Rajkumar, S Vincent

Abstract Monoclonal gammopathy of undetermined significance (MGUS) is associated with a long-term risk of progression to multiple myeloma (MM) or related malignancy. To prevent serious myeloma-related complications, lifelong annual follow-up has been recommended, but its value is unknown. We reviewed all patients from southeastern Minnesota seen at Mayo Clinic between 1973 and 2004 with MGUS who subsequently progressed to MM. Of 116 patients, 69% had optimal follow-up of MGUS. Among these, abnormalities on serial follow-up laboratory testing led to the diagnosis of MM in 16%, whereas MM was diagnosed only after serious MM-related complications in 45%. In the remaining, workup of less serious symptoms (25%), incidental finding during workup of unrelated medical conditions (11%), and unknown (3%) were the mechanisms leading to MM diagnosis. High-risk MGUS patients (≥ 1.5 g/dL and/or non-IgG MGUS) were more likely to be optimally followed (81% vs 64%), and be diagnosed with MM secondary to serial follow-up testing (21% vs 7%). This retrospective study suggests that routine annual follow-up of MGUS may not be required in low-risk MGUS. Future studies are needed to replicate and expand our findings and to determine the optimal frequency of monitoring in higher-risk MGUS patients.

Abstract Obesity and black race have been associated with excess risk of multiple myeloma. The association of obesity with monoclonal gammopathy of undetermined significance (MGUS) is unknown. Further, it is not known whether the increased risk of multiple myeloma and MGUS in blacks is related to socioeconomic status, genetic susceptibility, or both. We screened 1000 black and 996 white women (range, 40-79 years) of similar socioeconomic status for MGUS; the aim of the study was to assess MGUS risk in relation to obesity and race. A total of 39 (3.9%) blacks and 21 (2.1%) whites had MGUS. On multivariate analysis, obesity (odds ratio [OR] = 1.8; P = .04), black race (OR = 1.8; P = .04), and increasing age (> 55 vs < 43 years; OR = 2.5; P = .03) were independently associated with an excess risk of MGUS. Our findings support the hypothesis that obesity is etiologically linked to myelomagenesis. The 2-fold excess of MGUS among blacks compared with whites of similar socioeconomic status supports a role for susceptibility genes in MGUS.

Purpose To assess the impact of age on outcome and to analyze the projected years of life lost in patients with multiple myeloma. Patients and Methods Ten thousand five hundred forty-nine patients were evaluated; 6,996 patients were treated with conventional chemotherapy, and 3,553 patients were treated with high-dose therapy with autologous stem-cell transplantation. Results Mean observed and relative overall survival times in the entire cohort were 3.7 and 3.9 years, respectively. Observed survival decreased steadily from 6.4 years in patients younger than age 50 years to 2.5 years in patients ≥ age 80 years. A similar decrease was noted for relative survival. Higher age correlated significantly with higher International Staging System (ISS) stage. Relative excess risk of death differed significantly between 10-year age cohorts beginning from age 40 years (P < .001 for age 50 to 59 v age 40 to 49, P < .001 for age 60 to 69 v age 50 to 59, P < .001 for age 70 to 79 v age 60 to 69, and P = .009 for age ≥ 80 v 70 to 79). The average years of life lost per patient was 16.8 years in the entire patient cohort and decreased steadily from 36.1 years in patients younger than 40 years old to 4.6 years in patients ≥ age 80 years. Conclusion Age is associated with higher ISS stage and is an important risk factor for early mortality. Survival declined continuously by each decade from age 50 to age ≥ 80 from more than 6 to less than 3 years. The average of years of life lost in patients with myeloma is higher than in many other cancers and amounts to more than 30 years in patients younger than 40 years old but decreases to less than 5 years in patients age 80 years or older.

Purpose HIV-infected persons have an elevated risk of developing non-Hodgkin's lymphoma (NHL); this risk remains increased in the era of effective HIV therapy. We evaluated serum immunoglobulin (Ig) proteins as predictors of NHL risk among HIV-infected individuals. Patients and Methods By using three cohorts of HIV-infected persons (from 1982 to 2005), we identified 66 individuals who developed NHL and 225 matched (by cohort, sex, ethnicity, age, and CD4 count), HIV-infected, lymphoma-free controls who had available stored prediagnostic blood samples. Serum/plasma samples obtained 0 to 2 years and 2 to 5 years before diagnosis/selection were assayed for IgG, IgM, and IgA levels; monoclonal (M) Igs; and κ and λ free light chain (FLC) levels. Patients and matched controls were compared by using conditional logistic regression. Results The κ and λ FLCs were both significantly higher in patients (eg, in 2- to 5-year window: median κ, 4.24 v 3.43 mg/dL; median λ, 4.04 v 3.09 mg/dL) and strongly predicted NHL in a dose-response manner up to 2 to 5 years before diagnosis/selection (eg, NHL risk 3.76-fold higher with κ concentration at least 2.00 times the upper limit of normal, and 8.13-fold higher with λ concentration at least 2.00 times the upper limit of normal compared with normal levels). In contrast, IgG, IgM, and IgA levels were similar in patients and controls. M proteins were detected in only two patients with NHL (3%) and in nine controls (4%), and they were not significantly associated with NHL risk. Conclusion Elevated FLCs may represent sensitive markers of polyclonal B-cell activation and dysfunction and could be useful for identifying HIV-infected persons at increased NHL risk.

Purpose To provide an overview on smoldering (asymptomatic) multiple myeloma (SMM) including current diagnostic criteria, predictors of progression, pattern of progression, and outcome. Design A comprehensive review of the literature on risk factors for progression, treatment attempts to delay progression and outcome in patients with SMM. Results The risk factors for progression of SMM include: plasma cell mass including M-protein size and percentage of bone marrow clonal plasma cells (BMPC), abnormal free light chain ratio, proportion of phenotypically abnormal BMPC, immunoparesis, evolution pattern (evolving v nonevolving), and pattern of magnetic resonance imaging abnormalities. Most patients with SMM progress with anemia and/or skeletal involvement. Immediate therapy with cytotoxic agents, such as melphalan/prednisone has not resulted in improved outcome. Patients should not be treated until progressive disease with end-organ damage occurs. Increasing anemia is the most reliable indicator of progression. Conclusion These recently recognized predictors of outcome may be helpful for better disease monitoring and for investigation of new treatment approaches. Thus, recommendations for follow-up every to 3 to 6 months depending on the risk of progression are suggested, and clinical trials with new noncytotoxic biologically derived agents to delay progression, particularly in high-risk patients, are ongoing.

AbstractThe objective of this case-control study was to compare the efficacy and toxicity of lenalidomide plus dexamethasone (len/dex) versus thalidomide plus dexamethasone (thal/dex) as initial therapy for newly diagnosed myeloma. We retrospectively studied 411 newly diagnosed patients treated with len/dex (228) or thal/dex (183) at the Mayo Clinic. The differences were similar in a matched-pair analysis that adjusted for age, sex, transplantation status, and dexamethasone dose. The proportions of patients achieving at least a partial response to len/dex and thal/dex were 80.3% versus 61.2%, respectively (P < .001); very good partial response rates were 34.2% and 12.0%, respectively (P < .001). Patients receiving len/dex had longer time to progression (median, 27.4 vs 17.2 months; P = .019), progression-free survival (median, 26.7 vs 17.1 months; P = .036), and overall survival (median not reached vs 57.2 months; P = .018). A similar proportion of patients in the 2 groups experienced at least one grade 3 or 4 adverse event (57.5% vs 54.6%, P = .568). Main grade 3 or 4 toxicities of len/dex were hematologic, mainly neutropenia (14.6% vs 0.6%, P < .001); the most common toxicities in thal/dex were venous thromboembolism (15.3% vs 9.2%, P = .058) and peripheral neuropathy (10.4% vs 0.9%, P < .001). Len/dex appears well-tolerated and more effective than thal/dex. Randomized trials are needed to confirm these results.

AbstractImmune-related deficiencies are well-known complications of chronic lymphocytic leukemia (CLL). Although recent data indicate that almost all CLL patients are preceded by a monoclonal B-cell lymphocytosis precursor state, patterns of immune defects preceding CLL diagnosis are unclear. We identified 109 persons who developed CLL from the prospective and nationwide Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial with 77 469 participants, with serially collected prediagnostic serum samples. We assayed monoclonal (M)–proteins, κ/λ free light chains (FLCs) in prediagnostic obtained up to 9.8 years before CLL diagnosis. The prevalence of an abnormal FLC ratio, M-protein, and hypogamma-globulinemia before CLL diagnosis was 38% (95% confidence interval, 29%-47%), 13% (7%-21%), and 3% (1%-8%), respectively. M-proteins and abnormal FLC ratios were detected up to 9.8 years before CLL diagnosis in a total of 48 persons (44%). Hypogammaglobulinemia was not present until 3 years before the diagnosis of CLL. Among 37 patients with information on tumor cell immunophenotype, an association between immunophenotype and involved FLC (P = .024, Fisher exact test) was observed. Among 61 persons with a normal FLC ratio and without an M-protein, 17 had elevated κ and/or λ FLC levels, indicating polyclonal B-cell activation in 17 of 109 (16%) patients. These findings support a role for chronic immune stimulation in CLL genesis.

Abstract Monoclonal gammopathy of undetermined significance (MGUS) is a common premalignant plasma cell proliferative disorder with a lifelong risk of progression to multiple myeloma. Because myeloma is an incurable malignancy, strategies to delay or prevent progression in high-risk patients are of considerable importance. (Clin Cancer Res 2009;15(18):5606–8)