All the newly diagnosed nonM3 AML patients referred to Shahid Ghazi Tabatabai Hospital, Tabriz, Iran, in 4 years (2017–2021) were included in this study. We determined the sample size with the reasoning that all newly diagnosed patients with non-ALM3 were included, in accordance with the study conducted by Raisi et al.(13)The study protocol was approved by the ethics committee of Tabriz University of Medical Sciences (IR.TBZMED.REC.1400.442). Patients’ disease had been confirmed by flow-cytometry of bone marrow samples. Patients diagnosed with acute lymphoblastic leukemia (ALL) and acute promyelocytic leukemia (APL) were not considered in this study.
A standardized treatment plan was applied to all patients. This started with induction therapy using a 3 + 7 regimen (daunorubicin at 45 mg/m² and cytosine arabinoside at 100 mg/m²), followed by two cycles of a 5 + 2 regimen after remission (daunorubicin at 45 mg/m² for 2 days, and cytosine arabinoside at 100 mg/m² for an additional 5 days). For patients who did not achieve CR morphologically after the first round of induction chemotherapy, treatment was escalated with cytosine arabinoside at 500 mg/m² administered via slow intravenous push twice daily for 7 days, along with Novantrone at 12 mg/m² daily for 3 days.
Bone marrow samples stored in anticoagulant ethylenediaminetetraacetic acid (EDTA) tubes were prepared as a suspension. Operating with a cytochemistry technique with a H1 autoanalyzer (Technicon, USA) cell counts were performed. Leukocyte numbers adjusted to between 5,000 and 10,000 cells per microliter. After that samples were stained directly with antibodies (monoclonal) conjugated with fluorescent markers. Flowcytometry was performed using BD FACS callibur device and cell guest software and dedicated panel was used directly against specific antigens, especially CD38, CD64, CD33, CD117, and HLA DR. A 20% threshold was set to determine cases positive for CDs.
After achieving CR, the patients were monitored monthly during the first year and then annually. The primary outcomes of interest were overall survival (OS) and one-year survival. OS was outlined as the duration from the AML diagnosis to either leukemia caused death or the last follow-up date (December 2021).
The normality of the baseline patient characteristics was evaluated utilizing a skewness test, and the based on the outcomes, the data were presented as counts and percentages or as mean (± SD). To categorize quantitative values, median values were computed and used as thresholds to distinguish between high and low expression levels. The following points were applied for other parameters: hemoglobin, < 8 and ≥ 8 g/dL; WBC, < 4,000 and ≥ 4,000 /mm3; Neutrophil < 100 and ≥ 100 /mm3; and platelets, < 50,000 and ≥ 50,000 /mm3.
For the survival analyses, we utilized the Kaplan–Meier method along with log-rank tests to evaluate the prognostic effects of CD38, CD64, CD117, CD33, and HLA DR expressions on AML patients, independently. Additionally, Cox proportional hazards regression analysis was carried out to determine the 95% confidence intervals (CIs), standard errors, and hazard ratios (HRs) for the prognostic factors.
The worth of the prognostic indexes on OS and one-year survival was assessed using the Kaplan–Meier method and log-rank tests. Using STATA 11.0. a p-value of ≤ 0.05 was deemed statistically significant.