Abstract
Context Acute myeloid leukemia (AML) exhibits one of the therapeutic challenges to the clinician owing to unsatisfactory outcomes obtained by conventional chemotherapy protocols. Immune checkpoints have gained attention in the recent years in the field of oncology as a presumable mechanism of cancer to evade immunity, but their status in AML has yet to be investigated. Aims The aim was to measure programmed death ligand-1 (PDL-1) expression on the blast cells in patients with de novo AML at time of diagnosis, followed by investigating its relationship to different patients' characteristics as well as disease prognostic variables and therapy outcomes. Setting and design A total number of 40 adult patients with de-novo AML were recruited. Materials and methods Surface expression of PDL-1 on the blast cells was evaluated by multicolor flow cytometry. The collected data were revised, coded, tabulated, and introduced to a PC using IBM SPSS version 20.0. Results PDL-1 has been expressed amongst the study cohort with a mean expression of 43.0124.72. PDL-1 expression was not different among different risk categories of the disease and did not influence the therapeutic response. Despite a higher PDL-1 expression in refractory cases in comparison with responders, being 68.9 and 43.4%, respectively, this did not reach a statistical significance. Conclusions PDL-1 expression did not show a discernible relationship with any patients' or disease parameters. Moreover, it did not influence patients' response to treatment or survival. Refractory cases displayed higher expression, but they were too few to draw statistical inferences, with the need of a more ample sample size. (C) 2019 The Egyptian Journal of Haematology