IMMUNOLOGICAL ASPECTS OF BONE MARROW INVOLVEMENT IN FOLLICULAR LYMPHOMA

Introduction. Bone marrow is one of the most common sites of involvement in follicular lymphoma (70 % of cases). Comparison of bone marrow lymphocyte subpopulations with the immunophenotype of primari tumor ant its microinvirement has not been done. Matherials and methods. Study has been done in 78 patients with follicular lymphoma. Diagnosis in each case was verified according to criteria of WHO classification (2008). Objective - to compare subpopulation composition of lymphocytes in bone marrow of patients with follicular lymphoma with immunophenotype of the primary tumor and the characteristics of the non-tumor microenvironment. Results. Histological detection of bone marrow involvement was associated with significant elevation of mature B-cells (CD19+, CD20+) as well as CD10+ lymphovytes in bone marrow aspiration biopsy specimens. In CD10-negative follicular lymphoma T-cell content (CD5+CD19-) was higher than in CD10+ cases (32.2 ± 7.6 % и 13.5 ± 3.4 %; р = 0.021). Oppositively, number of B-cells in bone marrow (CD19+CD5-, CD10+) was higher in CD10+ cases (p < 0.05). Intensive infiltration of primary tumor with T-cells was associated with lower number of bone marrow B-cells with specific follicular lymphoma phenotype - CD10+, CD19+CD23+ - (р = 0.001 and 0.048, correspondingly). Elevation of bone marrow lymphocytes was associated with higher number of mature T-cells in bone marrow - CD3, CD5, CD7, CD4, CD8. Number of B-cells (CD20+, CD22+) and (CD19+, CD19+CD5-), as well as B-cells expressing HLA-DR, CD23, CD10, CD38 was either equal or even higher in group of patients without lymphocytosis in bone marrow. In the gruop of normal level of oxyphilic normoblasts in bone marrow higher level of mature bone marrow B-cells (CD19, CD20, CD22) was noted. Conclusion. Our data confirm that verification of bone marrow involvement in follicular lymphoma should be immunological. T-cell microinvirement in primary tumor prevents of follicular lymphoma dissemination to bone marrow. Subpopulations of bone marrow lymphocytes are related to the immunophenotype of primary tumor (CD10). Bone marrow microenvironment (CD8+ lymphocytes) correlates with the absense of specific bone marrow involvement according to histology of bone marrow trephine biopsy.

фолликулярная лимфома, костный мозг, субпопуляция лимфоцитов, follicular lymphoma, bone marrow, subpopulation of lymphocytes

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