The Comparative Analysis of Bone Marrow Lymphocyte Subsets in Children with Acute Lymphoblastic Leukemia, Rhabdomyosarcoma, and Ewing’s Sarcoma

Russian and foreign literature presents insufficient data about the bone marrow immune system of children under normal and pathological conditions (acute leukemia (AL) and solid tumors). The aim of the research was to study the quantitative characteristics of bone marrow lymphocytes subpopulations in children with developing acute leukemia and small round cell sarcomas (rhabdomyosarcoma (RMS) and Ewing’s sarcoma family tumors (ESFT). Materials and methods. The study included 111 children aged 9 months to 17 years (mean age – 7.6±0.4 years). Rhabdomyosarcoma was diagnosed in 16 children, Ewing’s sarcoma (CIO) — in 16 children, acute lymphoblastic leukemia (ALL) — in 38 children, and acute myeloid leukemia (AML) — in 26 children. Malignancy was excluded basing on complex assessment in 15 cases (experimental group). All patients underwent cytological and immunological examination of bone marrow. Results. Typical change in the bone marrow subpopulations of patients with both types of sarcomas was the increase in the percentage of CD3+HLADR+ and CD8+HLADR+ T-cells and the decrease in the percentage of Leu8+CD4+ T cells versus the control group data (p 0.05). Comparison of bone marrow lymphocytes subpopulations in ALL and AML patients demonstrated the significant differences only in the percentage of CD19+ and CD19+CD5+ B cells, the value was significantly lower in AML patients (13.4%±1.8% vs 19.5±2.1, p=0.033 and 2.2%±0.5% vs 4.7±0.8, p=0.016, respectively). The percentage of CTLs was proportionately lower under AL than sarcomas, the maximum relative content of CD8 + T cells was revealed in the bone of RMS patients. The T-helper cells content in all four treatment groups did not significantly differ in relative and absolute values (p>0.05). Conclusions. Comprehensive morphological and immunological examination results demonstrated that these cancers are characterized by specific changes in subpopulation content of T and B bone marrow lymphocytes that revealed their clinical and prognostic value, the mechanisms of interaction between the tumor and the immune system, and may be useful in the development of immunotherapy programs.