 to December 2016 in Zibo Central Hospital of Shandong Province. Monoclonal antibody direct immunofluorescence labeling was used to label AML cell antigens of patients. The immunophenotypes of myeloid cell lines, lymphoid cell lines, and hematopoietic stem/progenitor cells of patients′ AML cells were analyzed by tricolor flow cytometry two-parameter scatter plot with CD45/side scatter (SSC). All AML patients were treated with conventional induction chemotherapy. After 1 course of chemotherapy, complete remission (CR) rates of patients were observed. The CR rates of AML patients of different immunophenotype were compared using χ2 test. The study protocol was approved by the Ethical Review Board of Investigation in Human Being of Zibo Central Hospital (Approval No. 2013-9). Informed consent was obtained from each participant. Results ① Among 167 adult patients with initial treatment of AML in this study, myeloid cell lines related antigens of positive expression rates from high to low were as follows: CD33 (90.4%, 151/167), CD13 (87.4%, 146/167), CD117 (79.0%, 132/167), myeloperoxidase (MPO) (71.3%, 119/167), CD64 (31.7%, 53/167), CD14 (21.6%, 36/167) and CD71 (4.2%, 7/167). The positive expression rates of CD14 and CD64 in 33 AML-M4 patients and 40 AML-M5 patients were high. The positive expression rates of CD14 and CD64 in AML-M4 patients were 24.2% (8/33) and 48.5% (16/33), respectively. And the positive expression rates of CD14 and CD64 in AML-M5 patients were 62.5% (25/40) and 77.5% (31/40), respectively. CD71 expressions were all positive in 5 AML-M6 patients. ② The hematopoietic stem/progenitor cells related antigens of positive expression rates from high to low in 167 adult patients with initial treatment of AML were as follows: CD38 (89.8%, 150/167), human leukocyte antigen (HLA)-DR (58.7%, 98/167), and CD34 (57.5%, 96/167). The positive expression rates of CD34 and HLA-DR were low in 34 AML-M3 patients, which were 5.9% (2/34) and 8.8% (3/34), respectively. ③ The lymphoid cell lines related antigens of positive expression rates from high to low in 167 adult patients with initial treatment of AML were as follows: CD7 (20.4%, 34/167), CD19 (13.8%, 23/167), CD4 (7.2%, 12/167), CD2 (4.2%, 7/167), CD10 (1.8%, 3/167), CD22 (1.2%, 2/167) and CD20 (0.6%, 1/167). ④ In all 167 adult patients with initial treatment of AML, 103 patients achieved CR with a CR rate of 61.7% after the first induction chemotherapy. In 133 patients with non-AML-M3 subtype, CR rates of AML patients with CD7 and CD34 positive expression were 51.5% (17/33) and 45.7% (43/94), which were lower than those of negative expression patients with CR rates of 72.0% (72/100) and 69.2% (27/39), and the differences were statistically significant (χ2=4.703, P=0.030; χ2=6.099, P=0.014). The CR rates of AML patients with MPO and CD19 positive expression were 71.3% (62/87) and 69.6% (16/23), which were higher than those of negative expression patients with CR rates of 47.8% (22/46) and 46.4% (51/110), and the differences were statistically significant (χ2=7.104, P=0.008; χ2=4.096 , P=0.043). Conclusions CD33, CD13, CD117 and MPO are common immune markers of adult patients with initial treatment of AML. CR rates after the first induction chemotherapy of adult patients with initial treatment of AML expressing CD7 and CD34 positive, are lower than those of negative ones, and CR rates of patients with positive expression of MPO and CD19 are higher than those of negative ones. Immunophenotype has great significance for the diagnostic classification and prognosis of AML. Key words: Leukemia, myeloid, acute; Immunophenotyping; Drug therapy; Prognosis; Treatment outcome; Flow cytometry; Adult