Malignant transformation and life expectancy in monoclonal gammopathy of undetermined significance

Abstract

The actuarial probability of malignant transformation and the impact on expected survival were analysed in a series of 128 persons diagnosed with monoclonal gammopathy of undetermined significance (MGUS) over a 20-year period. At a median follow-up of 56 months the M-component remains stable in 101 patients (78.9%), 14 patients (10.9%) have died from non-related disorders and 13 (10.2%) have developed malignant transformation of MGUS (multiple myeloma, 10; primary amyloidosis, two; Waldenström's macroglobulinaemia, one). The actuarial probability of malignant transformation at 5 and 10 years was 8.5% and 19.2%, respectively. When different presenting features were analysed for predictive value of the malignant transformation, the IgA type of MGUS was the only variable associated with a higher probability of such an event (P less than 0.025). Although no significant difference was observed between the survival probability of persons with MGUS and that of the control population, the development of malignant transformation was associated with a shorter survival (P less than 0.001).

Monoclonal gammopathy of undetermined significance in atomic bomb survivors: incidence and transformation to multiple myeloma

“…As for the transformation from MGUS to MM, a quarter of MGUS patients developed lymphoid malignancies, 66% of which were MM, within 20-35 years of onset (Gregersen et al, 2001;Kyle et al, 2002). In our study, no lymphoid neoplasms other than MM developed among MGUS patients, although other studies have reported a variety of lymphoid malignancies besides MM, including IgM lymphoma, macroglobulinaemia and chronic lymphocytic leukaemia (Kanoh et al, 1990;Blade et al, 1992;van de Poel et al, 1995;Lolin et al, 1996;Ong et al, 1997;Vuckovic et al, 1997;Colls, 1999;Gregersen et al, 2001;Kyle et al, 2002;Ogmundsdottir et al, 2002). The transformation rate in the present study, 21% at 16 years, is quite similar to that of others, for example 12% at 10 years and 25% at 20 years (Kyle et al, 2002), 8AE5% at 5 years and 19AE2% at 10 years (Blade et al, 1992), and 11% at 14 years (van de Poel et al, 1995).…”

“…Within 20-35 years of onset, a quarter of MGUS patients develop lymphoid malignancies such as MM, immunoglobulin (Ig)M lymphoma, primary amyloidosis, macroglobulinaemia and chronic lymphocytic leukaemia (Kyle et al, 2002). The transformation of MGUS to B-cell malignancies has been studied in many countries, including the USA (Kyle et al, 2002), Iceland (Ogmundsdottir et al, 2002, the Netherlands (van de Poel et al, 1995;Ong et al, 1997), Denmark (Gregersen et al, 2001), Spain (Blade et al, 1992), Hong Kong (Lolin et al, 1996), Croatia (Vuckovic et al, 1997), New Zealand (Colls, 1999) and Japan (Kanoh et al, 1990). Here we report on the epidemiology of MGUS and its transformation to MM in the A-bomb survivor study population.…”

Immunophenotypic Aberrations, DNA Content, and Cell Cycle Analysis of Plasma Cells in Patients with Myeloma and Monoclonal Gammopathies

“…Other variables, including ␤2-microglobulin, reactive C protein, interleukin 6 (IL 6), IL 6 receptor and aminopterine were described more recently (25)(26)(27)(28)(29)(30)(31)(32). Plasma cell labeling-index (LI) and Ki-67 proliferation index were also described as variables useful in discriminating between myeloma and MG and to distinguish myeloma cases with poor prognosis from stable myeloma patients requiring no immediate therapy (33)(34)(35)(36)(37)(38)(39)(40)(41). Difficulties in implementing these assays for the clinical laboratory have limited their usefulness.…”

Pathogenesis and progression of monoclonal gammopathy of undetermined significance

“…7,31,53-58 Table 3 shows that, on average, the probability of malignant transformation at 10 years ranges from 12 to 17% and from 25 to 34% at 20 years. 7,31,54,56,57 However, the actuarial probability is clinically relevant only if patients do not die from other causes before the malignant transformation occurs. This is particularly important in conditions presenting at an advanced age, such as MGUS.…”