EFFICIENCY OF BONE MARROW PRECURSOR CELL COLONY-FORMING AS A PREDICTOR OF DISEASE COURSE IN PLASMA CELL MYELOMA PATIENTS WITH A HISTORY OF RADIATION EXPOSURE

Abstract

Objective. Assessment of role of the bone marrow colony-forming efficiency in plasma cell myeloma patients at different stages of treatment as a prognostic criterion for the disease course. Materials and methods. The colony forming efficiency (CFE) was assayed in stage I–II plasma cell myeloma (PCM) patients (n = 37) aged 42–73, namely in patients survived after the Chornobyl NPP accident (n = 21) and persons not exposed to ionizing radiation (n = 16). There were 11 males exposed to ionizing radiation and having got stage I PCM, 9 males and 3 females exposed and having got stage II PCM, 3 males and 3 females not exposed and having got stage I PCM, 6 males and 2 females not exposed and having got stage II PCM. Healthy persons (n = 20) were included in the control group. Results. Number of the bone marrow (BM) granulocyte-macrophage colony-forming units (CFU-GM) in both exposed and not exposed PCM patients depended on a disease stage. CFU-GM was (16.7 ± 1.2) in the stage I PCM patients vs. (11.1 ± 1.1) in the stage II PCM ones both being lower (p < 0.05) compared to control (64.5 ± 2.2). Changes in cluster formation were similar, i.e. (37.7 ± 1.6) and (19.4 ± 1.3) correspondingly in the stage I and stage II PCM patients. Respective values in control were (89.8 ± 3.6). The CFE in stage I and stage II PCM patients at the time of diagnosis was lower (5.7 ± 1.5 and 2.4 ± 1.1 respectively) vs. control (39.5 ± 1.51, p < 0.05), but has increased in remission up to (29. 6 ± 1.8) and (13.8 ± 1.2) respectively. There was no difference at that between the irradiated and non-irradiated patients. Number of the fibroblast colony-forming units (CFU-F) in the stage I and stage II PCM patients during diagnosis, namely (43.9 ± 5.4) and (22.5 ± 3.7), was lower (p < 0.05) vs. control (110.5 ± 4.9). Upon reaching remission the CFU-F value increased significantly (p < 0.05), reaching (87.4 ± 4.2) and (55.6 ± 2.7) correspondingly in the stage I and stage II PCM patients. Conclusion. Dependence of the BM cell CFE on the stage of PCM and presence or absence of remission was established. Prognostic value of the CFE of BM CFU-GM in terms of life span of patients was shown (Ro Spearm = 0.39, p < 0.02), namely in case of CFE > 20 before the polychemotherapy administration the life span of PCM patients was significantly longer vs. cases of CFE < 20. Key words: plasma cell myeloma, bone marrow, granulocyte-macrophage colony-forming unit, fibroblast colony-forming unit, cluster.