Kyle, Robert A.

Abstract Allogeneic hematopoietic cell transplantation in multiple myeloma is limited by prior reports of high treatment-related mortality. We analyzed outcomes after allogeneic hematopoietic cell transplantation for multiple myeloma in 1207 recipients in 3 cohorts based on the year of transplantation: 1989-1994 (n = 343), 1995-2000 (n = 376), and 2001-2005 (n = 488). The most recent cohort was significantly older (53% > 50 years) and had more recipients after prior autotransplantation. Use of unrelated donors, reduced-intensity conditioning and the blood cell grafts increased over time. Rates of acute graft-versus-host (GVHD) were similar, but chronic GVHD rates were highest in the most recent cohort. Overall survival (OS) at 1-year increased over time, reflecting a decrease in treatment-related mortality, but 5-year relapse rates increased from 39% (95% confidence interval [CI], 33%-44%) in 1989-1994 to 58% (95% CI, 51%-64%; P < .001) in the 2001-2005 cohort. Projected 5-year progression-free survival and OS are 14% (95% CI, 9%-20%) and 29% (95% CI, 23%-35%), respectively, in the latest cohort. Increasing age, longer interval from diagnosis to transplantation, and unrelated donor grafts adversely affected OS in multivariate analysis. Survival at 5 years for subjects with none, 1, 2, or 3 of these risk factors were 41% (range, 36%-47%), 32% (range, 27%-37%), 25% (range, 19%-31%), and 3% (range, 0%-11%), respectively (P < .0001).

Abstract Since monoclonal gammopathy of undetermined significance (MGUS) was first described more than 30 years ago, the definition of the entity has evolved. Today, 3 distinct clinical MGUS subtypes have been defined: non–immunoglobulin M (IgM; IgG or IgA) MGUS, IgM MGUS, and light chain MGUS. Each clinical MGUS subtype is characterized by unique intermediate stages and progression events. Although we now have strong evidence that multiple myeloma is consistently preceded by a precursor state at the molecular level, there is urgent need to better understand mechanisms that regulate transformation from precursor to full-blown multiple myeloma. In the future, if such knowledge was available, it would allow clinicians to define high-risk and low-risk precursor patients for a more tailored clinical management. Also, it would provide insights on the individual patient's disease biology, which, in turn, can be used for targeted and more individualized treatment strategies. On the basis of current clinical guidelines, patients diagnosed with MGUS and smoldering myeloma should not be treated outside of clinical trials. In the near future, it seems reasonable to believe that high-risk precursor patients will likely become candidates for early treatment strategies. In this review, we discuss novel insights from recent studies and propose future directions of relevance for clinical management and research studies. Clin Cancer Res; 17(6); 1243–52. ©2011 AACR.

AbstractA panel of members of the 2009 International Myeloma Workshop developed guidelines for risk stratification in multiple myeloma. The purpose of risk stratification is not to decide time of therapy but to prognosticate. There is general consensus that risk stratification is applicable to newly diagnosed patients; however, some genetic abnormalities characteristic of poor outcome at diagnosis may suggest poor outcome if only detected at the time of relapse. Thus, in good-risk patients, it is necessary to evaluate for high-risk features at relapse. Although detection of any cytogenetic abnormality is considered to suggest higher-risk disease, the specific abnormalities considered as poor risk are cytogenetically detected chromosomal 13 or 13q deletion, t(4;14) and del17p, and detection by fluorescence in situ hybridization of t(4;14), t(14;16), and del17p. Detection of 13q deletion by fluorescence in situ hybridization only, in absence of other abnormalities, is not considered a high-risk feature. High serum β2-microglobulin level and International Staging System stages II and III, incorporating high β2-microglobulin and low albumin, are considered to predict higher risk disease. There was a consensus that the high-risk features will change in the future, with introduction of other new agents or possibly new combinations.

AbstractA panel of members of the 2009 International Myeloma Workshop developed guidelines for standard investigative workup of patients with suspected multiple myeloma. Both serum and urine should be assessed for monoclonal protein. Measurement of monoclonal protein both by densitometer tracing and/by nephelometric quantitation is recommended, and immunofixation is required for confirmation. The serum-free light chain assay is recommended in all newly diagnosed patients with plasma cell dyscrasias. Bone marrow aspiration and/or biopsy along with demonstration of clonality of plasma cells are necessary. Serum β2-microglobulin, albumin, and lactate dehydrogenase are necessary for prognostic purposes. Standard metaphase cytogenetics and fluorescent in situ hybridization for 17p, t(4;14), and t(14;16) are recommended. The skeletal survey remains the standard method for imaging screening, but magnetic resonance imaging frequently provides valuable diagnostic and prognostic information. Most of these tests are repeated during follow-up or at relapse.

Abstract It is essential that there be consistency in the conduct, analysis, and reporting of clinical trial results in myeloma. The goal of the International Myeloma Workshop Consensus Panel 1 was to develop a set of guidelines for the uniform reporting of clinical trial results in myeloma. This paper provides a summary of the current response criteria in myeloma, detailed definitions for patient populations, lines of therapy, and specific endpoints. We propose that future clinical trials in myeloma follow the guidelines for reporting results proposed in this manuscript.

Abstract Immunoglobulin free light chains (FLCs) are the precursors of amyloid fibrils in primary amyloidosis (AL). We studied the relationship between FLC levels and clinical features in 730 patients with newly diagnosed AL. The plasma cell clone was λ in 72% patients, and κ in 28% patients. κ-AL had more GI tract and liver involvement, where as renal involvement was more with λ-AL. While the overall survival (OS) was similar for κ and λ-AL, the median OS for those without an identifiable serum heavy chain was significantly shorter (12.6 vs 29.9 months; P = .02). The OS was shorter among those with a higher dFLC (involved FLC−uninvolved FLC; κ > 29.4 mg/dL or λ > 18.2 mg/dL using median for cutoff); 10.9 vs 37.1 months; P < .001. In multivariate analysis, dFLC was independent of other prognostic factors. The type of light chain impacts the spectrum of organ involvement and the FLC burden correlates with survival in AL.

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.