Familial monoclonal gammopathy: hyper-responsive B cells in unaffected family members

Background: In Iceland, eight families have been identified with multiple cases of monoclonal gammopathies (MG) and other lymphoproliferative diseases. In one of these families with several cases of monoclonal gammopathy of undetermined significance (MGUS) and Waldenströms macroglobulinemia, in vitro stimulation with poke‐weed mitogen revealed hyper‐responsive B cells showing increased immunoglobulin production in one‐third of disease‐free family members. Design and methods: In this study, the families were further traced and the list of names produced was compared with The Icelandic Cancer Registry (ICR) to find all recent cases of lymphoproliferative diseases. First‐degree relatives and descendants older than 20 yrs of age (n = 350) were selected for screening for paraprotein. Selected family members were tested for B‐cell hyper‐responsiveness and the lymphocyte phenotype was analysed by flow cytometry. Results: Comparison of the total list of 4370 family members with the ICR revealed 22 new cases and screening for serum paraprotein identified nine new cases of MG, eight being first‐degree relatives of known probands. Sixty cases of lymphoproliferative diseases are currently known within the eight families, five of them containing both IgG/A and IgM disorders. Twelve hyper‐responders (HR) were identified in four families, eight from one family, of whom four were known already. Stimulated B cells from HR had a significantly higher proportion of CD27⁺ memory/plasma cells than controls. Conclusion: Identification of new affected family members by screening confirms a hereditary predisposition to B‐cell proliferative diseases. Contrary to most studies, IgG/A and IgM disorders occurred together in five families. In four families, enhanced B‐cell responsiveness was found in healthy subjects clustered around cases.     

Abnormalities in lymphocyte profile and specificity repertoire of patients with Waldenstrom's macroglobulinemia, multiple myeloma, and IgM monoclonal gammopathy of undetermined significance

The characteristics of T and B lymphocyte profile and B lymphocyte specificity repertoire were compared in patients with Waldenstrom's macroglobulinemia (WM), IgM monoclonal gammopathy of undetermined significance (IgM MGUS), multiple myeloma (MM), and age-matched normal subjects. Patients with MM had both significantly reduced frequency and number of sIg+ (surface Ig) B cells, whereas patients with WM and IgM MGUS had a reduced frequency but normal numbers of sIg+ B cells in circulation as detected in a capping assay. WM was distinguished by the large numbers of cells in the peripheral blood lymphocyte (PBL) pool that expressed CD9 (BA-2) and CD24 (BA-1) and were monoclonal, based on light chain analysis using flow cytometry. The profile of T lineage cells showed that the ratio of CD4:CD8 was significantly reduced in both MM and WM due to a reduction in the CD4 set. The CD4+ cells were qualitatively abnormal as well, with an enriched proportion of the 4B4+ (CDw29) subset and decreased proportion of the Lp220+ (CD45R) subset. This appeared to be an effect of the disease process on the relatively immature Lp220+ set. From clonal analysis, those patients with WM or IgM MGUS (unlike MM patients) did not exhibit enhanced reactivity with auto-Ig determinants, and most WM patients (7/8) and half of the IgM MGUS patients (3/6) did not have enriched proportions of B cells reactive to tetanus toxoid (TT). The TT-specific B cells in both WM and IgM MGUS, in contrast to MM, appeared fully functional in secretion of anti-TT IgM in vivo. We speculate that the more severe immunodeficiency in MM may be controlled or exacerbated by the presence of an anti-Ig network. The absence of this network in WM allows a relatively more effective immune response, but the immunodeficiency that is observed in these patients involves some abnormality in normal lymphocyte differentiation (is also present in MM).     

Differences in the distribution of cytogenetic subtypes between multiple myeloma patients with and without a family history of monoclonal gammopathy and multiple myeloma

We previously reported an increased risk of monoclonal gammopathy of undetermined significance (MGUS) in first‐degree relatives of MGUS and multiple myeloma patients. Here, we examine whether primary cytogenetic categories of myeloma differ between patients with and without a family history of MGUS or myeloma. We studied 201 myeloma patients with available data on family history and molecular cytogenetic classification. Myeloma with trisomies was more common in probands who had an affected first‐degree relative with MGUS or myeloma compared with those without a family history (46.9% vs. 33.5%, P = 0.125); however, the difference was not statistically significant. Additional studies on the cytogenetic types of myeloma associated with familial tendency are needed.     

Peripheral blood lymphocyte subsets in multiple myeloma and monoclonal gammopathy of undetermined significance

Summary. Peripheral blood lymphocyte subsets were analysed by flow cytometry and compared among 43 patients with untreated multiple myeloma (MM), 16 patients with monoclonal gammopathy of undetermined significance (MGUS) and 26 controls. The age and sex distributions of the patients and controls were comparable, which is important, since in the controls there was a significant effect of age and/or sex on the number of CD3⁺, CD57⁺, CD8⁺57⁺, CD16⁺ and CD3^-56⁺ lymphocyte subsets, and on the CD4⁺/CD8⁺ and CD4⁺Leu–8⁺/CD4⁺ ratios. In MM, the number of CD8⁺ and CD57⁺ cells and the CD4⁺/CD8⁺ ratio were related to the clinical stage. The number of CD20⁺, CD3⁺, CD4⁺, CD16⁺ and CD3^-56⁺ cells and the CD3⁺/CD20⁺ ratio were significantly different in MM patients compared to age- and sex-matched controls as was the number of CD3¹ and CD4¹ cells of MGUS patients compared to controls. Further, there were significant differences in the CD3^-/CD20⁺ ratio between MM and MGUS patients and between stage I MM and MGUS. The role of peripheral blood lymphocyte subsets in differentiating monoclonal gammopathies merits further study.     

Interleukin-6 is expressed by plasma cells from patients with multiple myeloma and monoclonal gammopathy of undetermined significance

Interleukin-6 (IL-6) is an important growth factor for human myeloma cells in vitro and in vivo . However, the identity of the cells producing IL-6 in vivo in patients with multiple myeloma (MM) remains the subject of debate. We have developed a sensitive dual-colour fluorescence in situ hybridization (FISH) technique to investigate the expression of IL-6 mRNA by individual bone marrow plasma cells from patients with multiple myeloma, monoclonal gammopathy of undetermined significance (MGUS) and healthy subjects. IL-6 mRNA could be identified in all immunoglobulin light chain (IgLC) expressing cells from all patients with MM and MGUS. The IL-6 protein could also be detected by direct immunofluorescence in all plasma cells (cytoplasmic light chain positive) from all patients with MM and MGUS. Furthermore, it was also possible to demonstrate cytoplasmic IL-6 staining of plasma cells from patients with MM by flow cytometric analysis. In contrast, neither the IL-6 mRNA or protein could be detected in normal plasma cells from healthy bone marrow donors. These data demonstrate that plasma cells from patients with MM and MGUS express the IL-6 mRNA and synthesize the IL-6 protein and support the hypothesis that autocrine synthesis of IL-6 is of importance in patients with MM.     

Incidental finding of monoclonal gammopathy in blood donors: a follow-up study

Background.The incidental finding of monoclonal immunoglobulin in the sera of healthy blood donors is a relatively frequent event and in such cases the subjects are commonly deferred permanently from donating blood. However, no follow-up studies of these cases have been published so far.Results.Out of 8,197 regular blood donors, monoclonal gammopathy was detected in 104 subjects (1.3%). The median age at detection was 53 years, the median monoclonal protein concentration was 0.2 g/dL and the cumulative follow-up of these cases amounted to 763 person/years. In two cases asymptomatic multiple myeloma was diagnosed within 6 months of detection of the gammopathy and in 14 cases, the monoclonal gammopathy was transient. The remaining 88 cases were classified as having monoclonal gammopathy of undetermined significance (MGUS). Out of these, two events related to monoclonal gammopathy were observed during the follow up: one lymphoma and one light chain deposition nephropathy.Discussion.According to current prognostic staging systems, the majority of blood donors with monoclonal gammopathy were classified as having low-risk MGUS and had a very low incidence of lymphoproliferative diseases. Permanent deferral of blood donors with stable MGUS causes about a 1% loss of potential blood donations and it represents a “precautionary measure” that needs to be substantiated and validated.     

Monoclonal gammopathy of undetermined significance and smouldering multiple myeloma: emphasis on risk factors for progression

Monoclonal gammopathy of undetermined significance (MGUS) is characterized by a serum monoclonal protein <30 g/l, <10% plasma cells in the bone marrow, and absence of end-organ damage (CRAB-hypercalcaemia, renal insufficiency, anaemia, or bone lesions). MGUS is present in 3% of persons >50 years and in 5% >70 years of age. The risk of progression to multiple myeloma (MM) or a related disorder is 1% per year. Patients with risk factors consisting of an abnormal serum free light chain ratio, non-immunoglobulin G (IgG) MGUS, and an elevated serum M protein >/=15 g/l had a risk of progression at 20 years of 58%, compared with 37% with two risk factors present, 21% with one risk factor present, and 5% when none of the risk factors were present. Smouldering (asymptomatic) multiple myeloma is characterized by having a serum IgG or IgA monoclonal protein of 30 g/l or higher and/or 10% or more plasma cells in the bone marrow but no evidence of end-organ damage. The cumulative probability of progression to active MM or amyloidosis was 51% at 5 years, 66% at 10 years and 73% at 15 years; the median time to progression was 4.8 years.     

Immunophenotypic aberrations, DNA content, and cell cycle analysis of plasma cells in patients with myeloma and monoclonal gammopathies

We describe the immunophenotypic and gross DNA defects in 55 patients with myeloma and 50 patients with monoclonal gammopathy and review the literature on this subject (MedLine, 1994-2000). Our data confirmed previous reports indicating that in myeloma nearly all marrow plasma cells are abnormal (98.7 +/- 8.1%). In monoclonal gammopathy the fraction of abnormal plasma cells was 35.0 +/- 32.8%. In both myeloma and monoclonal gammopathy, the most frequent aberrant phenotypic features consisted of absence of expression of CD19, strong expression of CD56, and decreased intensity of expression of CD38; aberrant expression of CD10, CD20, CD22, or CD28 was observed in less than one-third of myeloma cases. The vast majority of cases had two or more phenotypic aberrations. In the DNA studies, 7% of myeloma cases were biclonal and 93% of cases were monoclonal. In those studies with only one plasma cell mitotic cycle, 37% had normal DNA content and 63% were aneuploid (hyperploid, 61%; hypoploid, 2%). The mean percentages of plasma cells in S- and G2M phases were 4.9 +/- 8.5 and 4.4 +/- 6.9%, respectively. Thirty-eight percent of cases had more than 3% of plasma cells in S phase. In monoclonal gammopathy, the DNA index of abnormal plasma cells ranged from 0.89 to 1.30 and the percentage of diploid (31%) and aneuploid (69%) cases was not different from the results found in myeloma. The differences in percentage of abnormal plasma cells in S- (7.4 +/- 8.6%) and G2M-phases (2.4 +/- 1.7%) in patients with monoclonal gammopathy were not statistically significant.     

Waldenström macroglobulinemia terminating in acute leukemia: A report of three cases

Acute leukemia was observed to develop in three patients with Waldenst?m macroglobulinemia. Each patient had been treated with cytotoxic drug therapy. Pancytopenia preceded the onset of the terminal leukemia in two of the three cases. The acute leukemias were all of acute myelogenous type. All of the patients died soon after the development of the terminal leukemia. A number of recent reports have documented acute terminal leukemia in patients with macroglobulinemias and multiple myeloma, as well as other malignant and nonmalignant diseases. The role of the cytotoxic drugs, especially chlorambucil, cyclophosphamide, and melphalan, in leukemogenesis has been raised by these recent reports.     

Upregulation of Dicer is more frequent in monoclonal gammopathies of undetermined significance than in multiple myeloma patients and is associated with longer survival in symptomatic myeloma patients

Dicer and Drosha are key enzymes in the miRNA-processing pathway which is altered in many human cancers. We analyzed Dicer and Drosha expression levels by quantitative PCR in 151 patients with monoclonal gammopathies: 102 symptomatic myeloma patients, 23 smoldering myelomas and 26 monoclonal gammopathy of undetermined significance. We found that Dicer expression values were significantly higher in monoclonal gammopathy of undetermined significance than in smoldering myelomas and symptomatic myeloma (mean ± SD, 0.84 ± 0.36 vs. 0.60 ± 0.23 and 0.62 ± 0.51; P<0.01). Moreover, the median progression-free survival was significantly longer in symptomatic myeloma patients with high expression of Dicer (not reached vs. 23.6 months; P=0.02). By contrast, no differences in the expression of Drosha among these groups of patients were observed. Our data suggest that Dicer expression may play an important role in the progression and prognosis of monoclonal gammopathies.     

High frequencies of chromosomal aberrations in multiple myeloma and monoclonal gammopathy of undetermined significance in direct chromosome preparation

Although many cases of multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) are cytogenetically normal, interphase fluorescence in situ hybridization (FISH) analyses reveal aberrations in the majority of the cases. Most likely, non-neoplastic cells are more prone to divide in culture than neoplastic cells. Direct chromosome preparations (DCP) would be one way to circumvent this methodological problem. We have investigated 47 bone marrow samples from 39 patients by DCP. A median of 58 metaphases (range 9-158) was analysed per sample. Interphase FISH analyses using probes to detect IGH rearrangements, -13/13q-, +3, +7, and +11 were also performed. Abnormal karyotypes were detected in 15 (63%) of 24 MM and in 4 (50%) of eight MGUS/smouldering MM (SMM) cases that could be successfully cytogenetically analysed. Age, sex, or degree of bone marrow plasma cell (PC) infiltration did not influence the karyotypic patterns (P > 0.05). However, the frequencies of aberrant karyotypes varied in relation to the Colcemide concentrations used - 7% (30 ng/ml) versus 69% and 67% (100 and 200 ng/ml, respectively) (P = 0.01). Combining the G-banding and FISH results, abnormalities were detected in 29 of 31 (94%) MM and in six of eight (75%) MGUS/SMM patients. Thus, cytogenetic and FISH analyses after DCP using 100-200 ng Colcemide/ml identified aberrations in most MM/MGUS/SMM, irrespective of PC percentages.     

Interleukin 6 and tumour necrosis factor alpha serum levels in monoclonal gammopathy of undetermined significance

The objectives of the present study were to compare the interleukin 6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) serum levels of individuals with monoclonal gammopathy of undetermined significance (MGUS) with those of healthy controls, and to ascertain the predictor value of these cytokines in the evolution from MGUS to multiple myeloma. After a median follow-up of 7 years from the initial cytokine measurements, nine patients with MGUS have evolved to a malignant condition. The actuarial probability of malignant transformation in patients with increased IL-6 and TNF-alpha was not significantly higher than in those with normal values.     

Criteria for the classification of monoclonal gammopathies,multiple myeloma and related disorders: a report of the International Myeloma Working Group

Summary. The monoclonal gammopathies are a group of disorders associated with monoclonal proliferation of plasma cells. The characterization of specific entities is an area of difficulty in clinical practice. The International Myeloma Working Group has reviewed the criteria for diagnosis and classification with the aim of producing simple, easily used definitions based on routinely available investigations. In monoclonal gammopathy of undetermined significance (MGUS) or monoclonal gammopathy, unattributed/unassociated (MG[u]), the monoclonal protein is < 30 g/l and the bone marrow clonal cells < 10% with no evidence of multiple myeloma, other B-cell proliferative disorders or amyloidosis. In asymptomatic (smouldering) myeloma the M-protein is ≥ 30 g/l and/or bone marrow clonal cells ≥ 10% but no r elated o rgan or t issue i mpairment (ROTI)(end-organ damage), which is typically manifested by increased c alcium, r enal insufficiency, a naemia, or b one lesions (CRAB) attributed to the plasma cell proliferative process. Symptomatic myeloma requires evidence of ROTI. Non-secretory myeloma is characterized by the absence of an M-protein in the serum and urine, bone marrow plasmacytosis and ROTI. Solitary plasmacytoma of bone, extramedullary plasmacytoma and multiple solitary plasmacytomas (± recurrent) are also defined as distinct entities. The use of these criteria will facilitate comparison of therapeutic trial data. Evaluation of currently available prognostic factors may allow better definition of prognosis in multiple myeloma.     

Serum interleukin-6 has no discriminatory role in paraproteinaemia nor a prognostic role in multiple myeloma.

We determined interleukin-6 (IL-6) levels in the serum of 212 well-defined patients with newly diagnosed paraproteinaemia and evaluated its discriminatory value and prognostic role in multiple myeloma (MM). Results were compared with serum neural cell adhesion molecule and beta-2-microglobulin, both established prognostic MM markers. Paraproteinaemia-related diagnoses were: MM (60), other haematological diseases (46), solid tumours (35), autoimmune diseases (17) and monoclonal gammopathy of unknown significance (MGUS) (54). The range of IL-6 levels in all diagnostic groups overlapped widely and did not serve as a discriminatory marker in newly diagnosed paraproteinaemia even when patients with infection or fever (42) were excluded. In MM high IL-6 levels (>/= 50 pg/ml) were not associated with a shorter survival (P = 0.24). We compared our results with 20 published studies on serum IL-6 in paraproteinaemia and/or MM. IL-6 data have to be related to the assay used (bio- or immunoassay) and to the status of MM (newly diagnosed, during therapy, progressive disease). We conclude that serum IL-6 is not specific for paraproteinaemia-related diseases and will not serve as a reliable discriminatory or prognostic marker in paraproteinaemia and MM.     

Complete response in myeloma extends survival without, but not with history of prior monoclonal gammopathy of undetermined significance or smouldering disease

Complete response (CR) is still considered an important surrogate marker for outcome in multiple myeloma (MM). Long-term survival after transplantation, however, has been observed in a substantial proportion of patients who never achieved CR. The tandem transplant trial, Total Therapy 2, enrolled 668 patients, who were randomised up-front to thalidomide (THAL) or no THAL; 56 patients were identified as having had, for at least 6 months prior to initiation of therapy, monoclonal gammopathy of undetermined significance (MGUS, n = 21), smouldering MM (SMM, n = 22) or solitary plasmacytoma of bone (SPC, n = 13). The clinical characteristics and outcomes of patients with such 'evolved' MM (E-MM) and of those with 'unknown' prior history (U-MM) were compared. Fewer patients with MGUS/SMM-E-MM had anaemia or renal failure; CR was lower (22% vs. 48%) but 4-year estimates of event-free survival (54% vs. 56% with U-MM) and overall survival (65% vs. 70% with U-MM) were similar to those with SPC-E-MM or U-MM. In the latter group, achieving CR was associated with prolonged survival. In comparison with U-MM, E-MM evolved from MGUS/SMM was associated with lower CR rate without adversely affecting survival. In contrast, CR was an independent favourable feature for survival in U-MM.     

Expression of shared idiotypes by paraproteins from patients with monoclonal gammopathy of undetermined significance

We have previously demonstrated the expression of shared idiotypes by the paraproteins from approximately one-quarter of patients with multiple myeloma (MM). We have now investigated whether similar cross-reactivity is expressed in the paraproteins of patients with monoclonal gammopathy of undetermined significance (MGUS), using a panel of 32 monoclonal antibodies (MAB) generated against follicular B cell lymphomas. The paraproteins from 76/409 (19%) patients with MGUS reacted with at least one of 23 different anti-idiotypic antibodies used in this study. 18 MABs demonstrated reactivity with more than one patient's paraprotein. Moreover, 10 MABs reacted frequently (with 5–22 paraproteins). Over half (41/76) of the reactive patients' paraproteins reacted with more than one MAB from this panel. This frequency of anti-idiotypic reactivity was similar to that of previously studied patients with myeloma, chronic lymphocytic leukaemia (CLL), and follicular B-cell lymphomas. There was no correlation between specific anti-idiotypic reactivity and the propensity to develop serious disease (MM, macroglobulinaemia, amyloidosis, or other lymphoproliferative disorders) in patients with MGUS. These results suggest that MGUS is derived from cells producing antibodies that are similar to those of other B-cell malignancies and that the pattern of idiotype expression is irrelevant to malignant potential.     

Parental longevity and survival among patients with multiple myeloma and monoclonal gammopathy of undetermined significance: a population-based study

Parental longevity is associated with an increased life expectancy; results with regard to specific diseases are conflicting. There are limited data focusing on host characteristics and their effect on survival among multiple myeloma (MM) patients and individuals with monoclonal gammopathy of undetermined significance (MGUS). Therefore, our aim was to evaluate the impact of parental longevity on survival of patients with MM and MGUS. A total of 4675 patients with MM, 6812 MGUS patients and 13 398 population-based controls for MM as well as 19 110 controls for MGUS, from 1988 to 2013, were included in the study. Longevity was defined as >90 years of age. Among MM patients, parental longevity was associated with a decreased risk of death [hazard ratio (HR) = 0·92, 95% confidence interval (CI) 0·84–0·99] and the same was true for MGUS patients (HR = 0·87, 95% CI 0·78–0·96). Having one long lived parent significantly decreased the risk of death in both groups, but was not statistically significant when both parents exceeded 90 years of age. In conclusion, parental longevity decreases the risk of death for patients with MM and MGUS which may reflect the importance of the host's genetic and environmental factors in relation to survival.     

Intravascular haemolysis and increased prevalence of myeloma and monoclonal gammopathy in congenital dyserythropoietic anaemia,type III

Abstract: A family with congenital dyserythropoietic anaemia type III was studied. Twenty patients and 10 of their healthy siblings were clinically examined and questioned about their medical history. Blood sampling and bone marrow aspirations were also performed. Forty-five percent of the patients reported symptoms of anaemia and 35% regularly felt weakness, fatigue, or headache. However, the majority of the patients regarded themselves as healthy. The bone marrow showed a uniform picture of erythroid hyperplasia with multinuclear erythroblasts and gigantoblasts with up to 12 nuclei. There was laboratory evidence of intravascular haemolysis and mild anaemia. We also observed a high prevalence of monoclonal gammopathy of undetermined significance (3 cases) and myeloma (1 case) among the patients.