Contributions
Abstract: PB2253
Type: Publication Only
Background
Monoclonal gammopathy of undetermined significance (MGUS) is a group of diseases with the proliferation of cells of lymphoid or plasmocyte nature <10% secreting various pathological immunoglobulins in blood serum and / or urine <30 g / l with no foci of lysis, kidney damage, hypercalcemia and risk of progression of 1% in a year
Aims
to detect possible risks of progression of monoclonal gammopathy in patients of Gomel region.
Methods
The material for the study was samples of whole venous blood and bone marrow from 28 patients with pathological paraprotein who underwent examination and treatment during the period 2014-2017 in the SI "RRCRM&HE" in Gomel (Belarus). The diagnosis was confirmed by the presence of pathological immunoglobulin in the blood and / or urine and tumor immunophenotype of plasma or lymphoid cells of bone marrow. Antigen expression was determined by flow cytometry. The results were estimated at the time of determination of the pathological protein. The number of clonal plasma cells in the bone marrow was 4.6% (1.2-15%) on an average. Monoclonal gammopathy was more common in women (62.9% were female). The median age was 64 years (46-80 years).
Results
In our study pathological paroprotein was represented by IgG (50.0%), IgA (17.9%), IgM (7.1%), Bens-Jones protein (14.3%) and absence of secretion of Ig (10.7% %). Monoclonal gammapathy with the presence of IgG and Bence-Jones protein progressed to multiple myeloma during the first year of follow-up in 9 (32.1%) patients. In one patient, the disease was transformed into Waldenstrom's macroglobulinemia within three years. During this period of time, a significant increase in CD20 expression was detected proportionally to the increase in the M-protein index. Two patients from this group showed a significant increase in CD117 expression (p = 0.052) along with a high level of pathological M-protein. A high risk of progression was associated with the M-protein with IgM secretion. Excess of lactate dehydrogenase (LDH) indices was also significant (p = 0.05) in patients with a high risk of progression, changes in B2-microglobulin (possibly due to a small percentage of plasma cells in the bone marrow) were not detected.
Conclusion
Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant proliferation of B-lymphocytes with a high risk of progression to multiple myeloma, Waldenstrom's macroglobulinemia. Despite a very short observation period, during our study we detected a significant increase in CD117 and CD20 expression in patients who progressed to multiple myeloma and Waldenstrom’s macroglobulinemia, which may be an unfavorable prognostic factor. Perhaps this will help to identify patients at high risk for progression initially, which is important in determining the time of the start of specific therapy.
Session topic: 14. Myeloma and other monoclonal gammopathies - Clinical
Keyword(s): MGUS, Multiple Myeloma, Waldenstrom's macroglobulinemia
Abstract: PB2253
Type: Publication Only
Background
Monoclonal gammopathy of undetermined significance (MGUS) is a group of diseases with the proliferation of cells of lymphoid or plasmocyte nature <10% secreting various pathological immunoglobulins in blood serum and / or urine <30 g / l with no foci of lysis, kidney damage, hypercalcemia and risk of progression of 1% in a year
Aims
to detect possible risks of progression of monoclonal gammopathy in patients of Gomel region.
Methods
The material for the study was samples of whole venous blood and bone marrow from 28 patients with pathological paraprotein who underwent examination and treatment during the period 2014-2017 in the SI "RRCRM&HE" in Gomel (Belarus). The diagnosis was confirmed by the presence of pathological immunoglobulin in the blood and / or urine and tumor immunophenotype of plasma or lymphoid cells of bone marrow. Antigen expression was determined by flow cytometry. The results were estimated at the time of determination of the pathological protein. The number of clonal plasma cells in the bone marrow was 4.6% (1.2-15%) on an average. Monoclonal gammopathy was more common in women (62.9% were female). The median age was 64 years (46-80 years).
Results
In our study pathological paroprotein was represented by IgG (50.0%), IgA (17.9%), IgM (7.1%), Bens-Jones protein (14.3%) and absence of secretion of Ig (10.7% %). Monoclonal gammapathy with the presence of IgG and Bence-Jones protein progressed to multiple myeloma during the first year of follow-up in 9 (32.1%) patients. In one patient, the disease was transformed into Waldenstrom's macroglobulinemia within three years. During this period of time, a significant increase in CD20 expression was detected proportionally to the increase in the M-protein index. Two patients from this group showed a significant increase in CD117 expression (p = 0.052) along with a high level of pathological M-protein. A high risk of progression was associated with the M-protein with IgM secretion. Excess of lactate dehydrogenase (LDH) indices was also significant (p = 0.05) in patients with a high risk of progression, changes in B2-microglobulin (possibly due to a small percentage of plasma cells in the bone marrow) were not detected.
Conclusion
Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant proliferation of B-lymphocytes with a high risk of progression to multiple myeloma, Waldenstrom's macroglobulinemia. Despite a very short observation period, during our study we detected a significant increase in CD117 and CD20 expression in patients who progressed to multiple myeloma and Waldenstrom’s macroglobulinemia, which may be an unfavorable prognostic factor. Perhaps this will help to identify patients at high risk for progression initially, which is important in determining the time of the start of specific therapy.
Session topic: 14. Myeloma and other monoclonal gammopathies - Clinical
Keyword(s): MGUS, Multiple Myeloma, Waldenstrom's macroglobulinemia